test(ai-chat): simplify msg factory and lock signature↔render coupling

Address non-blocking review items on the AI-chat stream-perf PR:

- Drop the unused `metadata` param from the `msg` test factory in
  message-item.test.ts; no caller passed it.
- Add a per-part-kind coupling guard to message-signature.test.ts that, for
  each part kind rendered today (text, reasoning, tool-*) plus the metadata
  banners, asserts that mutating a field the MessageItem render body DRAWS
  flips messageSignature — an executable lock for the load-bearing memo
  invariant documented in message-signature.ts.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.github/workflows/test.yml

@@ -15,6 +15,38 @@ permissions:
 jobs:
   test:
     runs-on: ubuntu-latest
+    # Real Postgres + Redis so the server integration suite (`*.int-spec.ts`,
+    # behind `pnpm --filter server test:int`) runs in CI (red-team finding #7).
+    # Without it, cost-cap / FK-cascade / jsonb-round-trip / real-apply tests
+    # only ran locally, so regressions in those paths stayed green in CI.
+    # Postgres uses the pgvector image because migrations create vector columns
+    # and global-setup runs `CREATE EXTENSION vector`. Credentials/db match the
+    # defaults in apps/server/test/integration/db.ts + global-setup.ts
+    # (docmost / docmost_dev_pw, maintenance db `docmost`, redis on 6379), so no
+    # TEST_*_URL overrides are needed.
+    services:
+      postgres:
+        image: pgvector/pgvector:pg18
+        env:
+          POSTGRES_USER: docmost
+          POSTGRES_PASSWORD: docmost_dev_pw
+          POSTGRES_DB: docmost
+        ports:
+          - 5432:5432
+        options: >-
+          --health-cmd "pg_isready -U docmost"
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
+      redis:
+        image: redis:7
+        ports:
+          - 6379:6379
+        options: >-
+          --health-cmd "redis-cli ping"
+          --health-interval 10s
+          --health-timeout 5s
+          --health-retries 5
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -36,5 +68,12 @@ jobs:
       - name: Build editor-ext
         run: pnpm --filter @docmost/editor-ext build
 
-      - name: Run tests
+      - name: Run unit tests
         run: pnpm -r test
+
+      # Integration suite against the real Postgres/Redis services above. Runs
+      # the FK-cascade, cost-cap, jsonb-round-trip and real-apply specs that the
+      # unit run (mocks only) cannot cover. global-setup drops/recreates the
+      # isolated `docmost_test` DB and migrates it to latest.
+      - name: Run server integration tests
+        run: pnpm --filter server test:int

CHANGELOG.md

@@ -12,10 +12,21 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- **Persistent AI-chat history as the source of truth + server-side export.**
+  An assistant turn is now persisted to the database step by step: the row is
+  inserted upfront as `streaming` and updated as each agent step finishes, then
+  finalized once to `completed`/`error`/`aborted`. A process that dies mid-turn
+  keeps every finished step, and a startup sweep flips any dangling `streaming`
+  row (untouched for 10 minutes) to `aborted`. Chat "Copy" now exports
+  server-side from these rows (`POST /ai-chat/export`) rather than from live
+  client state, so the export is identical whether a chat is freshly streaming,
+  just switched to, or reloaded — and is available from the first turn of a new
+  chat. (#183, #174)
+
 - **AI-agent attribution for MCP writes.** Comments (and pages) created through
   the MCP endpoint by a dedicated agent account are now badged as "AI", with
   unspoofable provenance derived from a per-user `is_agent` flag (not from the
-  request body). **Operator setup:** use a *dedicated* service account for the
+  request body). **Operator setup:** use a _dedicated_ service account for the
   MCP fallback and set the flag with SQL —
   `UPDATE users SET is_agent = true WHERE email = '<mcp-account>'`. Never flag a
   human or shared account, or its normal edits get mis-attributed as AI. See the
@@ -32,6 +43,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   OpenRouter, etc.; `openai` uses the official provider (real-OpenAI
   reasoning-model request shaping). Chosen explicitly rather than inferred from
   the base URL, since a custom URL can front real OpenAI too. (#175, #177)
+- **Per-MCP-server instructions in the agent prompt.** Each external MCP server
+  now has an admin-authored `instructions` field ("how/when to use this server's
+  tools") that is injected into the agent's system prompt next to that server's
+  tool descriptions. Trusted text, rendered inside the prompt safety sandwich;
+  shown only for a server that actually connected and contributed ≥1 callable
+  tool. (#180)
+- **Footnote multi-backlinks.** A footnote referenced more than once now shows a
+  back-link per reference (↩ a b c …), each scrolling to its own occurrence, like
+  Pandoc/Wikipedia; a single-reference footnote keeps the plain ↩. (#168)
 
 ### Changed
 
@@ -58,6 +78,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- **AI chat: the desktop app no longer freezes at 100% CPU on long agent runs.**
+  `useChat` re-rendered on every streamed token and `MessageItem`/`ReasoningBlock`
+  re-parsed the whole transcript markdown (marked + DOMPurify) on every delta, so
+  per-turn work grew quadratically and saturated the main thread. The stream is now
+  throttled (`experimental_throttle`) to ~20 Hz and each finalized message row /
+  markdown part / reasoning block is memoized, so a long turn no longer re-parses
+  already-finished content. (#182)
 - **Editor: caret/selection landed on the wrong line when clicking inside code
   blocks and footnotes.** The affected NodeViews rendered their non-editable
   chrome (language menu, footnotes heading, footnote number marker) before the
@@ -67,6 +94,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   are nudged after a paste to refresh stale hit-testing geometry. The caret
   symptom is macOS-specific and was confirmed manually on macOS; the automated
   guard pins the DOM-order invariant, not the caret behavior itself. (#146, #147)
+- **AI chat: the live token counter now ticks between agent steps.** During a
+  multi-step turn the header token badge (and the "Thinking… · N tokens" line)
+  no longer froze on the previous step's authoritative usage; the current step's
+  estimate is combined per-component with `max`, so the count rises smoothly and
+  never jumps backwards. (#163)
 
 ## [0.93.0] - 2026-06-21
 
@@ -150,8 +182,7 @@ embeds — plus a large batch of security hardening and test coverage.
 - Page templates: import `ThrottleModule` so collab boots, never strand an
   in-flight page-embed id, and add defense-in-depth workspace checks.
 - Pages: `movePage` cycle guard with no phantom `PAGE_MOVED` event.
-- Import: surface the real error cause from `/pages/import` instead of a generic
-  400.
+- Import: surface the real error cause from `/pages/import` instead of a generic 400.
 
 ### Security
 

apps/client/public/locales/en-US/translation.json

@@ -258,6 +258,7 @@
   "Copy to space": "Copy to space",
   "Copy chat": "Copy chat",
   "Copied": "Copied",
+  "Failed to export chat": "Failed to export chat",
   "Duplicate": "Duplicate",
   "Select a user": "Select a user",
   "Select a group": "Select a group",
@@ -710,6 +711,7 @@
   "Authorization header": "Authorization header",
   "Tool allowlist": "Tool allowlist",
   "Optional. Leave empty to allow all tools the server exposes.": "Optional. Leave empty to allow all tools the server exposes.",
+  "Optional guidance for the agent on how and when to use this server's tools. Injected into the system prompt. The server's tools are namespaced as \"<server name>_*\".": "Optional guidance for the agent on how and when to use this server's tools. Injected into the system prompt. The server's tools are namespaced as \"<server name>_*\".",
   "Test": "Test",
   "Available tools": "Available tools",
   "No tools available": "No tools available",
@@ -1077,6 +1079,8 @@
   "Undo": "Undo",
   "Redo": "Redo",
   "Backlinks": "Backlinks",
+  "Back to references": "Back to references",
+  "Back to reference {{label}}": "Back to reference {{label}}",
   "Last updated by": "Last updated by",
   "Last updated": "Last updated",
   "Stats": "Stats",

apps/client/public/locales/ru-RU/translation.json

@@ -257,6 +257,7 @@
   "Copy": "Копировать",
   "Copy to space": "Копировать в пространство",
   "Copied": "Скопировано",
+  "Failed to export chat": "Не удалось экспортировать чат",
   "Duplicate": "Дублировать",
   "Select a user": "Выберите пользователя",
   "Select a group": "Выберите группу",
@@ -405,6 +406,8 @@
   "Footnote {{number}}": "Сноска {{number}}",
   "Go to footnote": "Перейти к сноске",
   "Back to reference": "Вернуться к ссылке",
+  "Back to references": "Вернуться к ссылкам",
+  "Back to reference {{label}}": "Вернуться к ссылке {{label}}",
   "Empty footnote": "Пустая сноска",
   "Math inline": "Строчная формула",
   "Insert inline math equation.": "Вставить математическое выражение в строку.",
@@ -749,6 +752,8 @@
   "Manage API keys for all users in the workspace. View the <anchor>API documentation</anchor> for usage details.": "Управляйте API-ключами для всех пользователей в рабочем пространстве. Смотрите <anchor>документацию по API</anchor> для получения информации об использовании.",
   "View the <anchor>API documentation</anchor> for usage details.": "Смотрите <anchor>документацию по API</anchor> для получения информации об использовании.",
   "View the <anchor>MCP documentation</anchor>.": "Смотрите <anchor>документацию по MCP</anchor>.",
+  "Instructions": "Инструкции",
+  "Optional guidance for the agent on how and when to use this server's tools. Injected into the system prompt. The server's tools are namespaced as \"<server name>_*\".": "Необязательное указание агенту, как и когда использовать инструменты этого сервера. Добавляется в системный промпт. Инструменты сервера именуются с префиксом «<имя сервера>_*».",
   "Sources": "Источники",
   "AI Answers not available for attachments": "Ответы ИИ недоступны для вложений",
   "No answer available": "Ответ недоступен",

apps/client/src/features/ai-chat/components/ai-chat-window.tsx

@@ -6,7 +6,6 @@ import {
   useRef,
   useState,
 } from "react";
-import { type UIMessage } from "@ai-sdk/react";
 import { Group, Loader, Tooltip } from "@mantine/core";
 import {
   IconArrowsDiagonal,
@@ -40,7 +39,7 @@ import {
 } from "@/features/ai-chat/queries/ai-chat-query.ts";
 import ConversationList from "@/features/ai-chat/components/conversation-list.tsx";
 import ChatThread from "@/features/ai-chat/components/chat-thread.tsx";
-import { buildChatMarkdown } from "@/features/ai-chat/utils/chat-markdown.ts";
+import { exportAiChat } from "@/features/ai-chat/services/ai-chat-service.ts";
 import { useChatSession } from "@/features/ai-chat/hooks/use-chat-session.ts";
 import {
   shouldCollapseOnOutsidePointer,
@@ -121,7 +120,7 @@ function clampGeom(g: {
  * ported from the GitmostAgent.jsx design.
  */
 export default function AiChatWindow() {
-  const { t } = useTranslation();
+  const { t, i18n } = useTranslation();
   const clipboard = useClipboard({ timeout: 500 });
   const queryClient = useQueryClient();
   const [windowOpen, setWindowOpen] = useAtom(aiChatWindowOpenAtom);
@@ -162,30 +161,11 @@ export default function AiChatWindow() {
   const { data: messageRows, isLoading: messagesLoading } =
     useAiChatMessagesQuery(activeChatId ?? undefined);
 
-  // Live snapshot of the active thread's useChat state, kept up to date by
-  // ChatThread. Lets the export include the in-progress (not-yet-persisted)
-  // streaming turn. A ref avoids re-rendering this window on every token.
-  const liveThreadRef = useRef<{
-    messages: UIMessage[];
-    isStreaming: boolean;
-    banner: string | null;
-  }>({
-    messages: [],
-    isStreaming: false,
-    banner: null,
-  });
-
   // Live turn-token total (reasoning + output) for the in-flight turn, pushed up
   // (THROTTLED to ~8 Hz inside ChatThread) so the header badge ticks mid-stream.
   // `null` means no turn is in flight -> the badge falls back to the persisted
   // context size below.
   const [liveTurnTokens, setLiveTurnTokens] = useState<number | null>(null);
-  // Whether the on-screen thread currently holds at least one message. Reported
-  // reactively by ChatThread (the live snapshot lives in a non-reactive ref). This
-  // lets the "Copy chat" button stay available for a brand-new, not-yet-persisted
-  // chat whose first turn is in flight or was interrupted — that case has no
-  // persisted rows yet, so a persisted-rows-only gate would hide the button (#174).
-  const [hasLiveContent, setHasLiveContent] = useState(false);
 
   // The page the user is currently viewing. AiChatWindow lives in a pathless
   // parent layout route, so useParams() can't see :pageSlug. Match the full
@@ -214,6 +194,7 @@ export default function AiChatWindow() {
     threadKey,
     waitingForHistory,
     onTurnFinished,
+    onServerChatId,
     cancelPendingAdoption,
   } = useChatSession({
     activeChatId,
@@ -254,20 +235,19 @@ export default function AiChatWindow() {
     [cancelPendingAdoption, setActiveChatId, setDraft, setSelectedRoleId],
   );
 
-  // The active chat object (for its title) and an export gate: only enable the
-  // export button when an existing chat with loaded persisted rows is active.
+  // The active chat object (for its title) and an export gate. The export is now
+  // SERVER-sourced (the DB is the single source of truth — #183): the assistant
+  // row is persisted upfront + per step, so even a brand-new chat whose first
+  // turn is streaming/interrupted has a server row to render. Enable the button
+  // whenever a persisted chat is active (`activeChatId` is set). For a BRAND-NEW
+  // chat that id is adopted EARLY — at the stream's `start` chunk via
+  // onServerChatId (#174) — so the Copy button is available during the first
+  // turn's stream, not only after it terminates.
   const activeChat = useMemo(
     () => chats?.items?.find((c) => c.id === activeChatId) ?? null,
     [chats, activeChatId],
   );
-  // Export is available when there is anything to export: either persisted rows
-  // for the active chat, OR a live on-screen thread with at least one message.
-  // The live arm covers a brand-new chat whose first turn is streaming or was
-  // interrupted before the server persisted any row (#174); the persisted arm is
-  // the steady-state path for an already-saved chat (#160).
-  const canExport =
-    hasLiveContent ||
-    (!!activeChatId && !!messageRows && messageRows.length > 0);
+  const canExport = !!activeChatId;
 
   // The role to display in the header and as the assistant's name. Prefer the
   // persisted role of an existing chat (chat-list JOIN); fall back to the role
@@ -284,53 +264,21 @@ export default function AiChatWindow() {
     return picked ? { name: picked.name, emoji: picked.emoji } : null;
   }, [activeChat, enabledRoles, selectedRoleId]);
 
-  // Build a Markdown export from the already-loaded persisted rows (no network
-  // call) and copy it to the clipboard. The "Copied" notification is the
-  // feedback.
-  const handleCopy = useCallback(() => {
-    // Export gate. There must be SOMETHING to export — either a live on-screen
-    // message or a persisted row. A brand-new chat whose first turn is streaming
-    // or was interrupted has live messages but no persisted rows yet; it still
-    // exports the on-screen thread WYSIWYG (#174). Only a truly empty chat (no
-    // live messages and no rows) is non-exportable (the button is hidden too —
-    // see `canExport`).
-    const live = liveThreadRef.current;
-    const hasRows = !!messageRows && messageRows.length > 0;
-    if (live.messages.length === 0 && !hasRows) return;
-    // WYSIWYG export: the live on-screen messages ARE the document (so a partial
-    // reply from an interrupted turn — which never reached the persisted rows —
-    // is exported just as it appears). The persisted rows enrich each live
-    // message (token usage / error / timestamp) by id and serve as the fallback
-    // when the live mirror is empty. The on-screen banner is appended too. See
-    // issues #160 and #174. `chatId` may be null for a not-yet-saved chat — use a
-    // placeholder so the header line still renders.
-    const markdown = buildChatMarkdown({
-      title: activeChat?.title ?? null,
-      chatId: activeChatId ?? "unsaved",
-      live: live.messages.map((m) => ({
-        id: m.id,
-        role: m.role,
-        parts: (m.parts ?? []) as { type: string; text?: string }[],
-        metadata: m.metadata as
-          | {
-              usage?: {
-                inputTokens?: number;
-                outputTokens?: number;
-                totalTokens?: number;
-                reasoningTokens?: number;
-              };
-              error?: string;
-            }
-          | undefined,
-      })),
-      rows: messageRows,
-      isStreaming: live.isStreaming,
-      banner: live.banner,
-      t,
-    });
-    clipboard.copy(markdown);
-    notifications.show({ message: t("Copied") });
-  }, [activeChatId, messageRows, activeChat, clipboard, t]);
+  // Fetch the server-rendered Markdown export and copy it to the clipboard. The
+  // server is the single source of truth (#183): it renders the transcript from
+  // the persisted rows — including an interrupted turn's in-progress row — so the
+  // export is identical whether the chat is freshly streaming, just switched to,
+  // or reloaded. The `lang` of the active i18n drives the few localized labels.
+  const handleCopy = useCallback(async () => {
+    if (!activeChatId) return;
+    try {
+      const markdown = await exportAiChat(activeChatId, i18n.language);
+      clipboard.copy(markdown);
+      notifications.show({ message: t("Copied") });
+    } catch {
+      notifications.show({ message: t("Failed to export chat"), color: "red" });
+    }
+  }, [activeChatId, clipboard, t, i18n.language]);
 
   // Current context size for the active chat: how much the conversation now
   // occupies in the model's context window — NOT the cumulative tokens spent.
@@ -685,9 +633,8 @@ export default function AiChatWindow() {
               onRolePicked={(role) => setSelectedRoleId(role.id)}
               assistantName={currentRole?.name}
               onTurnFinished={onTurnFinished}
-              liveStateRef={liveThreadRef}
+              onServerChatId={onServerChatId}
               onLiveTurnTokens={setLiveTurnTokens}
-              onLiveContentChange={setHasLiveContent}
             />
           )}
         </div>

apps/client/src/features/ai-chat/components/ai-chat.module.css

@@ -55,6 +55,45 @@
     padding-inline-start: 1.4em;
 }
 
+/* GFM tables in assistant markdown. The chat lives in a NARROW side panel, so a
+   wide LLM table must scroll horizontally instead of collapsing its columns:
+   `.markdown` sets `word-break: break-word`, which (with the default table
+   layout) shrinks columns to a single glyph and wraps headers mid-word
+   ("Секция" -> "Секци / я"). Make the table a horizontally scrollable block,
+   give cells a readable minimum width, and restore word-boundary wrapping. */
+.markdown table {
+    display: block;
+    /* lets the table scroll horizontally on its own */
+    max-width: 100%;
+    overflow-x: auto;
+    border-collapse: collapse;
+    margin-block-end: 0.5em;
+}
+
+.markdown th,
+.markdown td {
+    border: 1px solid light-dark(var(--mantine-color-gray-3), var(--mantine-color-dark-4));
+    padding: 3px 8px;
+    /* readable floor; the block scrolls when the row exceeds the panel */
+    min-width: 6em;
+    text-align: left;
+    vertical-align: top;
+    /* cancel the inherited break-word so words don't split mid-glyph */
+    word-break: normal;
+    /* still wrap genuinely long words / URLs at the cell edge */
+    overflow-wrap: break-word;
+}
+
+.markdown th {
+    background: light-dark(var(--mantine-color-gray-1), var(--mantine-color-dark-5));
+    font-weight: 600;
+}
+
+/* GFM wraps cell text in <p>; drop its default block margin inside cells. */
+.markdown table p {
+    margin: 0;
+}
+
 /* Animated three-dot "typing" indicator shown while the agent is thinking but
    has not yet produced any visible text/tool parts. */
 .typingDots {
@@ -122,7 +161,11 @@
     margin-top: 4px;
     font-size: var(--mantine-font-size-xs);
     color: light-dark(var(--mantine-color-gray-7), var(--mantine-color-dark-1));
-    white-space: pre-wrap;
+    /* NOTE: `white-space: pre-wrap` is intentionally NOT set here. On the
+       rendered markdown <div> it would turn the newlines between block tags
+       (</li>\n<li>, </p>\n<ol>) into visible blank lines/indents on top of the
+       margins. The plain-text fallback <Text> that needs pre-wrap sets it
+       inline itself (see reasoning-block.tsx). */
 }
 
 .reasoningText p {

apps/client/src/features/ai-chat/components/chat-thread.tsx

@@ -1,11 +1,4 @@
-import {
-  useCallback,
-  useEffect,
-  useMemo,
-  useRef,
-  useState,
-  type MutableRefObject,
-} from "react";
+import { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import { generateId } from "ai";
 import { ActionIcon, Box, Group, Stack, Text } from "@mantine/core";
 import { IconClockHour4, IconX } from "@tabler/icons-react";
@@ -36,6 +29,14 @@ import {
 } from "@/features/ai-chat/utils/queue-helpers.ts";
 import classes from "@/features/ai-chat/components/ai-chat.module.css";
 
+// Throttle how often the streamed `messages` state triggers a re-render. Without
+// it, useChat updates state on EVERY token, so the whole transcript's markdown
+// (marked + DOMPurify) is re-parsed per token — on a long agent run that grows
+// into a quadratic CPU storm that pins the main thread and freezes the UI.
+// ~50ms (20 Hz) keeps streaming visually smooth while decoupling re-render cost
+// from the token rate.
+const STREAM_THROTTLE_MS = 50;
+
 /** The page the user is currently viewing, sent as chat context. */
 export interface OpenPageContext {
   id: string;
@@ -68,30 +69,18 @@ interface ChatThreadProps {
    *  authoritative id the server streamed on the assistant message metadata, or
    *  undefined on a failed turn — see adopt-chat-id.ts for the full #137 design. */
   onTurnFinished: (serverChatId?: string) => void;
-  /** Parent-owned ref that this thread keeps updated with its live useChat
-   *  snapshot (full message list + streaming flag), so the header's
-   *  "Copy chat" export can include the in-progress, not-yet-persisted
-   *  assistant message. A ref (not state) avoids re-rendering the parent on
-   *  every streamed delta. */
-  liveStateRef?: MutableRefObject<{
-    messages: UIMessage[];
-    isStreaming: boolean;
-    banner: string | null;
-  }>;
+  /** Called EARLY (at the stream's `start` chunk) with the authoritative server
+   *  chat id streamed on the assistant message metadata, so a brand-new chat
+   *  adopts its real id WHILE the first turn is still streaming (#174 — makes the
+   *  Copy/export button available mid-stream). Distinct from onTurnFinished,
+   *  which fires only at the terminal outcome. */
+  onServerChatId?: (serverChatId?: string) => void;
   /** Reports the live turn-token total (reasoning + output) for the in-flight
    *  turn so the parent can show a header badge that ticks mid-stream. THROTTLED
    *  here (~8 Hz) so the parent re-renders a handful of times a second, not on
    *  every streamed delta. Called with `null` when no turn is in flight (the
    *  parent then reverts the badge to the persisted context size). */
   onLiveTurnTokens?: (tokens: number | null) => void;
-  /** Reports whether the live thread currently holds at least one message, so the
-   *  parent can gate the "Copy chat" button on the on-screen thread rather than on
-   *  the persisted rows alone. This stays truthy for a brand-new, not-yet-saved
-   *  chat the moment its first user message appears — so an interrupted very first
-   *  turn (no persisted rows yet) is still exportable (#174). Called with `false`
-   *  on unmount so a thread torn down by `key` on chat switch can't leave the
-   *  button enabled for the next, possibly empty, chat. */
-  onLiveContentChange?: (hasContent: boolean) => void;
 }
 
 /**
@@ -135,9 +124,8 @@ export default function ChatThread({
   onRolePicked,
   assistantName,
   onTurnFinished,
-  liveStateRef,
+  onServerChatId,
   onLiveTurnTokens,
-  onLiveContentChange,
 }: ChatThreadProps) {
   const { t } = useTranslation();
 
@@ -266,6 +254,8 @@ export default function ChatThread({
     id: chatStoreId,
     messages: initialMessages,
     transport,
+    // See STREAM_THROTTLE_MS — bounds re-render/markdown-reparse frequency.
+    experimental_throttle: STREAM_THROTTLE_MS,
     // `onFinish` (ai@6 useChat) fires from a `finally` on EVERY terminal outcome
     // — success, user Stop/abort (`isAbort`), network drop (`isDisconnect`), and
     // stream error (`isError`). Keep calling `onTurnFinished()` on all of them
@@ -306,6 +296,26 @@ export default function ChatThread({
   // Keep the flush helper pointed at the latest sendMessage instance.
   sendMessageRef.current = sendMessage;
 
+  // EARLY chat-id adoption (#174): the server streams the authoritative chat id
+  // on the assistant message metadata at the `start` chunk (message.metadata.
+  // chatId — see adopt-chat-id.ts / chatStreamMetadata). Forward it to the parent
+  // AS SOON AS it appears (mid-stream), so a brand-new chat adopts its real id
+  // WHILE the first turn is still streaming and activeChatId-gated affordances
+  // (the Copy/export button) light up immediately, instead of only at onFinish.
+  // Keyed by the last-seen id so we forward each distinct id exactly once. The
+  // parent's onServerChatId is idempotent and a no-op once the chat has an id.
+  const lastForwardedChatIdRef = useRef<string | undefined>(undefined);
+  useEffect(() => {
+    if (!onServerChatId) return;
+    const tail = messages[messages.length - 1];
+    if (tail?.role !== "assistant") return;
+    const serverChatId = extractServerChatId(tail);
+    if (!serverChatId || serverChatId === lastForwardedChatIdRef.current)
+      return;
+    lastForwardedChatIdRef.current = serverChatId;
+    onServerChatId(serverChatId);
+  }, [messages, onServerChatId]);
+
   // Live "turn was interrupted" marker for the CURRENT session. The red error
   // banner (driven by `error`) covers the error case; this covers an aborted
   // turn, distinguishing a manual Stop (`isAbort`) from a dropped connection
@@ -328,44 +338,6 @@ export default function ChatThread({
   // the SAME on-screen banner text can be mirrored into the export (issue #160).
   const errorView = error ? describeChatError(error.message ?? "", t) : null;
 
-  // The exact banner the user sees under the message list, flattened to a single
-  // string for the "Copy chat" export so the artifact records the interruption
-  // WYSIWYG. Mirrors the JSX precedence below: error first, else the stop notice.
-  const banner = errorView
-    ? errorView.detail
-      ? `${errorView.title} — ${errorView.detail}`
-      : errorView.title
-    : stopNotice === "manual"
-      ? t("Response stopped.")
-      : stopNotice === "disconnect"
-        ? t("Connection lost — the answer was interrupted.")
-        : null;
-
-  // Mirror the live useChat snapshot into the parent-owned ref so the export
-  // (handled in AiChatWindow) can include the in-progress streaming turn AND the
-  // on-screen banner. The cleanup clears the ref on unmount so a thread torn down
-  // by `key` on chat switch can't leak its (possibly still-streaming) tail into
-  // the next chat's export before the new thread's effect repopulates the ref.
-  useEffect(() => {
-    if (!liveStateRef) return;
-    liveStateRef.current = { messages, isStreaming, banner };
-    return () => {
-      liveStateRef.current = { messages: [], isStreaming: false, banner: null };
-    };
-  }, [liveStateRef, messages, isStreaming, banner]);
-
-  // Reactively report "the live thread has content" to the parent. `liveStateRef`
-  // above is a ref (deliberately non-reactive so streaming deltas don't re-render
-  // the parent), so the export button needs a SEPARATE reactive signal to flip on
-  // for a not-yet-persisted chat. Keyed on the boolean only — identical values are
-  // a no-op setState in the parent, so this does not add per-delta re-renders.
-  const hasLiveContent = messages.length > 0;
-  useEffect(() => {
-    if (!onLiveContentChange) return;
-    onLiveContentChange(hasLiveContent);
-    return () => onLiveContentChange(false);
-  }, [onLiveContentChange, hasLiveContent]);
-
   // Report the live turn-token total to the parent header badge, THROTTLED to
   // ~8 Hz so the parent re-renders a few times a second instead of on every
   // streamed delta. The tail assistant message's reasoning+output (estimate while

apps/client/src/features/ai-chat/components/message-item-memo.test.tsx

@@ -0,0 +1,81 @@
+import { describe, expect, it, vi } from "vitest";
+import { render } from "@testing-library/react";
+import { MantineProvider } from "@mantine/core";
+import type { UIMessage } from "@ai-sdk/react";
+
+// Stub react-i18next (the component reads `useTranslation`). Mirrors the stub in
+// reasoning-block.test.tsx.
+vi.mock("react-i18next", () => ({
+  useTranslation: () => ({ t: (key: string) => key }),
+}));
+
+// Spy on `renderChatMarkdown` so we can count parse calls per text. We keep every
+// OTHER named export of markdown.ts intact via `importActual`, and override only
+// `renderChatMarkdown` with a `vi.fn()` that returns simple HTML so the component
+// still renders. This is the seam that proves the MarkdownPart memo works: a
+// finalized text part must NOT be re-parsed on a later streamed delta.
+// `vi.hoisted` so the spy exists when the hoisted `vi.mock` factory runs.
+const { renderChatMarkdownSpy } = vi.hoisted(() => ({
+  renderChatMarkdownSpy: vi.fn((text: string) => `<p>${text}</p>`),
+}));
+vi.mock("@/features/ai-chat/utils/markdown.ts", async () => {
+  const actual = await vi.importActual<
+    typeof import("@/features/ai-chat/utils/markdown.ts")
+  >("@/features/ai-chat/utils/markdown.ts");
+  return { ...actual, renderChatMarkdown: renderChatMarkdownSpy };
+});
+
+import MessageItem from "./message-item";
+
+// matchMedia (read by MantineProvider) is stubbed globally in vitest.setup.ts.
+
+const msg = (parts: UIMessage["parts"]): UIMessage =>
+  ({ id: "m1", role: "assistant", parts }) as UIMessage;
+
+const renderRow = (message: UIMessage) =>
+  render(
+    <MantineProvider>
+      <MessageItem message={message} />
+    </MantineProvider>,
+  );
+
+/** Count how many spy calls parsed exactly `text` (filtering by the first arg). */
+const callsFor = (text: string) =>
+  renderChatMarkdownSpy.mock.calls.filter((c) => c[0] === text).length;
+
+describe("MessageItem markdown memoization", () => {
+  it("does not re-parse finalized text parts when only a tail part grows", () => {
+    renderChatMarkdownSpy.mockClear();
+
+    // Two finalized text parts.
+    const first = msg([
+      { type: "text", text: "alpha" },
+      { type: "text", text: "beta" },
+    ]);
+    const { rerender } = renderRow(first);
+
+    // Both finalized parts parsed exactly once on the initial render.
+    expect(callsFor("alpha")).toBe(1);
+    expect(callsFor("beta")).toBe(1);
+
+    // A streamed delta: a NEW message object where only a third tail part grows;
+    // the first two parts' text is byte-identical.
+    const next = msg([
+      { type: "text", text: "alpha" },
+      { type: "text", text: "beta" },
+      { type: "text", text: "gamm" },
+    ]);
+    rerender(
+      <MantineProvider>
+        <MessageItem message={next} />
+      </MantineProvider>,
+    );
+
+    // The finalized parts hit the MarkdownPart memo: still parsed at most once
+    // each across BOTH renders (the resilient invariant). The only new parse is
+    // for the changed/added tail part.
+    expect(callsFor("alpha")).toBe(1);
+    expect(callsFor("beta")).toBe(1);
+    expect(callsFor("gamm")).toBe(1);
+  });
+});

apps/client/src/features/ai-chat/components/message-item.test.ts

@@ -0,0 +1,73 @@
+import { describe, expect, it, vi } from "vitest";
+import type { UIMessage } from "@ai-sdk/react";
+
+// Stub react-i18next: importing the component module pulls in `useTranslation`,
+// and we only exercise the pure `arePropsEqual` comparator (no rendering), so a
+// minimal `t` that echoes the key is enough. Mirrors the stub in
+// reasoning-block.test.tsx.
+vi.mock("react-i18next", () => ({
+  useTranslation: () => ({ t: (key: string) => key }),
+}));
+
+import { arePropsEqual } from "./message-item";
+
+/**
+ * Tests for `arePropsEqual`, the `React.memo` comparator for MessageItem. It must
+ * return false on any visible prop/content change (so the row re-renders) and
+ * true when nothing visible changed (so a finalized row is skipped). A FIXED
+ * message id is used so a content-identical clone yields an equal signature.
+ */
+const msg = (parts: UIMessage["parts"]): UIMessage =>
+  ({ id: "m1", role: "assistant", parts }) as UIMessage;
+
+const props = (
+  message: UIMessage,
+  over: Record<string, unknown> = {},
+) => ({
+  message,
+  showCitations: true,
+  neutralizeInternalLinks: false,
+  assistantName: "AI",
+  ...over,
+});
+
+describe("arePropsEqual", () => {
+  it("returns false when showCitations differs", () => {
+    const m = msg([{ type: "text", text: "answer" }]);
+    expect(
+      arePropsEqual(props(m), props(m, { showCitations: false })),
+    ).toBe(false);
+  });
+
+  it("returns false when neutralizeInternalLinks differs", () => {
+    const m = msg([{ type: "text", text: "answer" }]);
+    expect(
+      arePropsEqual(props(m), props(m, { neutralizeInternalLinks: true })),
+    ).toBe(false);
+  });
+
+  it("returns false when assistantName differs", () => {
+    const m = msg([{ type: "text", text: "answer" }]);
+    expect(
+      arePropsEqual(props(m), props(m, { assistantName: "Other" })),
+    ).toBe(false);
+  });
+
+  it("returns true on the identity fast path (same message object, equal props)", () => {
+    const m = msg([{ type: "text", text: "answer" }]);
+    expect(arePropsEqual(props(m), props(m))).toBe(true);
+  });
+
+  it("returns true for the same content in a different message object", () => {
+    const a = msg([{ type: "text", text: "answer" }]);
+    const b = msg([{ type: "text", text: "answer" }]);
+    expect(a).not.toBe(b);
+    expect(arePropsEqual(props(a), props(b))).toBe(true);
+  });
+
+  it("returns false when content changed in a different message object", () => {
+    const a = msg([{ type: "text", text: "answer" }]);
+    const b = msg([{ type: "text", text: "answer grown" }]);
+    expect(arePropsEqual(props(a), props(b))).toBe(false);
+  });
+});

apps/client/src/features/ai-chat/components/message-item.tsx

@@ -1,3 +1,4 @@
+import { memo } from "react";
 import { Box, Text } from "@mantine/core";
 import { useTranslation } from "react-i18next";
 import type { UIMessage } from "@ai-sdk/react";
@@ -10,6 +11,7 @@ import { assistantMessageHasVisibleContent } from "@/features/ai-chat/utils/mess
 import { renderChatMarkdown } from "@/features/ai-chat/utils/markdown.ts";
 import { resolveAssistantName } from "@/features/ai-chat/utils/assistant-name.ts";
 import { reasoningTokensForPart } from "@/features/ai-chat/utils/reasoning-tokens.ts";
+import { messageSignature } from "@/features/ai-chat/utils/message-signature.ts";
 import { describeChatError } from "@/features/ai-chat/utils/error-message.ts";
 import classes from "@/features/ai-chat/components/ai-chat.module.css";
 
@@ -34,6 +36,39 @@ interface MessageItemProps {
   assistantName?: string;
 }
 
+/**
+ * One assistant text part rendered as sanitized markdown. Memoized on its inputs
+ * so a finalized text part is NOT re-parsed on every streamed delta: during a
+ * turn only the actively-growing tail part changes its `text`, so every earlier
+ * part hits the memo and skips the expensive marked + DOMPurify pass. Props are
+ * primitives, so React.memo's default shallow compare is exactly right (the
+ * `text` string is compared by value).
+ */
+const MarkdownPart = memo(function MarkdownPart({
+  text,
+  neutralizeInternalLinks,
+}: {
+  text: string;
+  neutralizeInternalLinks: boolean;
+}) {
+  const html = renderChatMarkdown(text, { neutralizeInternalLinks });
+  if (html) {
+    return (
+      <div
+        className={classes.markdown}
+        // Sanitized by renderChatMarkdown (DOMPurify) before insertion.
+        dangerouslySetInnerHTML={{ __html: html }}
+      />
+    );
+  }
+  // Fallback when markdown could not render synchronously: raw text.
+  return (
+    <Text className={classes.markdown} style={{ whiteSpace: "pre-wrap" }}>
+      {text}
+    </Text>
+  );
+});
+
 /**
  * Render a single UIMessage by iterating its `parts`:
  *  - `text` parts -> sanitized markdown.
@@ -41,12 +76,13 @@ interface MessageItemProps {
  * Other part kinds (reasoning, sources, files, step-start) are ignored for v1.
  * User messages render their text as a right-aligned plain bubble.
  *
- * This component is intentionally NOT memoized: `useChat` replaces the streaming
- * assistant message with a freshly cloned object on every streamed delta, so the
- * `message` prop identity (and its `parts`) changes each tick. Re-rendering the
- * text parts on each delta is what makes the answer stream in progressively.
+ * This component is memoized (see `arePropsEqual` at the bottom) on a cheap
+ * per-message content signature: the streaming TAIL message's signature changes
+ * on each delta so it still re-renders and streams in, while finalized rows are
+ * skipped. Each text part's markdown is itself memoized via `MarkdownPart`, so a
+ * long turn no longer re-parses the whole transcript on every token.
  */
-export default function MessageItem({
+function MessageItem({
   message,
   showCitations = true,
   neutralizeInternalLinks = false,
@@ -109,24 +145,12 @@ export default function MessageItem({
           // starts with an empty text part before the first token arrives); the
           // typing indicator covers that gap until real content streams in.
           if (!part.text.trim()) return null;
-          const html = renderChatMarkdown(part.text, {
-            neutralizeInternalLinks,
-          });
-          if (html) {
-            return (
-              <div
-                key={index}
-                className={classes.markdown}
-                // Sanitized by renderChatMarkdown (DOMPurify) before insertion.
-                dangerouslySetInnerHTML={{ __html: html }}
-              />
-            );
-          }
-          // Fallback when markdown could not render synchronously: raw text.
           return (
-            <Text key={index} className={classes.markdown} style={{ whiteSpace: "pre-wrap" }}>
-              {part.text}
-            </Text>
+            <MarkdownPart
+              key={index}
+              text={part.text}
+              neutralizeInternalLinks={neutralizeInternalLinks}
+            />
           );
         }
 
@@ -177,3 +201,26 @@ export default function MessageItem({
     </Box>
   );
 }
+
+/** Skip re-rendering a message whose visible content is unchanged. The streaming
+ *  TAIL message gets a fresh object whose signature changes each delta, so it
+ *  still re-renders and streams in; every FINALIZED message is skipped, turning a
+ *  per-token whole-transcript re-render into a tail-only one. */
+export function arePropsEqual(
+  prev: MessageItemProps,
+  next: MessageItemProps,
+): boolean {
+  if (
+    prev.showCitations !== next.showCitations ||
+    prev.neutralizeInternalLinks !== next.neutralizeInternalLinks ||
+    prev.assistantName !== next.assistantName
+  ) {
+    return false;
+  }
+  // Fast path: identical message object (finalized rows keep their identity
+  // across deltas) — skip without building signatures.
+  if (prev.message === next.message) return true;
+  return messageSignature(prev.message) === messageSignature(next.message);
+}
+
+export default memo(MessageItem, arePropsEqual);

apps/client/src/features/ai-chat/components/reasoning-block.tsx

@@ -1,8 +1,9 @@
-import { useState } from "react";
+import { memo, useMemo, useState } from "react";
 import { Box, Collapse, Group, Text, UnstyledButton } from "@mantine/core";
 import { IconChevronDown } from "@tabler/icons-react";
 import { useTranslation } from "react-i18next";
 import { estimateTokens } from "@/features/ai-chat/utils/count-stream-tokens.ts";
+import { collapseBlankLines } from "@/features/ai-chat/utils/collapse-blank-lines.ts";
 import { renderChatMarkdown } from "@/features/ai-chat/utils/markdown.ts";
 import classes from "@/features/ai-chat/components/ai-chat.module.css";
 
@@ -26,14 +27,23 @@ interface ReasoningBlockProps {
  * Providers that don't stream reasoning TEXT still render this block from the
  * authoritative count alone (header only, empty body) so the cost is visible.
  */
-export default function ReasoningBlock({ text, tokens }: ReasoningBlockProps) {
+function ReasoningBlock({ text, tokens }: ReasoningBlockProps) {
   const { t } = useTranslation();
   const [open, setOpen] = useState(false);
 
   // Authoritative count wins; otherwise estimate live from the streamed text.
   const count = tokens && tokens > 0 ? tokens : estimateTokens(text);
   const trimmed = text.trim();
-  const html = trimmed ? renderChatMarkdown(trimmed, {}) : "";
+  // Memoize the markdown render so toggling `open` (or a parent re-render caused
+  // by an unrelated streamed delta) does not re-parse the reasoning text; it
+  // recomputes only when the reasoning text itself changes (while it streams in).
+  // collapseBlankLines collapses the blank-line gaps the model emits between every
+  // list item / paragraph so the reasoning renders compactly (tight lists, joined
+  // paragraphs) — ONLY here, not in the normal answer.
+  const html = useMemo(
+    () => (trimmed ? renderChatMarkdown(collapseBlankLines(trimmed), {}) : ""),
+    [trimmed],
+  );
 
   return (
     <Box className={classes.reasoningBlock} mb={6}>
@@ -81,3 +91,8 @@ export default function ReasoningBlock({ text, tokens }: ReasoningBlockProps) {
     </Box>
   );
 }
+
+// Memoized: re-renders only when `text`/`tokens` change (primitive props, default
+// shallow compare), so a parent re-render during streaming of OTHER content does
+// not re-run the markdown parse for an already-finalized reasoning block.
+export default memo(ReasoningBlock);

apps/client/src/features/ai-chat/hooks/use-chat-session.test.tsx

@@ -64,7 +64,10 @@ describe("useChatSession", () => {
     result.current.onTurnFinished(undefined);
     expect(setActiveChatId).not.toHaveBeenCalled();
     // The refetch lands with the new row => adopt it.
-    rerender({ activeChatId: null, chats: { items: [{ id: "x" }, { id: "new" }] } });
+    rerender({
+      activeChatId: null,
+      chats: { items: [{ id: "x" }, { id: "new" }] },
+    });
     expect(setActiveChatId).toHaveBeenCalledWith("new");
   });
 
@@ -88,7 +91,10 @@ describe("useChatSession", () => {
     });
     result.current.onTurnFinished(undefined);
     // a was deleted, new was added — same length, but membership changed.
-    rerender({ activeChatId: null, chats: { items: [{ id: "b" }, { id: "new" }] } });
+    rerender({
+      activeChatId: null,
+      chats: { items: [{ id: "b" }, { id: "new" }] },
+    });
     expect(setActiveChatId).toHaveBeenCalledWith("new");
   });
 
@@ -171,6 +177,40 @@ describe("useChatSession", () => {
     expect(setActiveChatId).not.toHaveBeenCalledWith("late");
   });
 
+  it("#174 early adopt: onServerChatId adopts the streamed id mid-stream (Copy button available during the first turn)", () => {
+    // Brand-new chat: no id yet. The server streams the real chat id "A" on the
+    // `start` chunk WHILE the first turn is still streaming (before onTurnFinished
+    // fires at the terminal outcome). The hook must adopt it immediately so the
+    // window's activeChatId-gated Copy/export button lights up during the stream.
+    const { result, setActiveChatId } = setup({
+      activeChatId: null,
+      chats: { items: [] },
+    });
+    result.current.onServerChatId("A");
+    expect(setActiveChatId).toHaveBeenCalledWith("A");
+  });
+
+  it("#174 early adopt is in-place: threadKey stays stable (live stream not torn down)", () => {
+    const chats = { items: [] };
+    const { result, rerender } = setup({ activeChatId: null, chats });
+    const keyBefore = result.current.threadKey;
+    result.current.onServerChatId("A");
+    // Parent reflects the adopted id back in; the SAME mount key is kept so the
+    // in-flight useChat store (the streaming turn) is preserved.
+    rerender({ activeChatId: "A", chats });
+    expect(result.current.threadKey).toBe(keyBefore);
+  });
+
+  it("#174 early adopt: no-op for an existing chat and for a missing id", () => {
+    const { result, setActiveChatId } = setup({
+      activeChatId: "chat-1",
+      chats: { items: [{ id: "chat-1" }] },
+    });
+    result.current.onServerChatId("chat-1"); // already has an id
+    result.current.onServerChatId(undefined); // no streamed id
+    expect(setActiveChatId).not.toHaveBeenCalled();
+  });
+
   it("in-place adopt keeps threadKey stable; an external switch remounts", () => {
     const chats = { items: [{ id: "B" }] };
     const { result, rerender } = setup({ activeChatId: null, chats });

apps/client/src/features/ai-chat/hooks/use-chat-session.ts

@@ -34,6 +34,13 @@ export interface UseChatSessionResult {
   /** Call when a turn finishes; `serverChatId` is the authoritative streamed id
    *  (undefined on a failed turn). Handles new-chat id adoption + invalidations. */
   onTurnFinished: (serverChatId?: string) => void;
+  /** Call EARLY (at the stream's `start` chunk) with the authoritative streamed
+   *  chat id so a brand-new chat adopts its real id WHILE its first turn is still
+   *  streaming — making `activeChatId`-gated affordances (e.g. the Copy/export
+   *  button, #174) available immediately. In-place adoption only (same mount key,
+   *  no list/messages invalidation — that is left to onTurnFinished at the end).
+   *  Idempotent and a no-op once the chat already has an id. */
+  onServerChatId: (serverChatId?: string) => void;
   /** Disarm any pending error-path new-chat fallback. The window calls this from
    *  startNewChat/selectChat so a late refetch can't yank the user back into a
    *  just-failed chat after they explicitly moved on. */
@@ -85,13 +92,10 @@ export function useChatSession(
   // `newThread`/`switchThread` to (re)mount, `adoptThread` for in-place adoption.
   // Initial: a non-null activeChatId switches to it; a null one gets a fresh
   // session key with no chat id yet.
-  const [thread, dispatch] = useReducer(
-    threadSessionReducer,
-    undefined,
-    () =>
-      activeChatId === null
-        ? newThread(`new-${generateId()}`)
-        : switchThread(activeChatId),
+  const [thread, dispatch] = useReducer(threadSessionReducer, undefined, () =>
+    activeChatId === null
+      ? newThread(`new-${generateId()}`)
+      : switchThread(activeChatId),
   );
 
   // Error-path fallback for new-chat id adoption. When a brand-new chat's first
@@ -150,6 +154,31 @@ export function useChatSession(
     [chats, setActiveChatId, onInvalidateChatList, onInvalidateChatMessages],
   );
 
+  // EARLY adoption (#174): adopt the authoritative streamed chat id the moment
+  // the server emits it on the `start` chunk, so a brand-new chat gets its real
+  // `activeChatId` WHILE its first turn streams — not only at terminal
+  // onTurnFinished. This makes the activeChatId-gated Copy/export button
+  // available during the first turn. Pure in-place adoption (same mount key, like
+  // the primary path) with NO invalidation: the list/messages refresh stays on
+  // onTurnFinished at the end of the turn. Reads the live id from the ref so a
+  // repeat call after adoption is a no-op (resolveAdoptedChatId only fires for a
+  // still-new chat).
+  const onServerChatId = useCallback(
+    (serverChatId?: string) => {
+      const adopted = resolveAdoptedChatId(
+        activeChatIdRef.current,
+        serverChatId,
+      );
+      if (!adopted) return;
+      activeChatIdRef.current = adopted;
+      setActiveChatId(adopted);
+      dispatch({ type: "adopt", chatId: adopted });
+      // Early adoption beat the error-path fallback to it — disarm.
+      pendingNewChatRef.current = null;
+    },
+    [setActiveChatId],
+  );
+
   // FALLBACK resolver. Armed only by onTurnFinished when a brand-new chat's first
   // turn errored before the `start` chunk (no authoritative id streamed). Once
   // the per-user list refetch lands with the just-created row, adopt the SINGLE
@@ -233,6 +262,7 @@ export function useChatSession(
     threadKey: thread.key,
     waitingForHistory,
     onTurnFinished,
+    onServerChatId,
     cancelPendingAdoption,
   };
 }

apps/client/src/features/ai-chat/services/ai-chat-service.ts

@@ -50,6 +50,24 @@ export async function deleteAiChat(chatId: string): Promise<void> {
   await api.post("/ai-chat/delete", { chatId });
 }
 
+/**
+ * Export a chat to Markdown (#183). The server renders the transcript from the
+ * persisted rows (the DB is the single source of truth — including an
+ * interrupted turn's in-progress row, persisted upfront + per step), so the
+ * client just copies the returned string. `lang` localizes the few fixed
+ * role/tool labels; defaults to English server-side when omitted.
+ */
+export async function exportAiChat(
+  chatId: string,
+  lang?: string,
+): Promise<string> {
+  const req = await api.post<{ markdown: string }>("/ai-chat/export", {
+    chatId,
+    lang,
+  });
+  return req.data.markdown;
+}
+
 /**
  * Agent roles API (`/ai-chat/roles`). `list` is available to any workspace
  * member (for the chat-creation picker); create/update/delete are admin-only
@@ -76,6 +94,8 @@ export async function updateAiRole(data: IAiRoleUpdate): Promise<IAiRole> {
 
 /** Soft-delete a role (admin). */
 export async function deleteAiRole(id: string): Promise<{ success: true }> {
-  const req = await api.post<{ success: true }>("/ai-chat/roles/delete", { id });
+  const req = await api.post<{ success: true }>("/ai-chat/roles/delete", {
+    id,
+  });
   return req.data;
 }

apps/client/src/features/ai-chat/utils/chat-markdown.test.ts

@@ -1,747 +0,0 @@
-import { describe, it, expect } from "vitest";
-import { buildChatMarkdown } from "@/features/ai-chat/utils/chat-markdown.ts";
-import type { IAiChatMessageRow } from "@/features/ai-chat/types/ai-chat.types.ts";
-
-/**
- * Tests for the client-only Markdown export builder. The output embeds a live
- * `new Date().toISOString()` export timestamp; we never assert that value, only
- * the deterministic structure (headings, numbering, fenced blocks, totals).
- *
- * A pass-through translator keeps role/tool labels predictable so the
- * structural assertions are stable without an i18n runtime.
- */
-const t = (key: string, values?: Record<string, unknown>): string => {
-  if (values && typeof values.name === "string") {
-    return key.replace("{{name}}", values.name);
-  }
-  return key;
-};
-
-function row(partial: Partial<IAiChatMessageRow>): IAiChatMessageRow {
-  return {
-    id: partial.id ?? "id",
-    role: partial.role ?? "user",
-    content: partial.content ?? null,
-    metadata: partial.metadata ?? null,
-    createdAt: partial.createdAt ?? "2026-06-21T00:00:00.000Z",
-  };
-}
-
-describe("buildChatMarkdown — structure", () => {
-  it("emits the title heading, chat id and message count", () => {
-    const md = buildChatMarkdown({
-      title: "My chat",
-      chatId: "chat-123",
-      rows: [],
-      t,
-    });
-    expect(md).toContain("# My chat");
-    expect(md).toContain("- Chat ID: `chat-123`");
-    expect(md).toContain("- Messages: 0");
-    expect(md).toContain("- Exported:"); // timestamp present, value not asserted
-  });
-
-  it("falls back to the translated 'Untitled chat' for empty/blank titles", () => {
-    expect(
-      buildChatMarkdown({ title: null, chatId: "c", rows: [], t }),
-    ).toContain("# Untitled chat");
-    expect(
-      buildChatMarkdown({ title: "   ", chatId: "c", rows: [], t }),
-    ).toContain("# Untitled chat");
-  });
-
-  it("numbers rows sequentially with role headings", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({ role: "user", content: "hi" }),
-        row({ role: "assistant", content: "hello" }),
-        row({ role: "user", content: "again" }),
-      ],
-      t,
-    });
-    expect(md).toContain("## 1. You");
-    expect(md).toContain("## 2. AI agent");
-    expect(md).toContain("## 3. You");
-    // Heading numbering is strictly index+1, not e.g. role-relative.
-    expect(md).not.toContain("## 0.");
-  });
-
-  it("renders the per-row text content from `content` when no metadata.parts", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [row({ role: "user", content: "plain body" })],
-      t,
-    });
-    expect(md).toContain("plain body");
-  });
-});
-
-describe("buildChatMarkdown — text parts", () => {
-  it("skips empty / whitespace-only text parts", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "ignored-content",
-          metadata: {
-            parts: [
-              { type: "text", text: "   " },
-              { type: "text", text: "" },
-              { type: "text", text: "kept line" },
-              // eslint-disable-next-line @typescript-eslint/no-explicit-any
-            ] as any,
-          },
-        }),
-      ],
-      t,
-    });
-    expect(md).toContain("kept line");
-    // Whitespace-only part contributed no block of its own.
-    expect(md).not.toContain("   \n\n");
-    // When metadata.parts exists, the plain `content` fallback is NOT used.
-    expect(md).not.toContain("ignored-content");
-  });
-});
-
-describe("buildChatMarkdown — tool parts", () => {
-  it("renders a tool label, name, state and fenced Input/Output blocks", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "",
-          metadata: {
-            parts: [
-              {
-                type: "tool-getPage",
-                state: "output-available",
-                input: { pageId: "p1" },
-                output: { id: "p1", title: "Home" },
-                // eslint-disable-next-line @typescript-eslint/no-explicit-any
-              } as any,
-            ],
-          },
-        }),
-      ],
-      t,
-    });
-    // Known tool name maps to its label key; raw name in backticks; done state.
-    expect(md).toContain("**Tool: Read page** (`getPage`) — done");
-    expect(md).toContain("Input:");
-    expect(md).toContain("Output:");
-    // Fenced JSON blocks contain the stringified payloads.
-    expect(md).toContain('"pageId": "p1"');
-    expect(md).toContain('"title": "Home"');
-    expect(md).toContain("```json");
-  });
-
-  it("renders the generic label for an unknown tool and surfaces errorText", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "",
-          metadata: {
-            parts: [
-              {
-                type: "tool-mysteryTool",
-                state: "output-error",
-                input: { a: 1 },
-                errorText: "boom",
-                // eslint-disable-next-line @typescript-eslint/no-explicit-any
-              } as any,
-            ],
-          },
-        }),
-      ],
-      t,
-    });
-    expect(md).toContain(
-      "**Tool: Ran tool mysteryTool** (`mysteryTool`) — error",
-    );
-    expect(md).toContain("**Error:** boom");
-  });
-
-  it("does not throw on a circular tool input (falls back to String)", () => {
-    // eslint-disable-next-line @typescript-eslint/no-explicit-any
-    const circular: any = {};
-    circular.self = circular;
-    expect(() =>
-      buildChatMarkdown({
-        title: "t",
-        chatId: "c",
-        rows: [
-          row({
-            role: "assistant",
-            content: "",
-            metadata: {
-              parts: [
-                {
-                  type: "tool-getPage",
-                  state: "input-available",
-                  input: circular,
-                  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-                } as any,
-              ],
-            },
-          }),
-        ],
-        t,
-      }),
-    ).not.toThrow();
-  });
-});
-
-describe("buildChatMarkdown — fence anti-breakout", () => {
-  it("lengthens the delimiter so embedded ``` cannot break out of the block", () => {
-    // Tool input whose stringified string form contains a literal ``` run.
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "",
-          metadata: {
-            parts: [
-              {
-                type: "tool-getPage",
-                state: "output-available",
-                // A bare string passes through stringify() verbatim.
-                input: "before ``` after",
-                output: "x",
-                // eslint-disable-next-line @typescript-eslint/no-explicit-any
-              } as any,
-            ],
-          },
-        }),
-      ],
-      t,
-    });
-    // The fence around the 3-backtick content must use at least 4 backticks so
-    // the embedded ``` run cannot terminate the block.
-    expect(md).toContain("````json\nbefore ``` after\n````");
-    // Robust anti-breakout check: the opening fence delimiter is strictly
-    // longer than the longest backtick run inside the wrapped content. (A naive
-    // `not.toContain("```json...")` is a false negative — a 4-backtick fence
-    // textually contains the 3-backtick substring.)
-    const open = md.match(/(`{3,})json\nbefore/);
-    expect(open).not.toBeNull();
-    expect(open![1].length).toBeGreaterThan(3); // > the 3-backtick run in content
-  });
-
-  it("uses a 5-backtick fence when the content has a 4-backtick run", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "",
-          metadata: {
-            parts: [
-              {
-                type: "tool-getPage",
-                state: "output-available",
-                input: "a ```` b",
-                // eslint-disable-next-line @typescript-eslint/no-explicit-any
-              } as any,
-            ],
-          },
-        }),
-      ],
-      t,
-    });
-    expect(md).toContain("`````json\na ```` b\n`````");
-  });
-});
-
-describe("buildChatMarkdown — token totals", () => {
-  it("prints the total-tokens line only when the summed usage is > 0", () => {
-    const withTokens = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "x",
-          metadata: { usage: { inputTokens: 10, outputTokens: 5 } },
-        }),
-      ],
-      t,
-    });
-    expect(withTokens).toContain("- Total tokens: 15");
-    // Per-row usage footer too.
-    expect(withTokens).toContain("_Tokens — in: 10, out: 5, total: 15_");
-  });
-
-  it("omits the total-tokens line when the sum is 0 / usage absent", () => {
-    const noTokens = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({ role: "user", content: "hi" }),
-        row({
-          role: "assistant",
-          content: "x",
-          metadata: { usage: { inputTokens: 0, outputTokens: 0 } },
-        }),
-      ],
-      t,
-    });
-    expect(noTokens).not.toContain("- Total tokens:");
-  });
-
-  it("uses totalTokens when present rather than summing in/out", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "x",
-          metadata: {
-            usage: { inputTokens: 3, outputTokens: 4, totalTokens: 99 },
-          },
-        }),
-      ],
-      t,
-    });
-    expect(md).toContain("- Total tokens: 99");
-  });
-
-  it("appends the reasoning figure to the row footer when reasoningTokens > 0", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "x",
-          metadata: {
-            usage: { inputTokens: 10, outputTokens: 8, reasoningTokens: 3 },
-          },
-        }),
-      ],
-      t,
-    });
-    expect(md).toContain("_Tokens — in: 10, out: 8, reasoning: 3, total: 18_");
-  });
-
-  it("omits the reasoning figure when reasoningTokens is 0 / absent", () => {
-    const zero = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "x",
-          metadata: {
-            usage: { inputTokens: 10, outputTokens: 5, reasoningTokens: 0 },
-          },
-        }),
-      ],
-      t,
-    });
-    expect(zero).toContain("_Tokens — in: 10, out: 5, total: 15_");
-    expect(zero).not.toContain("reasoning:");
-
-    const absent = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          role: "assistant",
-          content: "x",
-          metadata: { usage: { inputTokens: 10, outputTokens: 5 } },
-        }),
-      ],
-      t,
-    });
-    expect(absent).not.toContain("reasoning:");
-  });
-});
-
-// A minimal on-screen (live) message, matching the subset buildChatMarkdown reads.
-function live(partial: {
-  id?: string;
-  role?: string;
-  parts?: { type: string; text?: string }[];
-  metadata?: { usage?: Record<string, number>; error?: string };
-}) {
-  return {
-    id: partial.id ?? "live-id",
-    role: partial.role ?? "assistant",
-    parts: partial.parts ?? [],
-    metadata: partial.metadata,
-  };
-}
-
-describe("buildChatMarkdown — live (WYSIWYG) source", () => {
-  it("uses the live messages as the document (what's on screen), numbered from 1", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      // Persisted rows hold only the user turn; the assistant reply is live-only.
-      rows: [row({ id: "u1", role: "user", content: "persisted user" })],
-      live: [
-        live({
-          id: "u1",
-          role: "user",
-          parts: [{ type: "text", text: "on-screen user" }],
-        }),
-        live({
-          id: "a1",
-          role: "assistant",
-          parts: [{ type: "text", text: "on-screen reply" }],
-        }),
-      ],
-      isStreaming: false,
-      t,
-    });
-    expect(md).toContain("## 1. You");
-    expect(md).toContain("## 2. AI agent");
-    expect(md).toContain("on-screen user");
-    expect(md).toContain("on-screen reply");
-    // Message count reflects the LIVE document, not rows + live.
-    expect(md).toContain("- Messages: 2");
-  });
-
-  it("captures a partial reply from an interrupted (non-streaming) turn — no 'generating' note", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [row({ id: "u1", role: "user", content: "q" })],
-      live: [
-        live({ id: "u1", role: "user", parts: [{ type: "text", text: "q" }] }),
-        live({
-          id: "a-live",
-          role: "assistant",
-          parts: [{ type: "text", text: "partial plan before the drop" }],
-        }),
-      ],
-      isStreaming: false, // the stream dropped — not streaming anymore
-      banner: "Connection lost — the answer was interrupted.",
-      t,
-    });
-    // The partial assistant answer that was on screen IS in the export.
-    expect(md).toContain("partial plan before the drop");
-    // It is NOT flagged still-generating (the turn is over, just interrupted).
-    expect(md).not.toContain("still being generated");
-    // The on-screen banner is recorded at the end.
-    expect(md).toContain("Connection lost — the answer was interrupted.");
-  });
-
-  it("flags ONLY the tail assistant as still generating, and only while streaming", () => {
-    const streaming = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [],
-      live: [
-        live({
-          id: "a",
-          role: "assistant",
-          parts: [{ type: "text", text: "done earlier" }],
-        }),
-        live({
-          id: "u",
-          role: "user",
-          parts: [{ type: "text", text: "next q" }],
-        }),
-        live({
-          id: "b",
-          role: "assistant",
-          parts: [{ type: "text", text: "streaming now" }],
-        }),
-      ],
-      isStreaming: true,
-      t,
-    });
-    // Exactly one "still being generated" note (the tail assistant).
-    expect(streaming.match(/still being generated/g)?.length).toBe(1);
-
-    const idle = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [],
-      live: [
-        live({
-          id: "b",
-          role: "assistant",
-          parts: [{ type: "text", text: "final" }],
-        }),
-      ],
-      isStreaming: false,
-      t,
-    });
-    expect(idle).not.toContain("still being generated");
-  });
-
-  it("does NOT flag a completed assistant as generating when the streaming tail is a user message", () => {
-    // The `status === "submitted"` window: the user just sent, isStreaming is
-    // already true, but the new assistant turn has no message yet so the tail is
-    // the USER message. The previous assistant answer is complete on screen and
-    // must not be marked still-generating (WYSIWYG; regression for #160 review).
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [],
-      live: [
-        live({
-          id: "a",
-          role: "assistant",
-          parts: [{ type: "text", text: "completed answer" }],
-        }),
-        live({
-          id: "u",
-          role: "user",
-          parts: [{ type: "text", text: "the new question" }],
-        }),
-      ],
-      isStreaming: true,
-      t,
-    });
-    expect(md).toContain("completed answer");
-    expect(md).not.toContain("still being generated");
-  });
-
-  it("emits the heading + note for a streaming tail assistant with empty parts", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [row({ id: "u1", role: "user", content: "q" })],
-      live: [
-        live({ id: "u1", role: "user", parts: [{ type: "text", text: "q" }] }),
-        live({ id: "a-live", role: "assistant", parts: [] }),
-      ],
-      isStreaming: true,
-      t,
-    });
-    expect(md).toContain("## 2. AI agent");
-    expect(md).toContain("still being generated");
-  });
-});
-
-describe("buildChatMarkdown — live enrichment from persisted rows", () => {
-  it("pulls usage / error / timestamp from the persisted row matched by id", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          id: "a1",
-          role: "assistant",
-          content: "x",
-          createdAt: "2026-06-22T10:00:00.000Z",
-          metadata: {
-            usage: { inputTokens: 10, outputTokens: 5 },
-            error: "rate limited",
-          },
-        }),
-      ],
-      live: [
-        // Same id as the persisted row, but no usage/error/timestamp on the live msg.
-        live({
-          id: "a1",
-          role: "assistant",
-          parts: [{ type: "text", text: "reply" }],
-        }),
-      ],
-      isStreaming: false,
-      t,
-    });
-    expect(md).toContain("reply");
-    // Token footer + total come from the enriched row.
-    expect(md).toContain("_Tokens — in: 10, out: 5, total: 15_");
-    expect(md).toContain("- Total tokens: 15");
-    expect(md).toContain("**⚠️ Error:** rate limited");
-    // The persisted timestamp is carried into the export.
-    expect(md).toContain("<!-- 2026-06-22T10:00:00.000Z -->");
-  });
-
-  it("prefers authoritative usage already on the live message over the row's", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({
-          id: "a1",
-          role: "assistant",
-          content: "x",
-          metadata: {
-            usage: { inputTokens: 1, outputTokens: 1, totalTokens: 2 },
-          },
-        }),
-      ],
-      live: [
-        live({
-          id: "a1",
-          role: "assistant",
-          parts: [{ type: "text", text: "reply" }],
-          metadata: {
-            usage: { inputTokens: 100, outputTokens: 50, totalTokens: 150 },
-          },
-        }),
-      ],
-      isStreaming: false,
-      t,
-    });
-    // The live (authoritative, freshest) usage wins, not the stale row usage.
-    expect(md).toContain("- Total tokens: 150");
-    expect(md).not.toContain("- Total tokens: 2");
-  });
-
-  it("a current-turn live message with no matching row renders without a footer", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [row({ id: "u1", role: "user", content: "q" })],
-      live: [
-        live({ id: "u1", role: "user", parts: [{ type: "text", text: "q" }] }),
-        live({
-          id: "a-live",
-          role: "assistant",
-          parts: [{ type: "text", text: "fresh reply" }],
-        }),
-      ],
-      isStreaming: false,
-      t,
-    });
-    expect(md).toContain("fresh reply");
-    // No persisted row for the live assistant -> no token footer, no timestamp.
-    expect(md).not.toContain("_Tokens —");
-    expect(md).not.toContain("<!-- undefined -->");
-  });
-});
-
-describe("buildChatMarkdown — fallback + banner", () => {
-  it("falls back to the persisted rows when there are no live messages", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [
-        row({ role: "user", content: "from rows" }),
-        row({
-          role: "assistant",
-          content: "answer",
-          metadata: { usage: { inputTokens: 4, outputTokens: 6 } },
-        }),
-      ],
-      live: [], // empty live mirror -> fallback path
-      isStreaming: false,
-      t,
-    });
-    expect(md).toContain("## 1. You");
-    expect(md).toContain("## 2. AI agent");
-    expect(md).toContain("from rows");
-    expect(md).toContain("- Messages: 2");
-    expect(md).toContain("- Total tokens: 10");
-  });
-
-  it("appends the on-screen banner once, after the messages", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [row({ role: "user", content: "q" })],
-      live: [
-        live({ id: "u", role: "user", parts: [{ type: "text", text: "q" }] }),
-      ],
-      isStreaming: false,
-      banner: "Rate limit reached — try again shortly.",
-      t,
-    });
-    expect(md).toContain("_⚠️ Rate limit reached — try again shortly._");
-    // Banner comes after the (only) message block.
-    expect(md.indexOf("Rate limit reached")).toBeGreaterThan(
-      md.indexOf("## 1."),
-    );
-  });
-
-  it("omits the banner block when there is no banner", () => {
-    const md = buildChatMarkdown({
-      title: "t",
-      chatId: "c",
-      rows: [row({ role: "user", content: "q" })],
-      live: [
-        live({ id: "u", role: "user", parts: [{ type: "text", text: "q" }] }),
-      ],
-      isStreaming: false,
-      banner: null,
-      t,
-    });
-    expect(md).not.toContain("_⚠️");
-  });
-});
-
-// #174: a brand-new, not-yet-persisted chat whose first turn is streaming (or was
-// interrupted) has live messages but NO persisted rows yet, and its chat id is not
-// known (the caller passes a placeholder). The export must still capture the
-// on-screen thread WYSIWYG from the live messages alone.
-describe("buildChatMarkdown — first-turn export with no persisted base (#174)", () => {
-  it("builds the document from live messages alone when rows are empty", () => {
-    const md = buildChatMarkdown({
-      title: null,
-      chatId: "unsaved",
-      rows: [],
-      live: [
-        live({
-          id: "u1",
-          role: "user",
-          parts: [{ type: "text", text: "hello" }],
-        }),
-        live({
-          id: "a1",
-          role: "assistant",
-          parts: [{ type: "text", text: "partial reply" }],
-        }),
-      ],
-      isStreaming: true,
-      t,
-    });
-    // Both on-screen messages are serialized, numbered from 1.
-    expect(md).toContain("## 1. You");
-    expect(md).toContain("hello");
-    expect(md).toContain("## 2. AI agent");
-    expect(md).toContain("partial reply");
-    // The streaming tail assistant is flagged as in-progress.
-    expect(md).toContain("still being generated");
-    // The placeholder chat id and the live message count are recorded.
-    expect(md).toContain("- Chat ID: `unsaved`");
-    expect(md).toContain("- Messages: 2");
-    // No persisted timestamp exists for a current-turn live message.
-    expect(md).not.toContain("<!--");
-  });
-
-  it("captures an interrupted first turn (no rows, not streaming) without a generating note", () => {
-    const md = buildChatMarkdown({
-      title: null,
-      chatId: "unsaved",
-      rows: [],
-      live: [
-        live({ id: "u1", role: "user", parts: [{ type: "text", text: "q" }] }),
-        live({
-          id: "a1",
-          role: "assistant",
-          parts: [{ type: "text", text: "half an answer" }],
-        }),
-      ],
-      isStreaming: false,
-      banner: "Connection dropped — the response was cut off.",
-      t,
-    });
-    expect(md).toContain("half an answer");
-    // An interrupted (non-streaming) partial is exported as-is, no generating note.
-    expect(md).not.toContain("still being generated");
-    // The on-screen banner records the interruption.
-    expect(md).toContain("_⚠️ Connection dropped — the response was cut off._");
-  });
-});

apps/client/src/features/ai-chat/utils/chat-markdown.ts

@@ -1,308 +0,0 @@
-/**
- * Client-only Markdown builder for an AI agent chat. Serializes the already
- * persisted message rows (loaded via `useAiChatMessagesQuery`) into a single
- * Markdown string suitable for copying to the clipboard. NO network call is
- * made and NO server/DB code is touched — this reuses the rich "request
- * internals" (tool calls with input/output, per-message token usage,
- * finish/error info) that the chat already holds client-side.
- *
- * Only role labels and tool action labels are localized via the passed-in `t`
- * translator; the structural document words (Input/Output/Error/Tokens/...) are
- * plain English constants because the output is a technical artifact.
- */
-
-import type { IAiChatMessageRow } from "@/features/ai-chat/types/ai-chat.types.ts";
-import {
-  ToolUiPart,
-  getToolName,
-  toolRunState,
-  toolLabelKey,
-} from "@/features/ai-chat/utils/tool-parts.tsx";
-
-// Minimal translator signature compatible with react-i18next's `t`.
-type Translate = (key: string, values?: Record<string, unknown>) => string;
-
-interface BuildChatMarkdownArgs {
-  title: string | null;
-  chatId: string;
-  /** The live, on-screen messages — the WYSIWYG source of the export. When
-   *  present and non-empty these DRIVE the document (so it mirrors exactly what
-   *  the user sees, including a partial reply from an interrupted turn). Each is
-   *  matched to a persisted row by `id` to enrich it with token usage / error /
-   *  timestamp. When absent or empty the builder falls back to `rows`. */
-  live?: LiveMessage[];
-  /** Persisted message rows. Enrichment source (matched to `live` by id) AND the
-   *  fallback document source when `live` is empty. */
-  rows: IAiChatMessageRow[];
-  /** Whether the live thread is still streaming. Only then is the tail assistant
-   *  message flagged "still generating"; an interrupted (non-streaming) partial
-   *  reply is exported as-is and the `banner` explains the interruption. */
-  isStreaming?: boolean;
-  /** The on-screen banner text (error / dropped connection / manual stop),
-   *  appended at the end of the export so the artifact records the interruption
-   *  the user saw. */
-  banner?: string | null;
-  t: Translate;
-}
-
-/** A single AI SDK UIMessage part (text part or other). */
-interface TextLikePart {
-  type: string;
-  text?: string;
-}
-
-/** Authoritative per-turn usage the server attaches to a message / row. */
-interface UsageLike {
-  inputTokens?: number;
-  outputTokens?: number;
-  totalTokens?: number;
-  reasoningTokens?: number;
-}
-
-/** A live, on-screen message (subset of the AI SDK UIMessage we consume). */
-interface LiveMessage {
-  id: string;
-  role: "user" | "assistant" | string;
-  parts: TextLikePart[];
-  metadata?: { usage?: UsageLike; error?: string };
-}
-
-/** One message normalized for rendering, regardless of live/persisted origin. */
-interface ExportItem {
-  role: string;
-  parts: TextLikePart[];
-  usage?: UsageLike;
-  error?: string;
-  /** ISO timestamp from the persisted row, when one is known. */
-  createdAt?: string;
-  /** True only for the tail assistant message while the thread is streaming. */
-  generating: boolean;
-}
-
-/**
- * Stringify an arbitrary tool input/output value for a fenced block. Strings
- * pass through as-is; everything else is pretty-printed JSON, falling back to
- * `String(value)` if serialization throws (e.g. a circular structure).
- */
-function stringify(value: unknown): string {
-  if (typeof value === "string") return value;
-  try {
-    return JSON.stringify(value, null, 2);
-  } catch {
-    return String(value);
-  }
-}
-
-/**
- * Wrap `code` in a fenced code block whose backtick delimiter is LONGER than
- * the longest backtick run inside the content, so embedded backticks (or even
- * a literal ``` fence) never break out of the block. Minimum 3 backticks.
- */
-function fence(code: string, lang = ""): string {
-  const runs: string[] = code.match(/`+/g) ?? [];
-  const longest = runs.reduce((m, s) => Math.max(m, s.length), 0);
-  const delim = "`".repeat(Math.max(3, longest + 1));
-  return `${delim}${lang}\n${code}\n${delim}`;
-}
-
-/** Per-row token count, mirroring the header sum in ai-chat-window.tsx. */
-function rowTokens(usage: {
-  inputTokens?: number;
-  outputTokens?: number;
-  totalTokens?: number;
-  reasoningTokens?: number;
-}): number {
-  return (
-    usage.totalTokens ?? (usage.inputTokens ?? 0) + (usage.outputTokens ?? 0)
-  );
-}
-
-/** Render one message's UIMessage parts into an array of Markdown blocks
- *  (text blocks + tool blocks). Mirrors MessageItem's part handling. */
-function renderMessageParts(parts: TextLikePart[], t: Translate): string[] {
-  const out: string[] = [];
-
-  for (const part of parts) {
-    if (part.type === "text") {
-      const text = (part.text ?? "").trim();
-      // Skip empty/whitespace-only text parts (matches MessageItem).
-      if (text.length > 0) out.push(text);
-      continue;
-    }
-
-    const isToolPart =
-      part.type.startsWith("tool-") || part.type === "dynamic-tool";
-    if (!isToolPart) continue;
-
-    const tp = part as unknown as ToolUiPart;
-    const name = getToolName(tp);
-    const { key, values } = toolLabelKey(name);
-    const label = t(key, values);
-    const state = toolRunState(tp.state);
-
-    const toolLines: string[] = [
-      `**Tool: ${label}** (\`${name}\`) — ${state}`,
-    ];
-    if (tp.input !== undefined) {
-      toolLines.push("Input:");
-      toolLines.push(fence(stringify(tp.input), "json"));
-    }
-    if (tp.output !== undefined) {
-      toolLines.push("Output:");
-      toolLines.push(fence(stringify(tp.output), "json"));
-    }
-    if (tp.errorText) {
-      toolLines.push(`**Error:** ${tp.errorText}`);
-    }
-    out.push(toolLines.join("\n\n"));
-  }
-
-  return out;
-}
-
-/** Resolve a persisted row's parts: prefer the rich persisted parts, else a
- *  single text part built from the plain-text content (mirrors `rowToUiMessage`). */
-function rowParts(row: IAiChatMessageRow): TextLikePart[] {
-  return Array.isArray(row.metadata?.parts) && row.metadata.parts.length > 0
-    ? (row.metadata.parts as TextLikePart[])
-    : [{ type: "text", text: row.content ?? "" }];
-}
-
-/**
- * Normalize the export to one ordered list of {@link ExportItem}, WYSIWYG-first:
- *
- * - When `live` messages are present, THEY are the document (what the user sees,
- *   incl. an interrupted turn's partial reply). Each is matched to a persisted
- *   row by `id` to pull token usage / error / timestamp — a live message of the
- *   CURRENT turn has no matching row yet, so it simply renders without a footer.
- *   Authoritative `usage`/`error` already on the live message metadata win over
- *   the row (the server attaches usage to the streamed message at a step
- *   boundary before the row is refetched). Only the tail assistant message is
- *   flagged `generating`, and only while `isStreaming`.
- * - When `live` is empty (e.g. the export runs before the live mirror is
- *   populated), fall back to the persisted `rows` so the format never regresses.
- */
-function resolveItems(
-  live: LiveMessage[] | undefined,
-  rows: IAiChatMessageRow[],
-  isStreaming: boolean,
-): ExportItem[] {
-  if (live && live.length > 0) {
-    const rowsById = new Map(rows.map((r) => [r.id, r]));
-    // The "still generating" note may apply ONLY to an assistant message that is
-    // the actual TAIL of the list — that is where the on-screen typing indicator
-    // sits. While `status === "submitted"` (isStreaming true) right after the
-    // user hit send, the tail is the USER message and the new assistant turn has
-    // no message yet; the previous assistant answer is shown complete on screen,
-    // so it must NOT be flagged (the indicator renders as a separate bottom
-    // block, not on that answer).
-    const lastIndex = live.length - 1;
-    const tailIsStreamingAssistant =
-      isStreaming && live[lastIndex]?.role === "assistant";
-    return live.map((m, i) => {
-      const row = rowsById.get(m.id);
-      return {
-        role: m.role,
-        parts: m.parts ?? [],
-        // Authoritative usage/error already on the live message (the server
-        // attaches usage to the streamed message at a step boundary) wins over
-        // the persisted row; a current-turn live message has no matching row yet
-        // and simply renders without a token footer (the accepted WYSIWYG
-        // tradeoff — an interrupted turn loses only its token footer, not text).
-        usage: m.metadata?.usage ?? row?.metadata?.usage,
-        error: m.metadata?.error ?? row?.metadata?.error ?? undefined,
-        createdAt: row?.createdAt,
-        generating: tailIsStreamingAssistant && i === lastIndex,
-      };
-    });
-  }
-
-  return rows.map((row) => ({
-    role: row.role,
-    parts: rowParts(row),
-    usage: row.metadata?.usage,
-    error: row.metadata?.error ?? undefined,
-    createdAt: row.createdAt,
-    generating: false,
-  }));
-}
-
-/**
- * Serialize a chat to a Markdown string. Pure (apart from `new Date()` for the
- * export timestamp), so it is straightforward to unit-test.
- */
-export function buildChatMarkdown(args: BuildChatMarkdownArgs): string {
-  const { title, chatId, live, rows, isStreaming, banner, t } = args;
-  const blocks: string[] = [];
-
-  const items = resolveItems(live, rows, isStreaming === true);
-
-  const heading = (title ?? "").trim() || t("Untitled chat");
-  blocks.push(`# ${heading}`);
-
-  // Metadata bullet list. Total tokens is only shown when there is a sum.
-  const totalTokens = items.reduce(
-    (sum, item) => (item.usage ? sum + rowTokens(item.usage) : sum),
-    0,
-  );
-  const meta = [
-    `- Chat ID: \`${chatId}\``,
-    `- Exported: ${new Date().toISOString()}`,
-    `- Messages: ${items.length}`,
-  ];
-  if (totalTokens > 0) meta.push(`- Total tokens: ${totalTokens}`);
-  blocks.push(meta.join("\n"));
-
-  items.forEach((item, index) => {
-    blocks.push("---");
-
-    const roleLabel = item.role === "assistant" ? t("AI agent") : t("You");
-    blocks.push(`## ${index + 1}. ${roleLabel}`);
-
-    // Created-at kept in source as an HTML comment (out of the rendered prose).
-    // A live message of the current turn has no persisted row yet — omit it.
-    if (item.createdAt) blocks.push(`<!-- ${item.createdAt} -->`);
-
-    blocks.push(...renderMessageParts(item.parts, t));
-
-    // A generating assistant may have empty/no parts yet — the heading (above)
-    // and this note still record the in-progress turn.
-    if (item.generating) {
-      blocks.push(
-        "_⏳ This message is still being generated — the export captured a partial, in-progress response._",
-      );
-    }
-
-    // A persisted per-message error (the raw provider text) may coexist with the
-    // trailing `banner` (the classified on-screen alert) when the failed turn's
-    // row has already been refetched by export time. They describe the same
-    // failure at different fidelity; showing both is an accepted, minor redundancy.
-    if (item.error) {
-      blocks.push(`**⚠️ Error:** ${item.error}`);
-    }
-
-    const usage = item.usage;
-    if (usage) {
-      const total = usage.totalTokens ?? rowTokens(usage);
-      // Reasoning (thinking) tokens are shown only when the provider reported a
-      // positive count; old rows / non-reasoning providers omit it.
-      const reasoning =
-        usage.reasoningTokens && usage.reasoningTokens > 0
-          ? `, reasoning: ${usage.reasoningTokens}`
-          : "";
-      blocks.push(
-        `_Tokens — in: ${usage.inputTokens ?? "?"}, out: ${usage.outputTokens ?? "?"}${reasoning}, total: ${total}_`,
-      );
-    }
-  });
-
-  // Record the on-screen banner (error / dropped connection / manual stop) so
-  // the export reflects exactly what the user saw, including an interruption.
-  if (banner && banner.trim().length > 0) {
-    blocks.push("---");
-    blocks.push(`_⚠️ ${banner.trim()}_`);
-  }
-
-  // Blank line between blocks so the Markdown renders cleanly.
-  return blocks.join("\n\n");
-}

apps/client/src/features/ai-chat/utils/collapse-blank-lines.test.ts

@@ -0,0 +1,61 @@
+import { describe, it, expect } from "vitest";
+import { collapseBlankLines } from "@/features/ai-chat/utils/collapse-blank-lines.ts";
+import { renderChatMarkdown } from "@/features/ai-chat/utils/markdown.ts";
+
+describe("collapseBlankLines", () => {
+  it("collapses a run of 2+ newlines to a single newline", () => {
+    expect(collapseBlankLines("a\n\nb")).toBe("a\nb");
+    expect(collapseBlankLines("a\n\n\n\nb")).toBe("a\nb");
+  });
+
+  it("keeps single newlines untouched", () => {
+    expect(collapseBlankLines("a\nb\nc")).toBe("a\nb\nc");
+  });
+
+  it("preserves blank lines INSIDE a fenced code block", () => {
+    const src = "a\n\n\nb\n\n```\nx\n\n\ny\n```\n\nc";
+    // Prose blanks collapse; the blank lines between the ``` fences survive.
+    expect(collapseBlankLines(src)).toBe("a\nb\n```\nx\n\n\ny\n```\nc");
+  });
+
+  it("handles a tilde fence and preserves its interior blanks", () => {
+    const src = "p\n\n~~~\ncode\n\nmore\n~~~\n\nq";
+    expect(collapseBlankLines(src)).toBe("p\n~~~\ncode\n\nmore\n~~~\nq");
+  });
+
+  it("leaves an unclosed fence's remaining lines verbatim", () => {
+    const src = "intro\n\n```\nstill\n\nopen";
+    expect(collapseBlankLines(src)).toBe("intro\n```\nstill\n\nopen");
+  });
+
+  it("is a no-op for text with no blank lines", () => {
+    expect(collapseBlankLines("just one line")).toBe("just one line");
+  });
+});
+
+describe("collapseBlankLines + renderChatMarkdown (tight reasoning rendering)", () => {
+  it("renders a blank-line-separated list as a TIGHT list (no <li><p>)", () => {
+    const loose =
+      "Intro paragraph.\n\n- item one\n\n- item two\n\n- item three";
+    const html = renderChatMarkdown(collapseBlankLines(loose), {});
+    // Tight list: each <li> holds the text directly, not wrapped in a <p>.
+    expect(html).toContain("<li>item one</li>");
+    expect(html).not.toContain("<li><p>");
+    // The list still parses as a list after the paragraph (not a paragraph+<br>).
+    expect(html).toContain("<ul>");
+    expect(html).toContain("<p>Intro paragraph.</p>");
+  });
+
+  it("renders an ordered list (1. 2.) as tight after collapsing", () => {
+    const loose = "Intro.\n\n1. first\n\n2. second";
+    const html = renderChatMarkdown(collapseBlankLines(loose), {});
+    expect(html).toContain("<ol>");
+    expect(html).toContain("<li>first</li>");
+    expect(html).not.toContain("<li><p>");
+  });
+
+  it("the loose source WOULD render <li><p> without collapsing (control)", () => {
+    const loose = "- a\n\n- b";
+    expect(renderChatMarkdown(loose, {})).toContain("<li><p>");
+  });
+});

apps/client/src/features/ai-chat/utils/collapse-blank-lines.ts

@@ -0,0 +1,56 @@
+// Pure helper for compact reasoning ("Thinking") rendering. Kept free of React
+// so it can be unit-tested in isolation (see collapse-blank-lines.test.ts).
+
+/**
+ * Collapse runs of 2+ newlines down to a single newline, EXCEPT inside fenced
+ * code blocks (``` ... ``` or ~~~ ... ~~~), where blank lines are significant.
+ *
+ * Why: reasoning models emit thinking with a blank line (`\n\n`) between every
+ * list item and paragraph. `marked` turns those into "loose" lists (each `<li>`
+ * wrapped in a `<p>`) and separate `<p>` paragraphs, each carrying a vertical
+ * margin — so the "Thinking" block renders with large, airy gaps. Removing the
+ * blank-line gaps yields tight lists (no `<li><p>`) and joined paragraphs. The
+ * chat markdown renderer runs with `breaks: true`, so a single `\n` still
+ * becomes a `<br>` — line breaks inside the reasoning are preserved; only the
+ * empty gaps between blocks disappear. Apply ONLY to reasoning text, never to a
+ * normal assistant answer (where paragraph spacing is intentional).
+ *
+ * Fenced code is preserved verbatim: a fence opens on a line whose first
+ * non-space characters are ``` or ~~~ and closes on the next line that starts
+ * with the same fence character. Blank lines between fences (significant for
+ * code formatting) are never collapsed.
+ */
+export function collapseBlankLines(text: string): string {
+  const lines = text.split("\n");
+  const out: string[] = [];
+  let inFence = false;
+  let fenceChar = "";
+
+  for (const line of lines) {
+    const fenceMatch = line.match(/^\s*(`{3,}|~{3,})/);
+    if (fenceMatch) {
+      const ch = fenceMatch[1][0];
+      if (!inFence) {
+        inFence = true;
+        fenceChar = ch;
+      } else if (ch === fenceChar) {
+        inFence = false;
+      }
+      out.push(line);
+      continue;
+    }
+
+    // Inside a fenced block every line (including blanks) is significant.
+    if (inFence) {
+      out.push(line);
+      continue;
+    }
+
+    // Outside fences: drop blank lines so a `\n\n+` gap collapses to a single
+    // `\n` between the surrounding content lines.
+    if (line.trim() === "") continue;
+    out.push(line);
+  }
+
+  return out.join("\n");
+}

apps/client/src/features/ai-chat/utils/count-stream-tokens.test.ts

@@ -117,3 +117,55 @@ describe("liveTurnTokens — authoritative path", () => {
     expect(r).toEqual({ reasoning: 0, output: 1, authoritative: false });
   });
 });
+
+describe("liveTurnTokens — combined authoritative + estimate (#163)", () => {
+  it("ticks the in-flight step above the completed-steps authoritative base", () => {
+    // The authoritative usage is the sum over COMPLETED steps (step 1). The
+    // CURRENT step is streaming and its text is NOT in `usage` yet, but it IS in
+    // the parts -> the running estimate must push the live figure above the base
+    // so the badge keeps growing between step boundaries.
+    const longText = "x".repeat(800); // 800 chars -> 200 est output tokens
+    const r = liveTurnTokens(
+      msg([{ type: "text", text: longText }], {
+        usage: { inputTokens: 500, outputTokens: 40 }, // step-1 base: 40 output
+      }),
+    );
+    // max(authOutput=40, estOutput=200) = 200 -> the counter ticks, not frozen.
+    expect(r.output).toBe(200);
+    expect(r.authoritative).toBe(true);
+  });
+
+  it("ticks reasoning of the in-flight step above the authoritative reasoning base", () => {
+    const longReasoning = "r".repeat(400); // 400 chars -> 100 est reasoning
+    const r = liveTurnTokens(
+      msg([{ type: "reasoning", text: longReasoning }], {
+        usage: { inputTokens: 100, outputTokens: 20, reasoningTokens: 20 },
+      }),
+    );
+    // reasoning: max(20, 100) = 100 ; output: max(max(0,20-20)=0, 0) = 0.
+    expect(r.reasoning).toBe(100);
+    expect(r.output).toBe(0);
+    expect(r.authoritative).toBe(true);
+  });
+
+  it("snaps to the authoritative figure once it exceeds the rough estimate", () => {
+    // Short on-screen text (estimate tiny) but a large authoritative output:
+    // the exact figure wins at the boundary (the counter never under-reports).
+    const r = liveTurnTokens(
+      msg([{ type: "text", text: "abcd" }], {
+        usage: { inputTokens: 10, outputTokens: 5000 },
+      }),
+    );
+    expect(r.output).toBe(5000);
+  });
+
+  it("is monotonic: max never drops below the authoritative base when the estimate is smaller", () => {
+    // Mirrors the legacy 'verbatim' tests: estimate < authoritative -> unchanged.
+    const r = liveTurnTokens(
+      msg([{ type: "text", text: "tiny" }], {
+        usage: { inputTokens: 500, outputTokens: 100, reasoningTokens: 30 },
+      }),
+    );
+    expect(r).toEqual({ reasoning: 30, output: 70, authoritative: true });
+  });
+});

apps/client/src/features/ai-chat/utils/count-stream-tokens.ts

@@ -56,39 +56,58 @@ function metadataUsage(message: UIMessage): AuthoritativeUsage | undefined {
 /**
  * Token split for the given (streaming) assistant message.
  *
- * Prefers AUTHORITATIVE `metadata.usage` when the server has attached it (at a
- * step/turn boundary, incl. `reasoningTokens`) — so the live counter snaps to the
- * provider's exact figures. Until then it returns a running ESTIMATE summed over
- * the message parts: `reasoning` parts feed the reasoning estimate, `text` parts
- * feed the output estimate. Multi-part / multi-step turns accumulate naturally
- * because every part of the turn is summed.
+ * COMBINES the authoritative server usage with the running text estimate so the
+ * counter ticks in real time AND lands exact. The server only attaches
+ * `metadata.usage` at a step/turn boundary (`finish-step`/`finish`) and it is
+ * CUMULATIVE over COMPLETED steps — it does NOT yet include the in-flight step.
+ * So a multi-step turn that returned the authoritative figure verbatim would
+ * FREEZE between boundaries and jump in steps (issue #163).
+ *
+ * Instead we always compute the running ESTIMATE (chars/≈4 over the message's
+ * `reasoning`/`text` parts, which grows on every streamed delta) and take the
+ * per-component MAX of the authoritative base and the estimate:
+ *   - between boundaries the estimate of the in-flight step ticks the number up;
+ *   - at a boundary the authoritative figure snaps it to exact;
+ *   - because the server's usage is cumulative and we only ever take the max, the
+ *     number is MONOTONIC — it never drops.
  *
  * Providers that don't stream reasoning text still surface a reasoning count once
- * the authoritative usage arrives (`usage.reasoningTokens`); on the pure estimate
- * path such a turn simply shows `reasoning: 0` until then.
+ * the authoritative usage arrives (`max(reasoningTokens, 0)`); on the pure
+ * estimate path (no usage yet) such a turn shows `reasoning: 0` until then.
  */
 export function liveTurnTokens(message: UIMessage | undefined): LiveTurnTokens {
   if (!message) return { reasoning: 0, output: 0, authoritative: false };
 
-  const usage = metadataUsage(message);
-  if (usage) {
-    // Authoritative branch: outputTokens already INCLUDES reasoning tokens in the
-    // AI SDK usage shape, so subtract reasoning out for the "answer" figure (never
-    // go negative if a provider reports them inconsistently).
-    const reasoning = usage.reasoningTokens ?? 0;
-    const totalOutput = usage.outputTokens ?? 0;
-    const output = Math.max(0, totalOutput - reasoning);
-    return { reasoning, output, authoritative: true };
-  }
-
-  let reasoning = 0;
-  let output = 0;
+  // Running ESTIMATE over every reasoning/text part — grows on each delta. This
+  // includes the IN-FLIGHT step, which the authoritative usage does not cover yet.
+  let estReasoning = 0;
+  let estOutput = 0;
   for (const part of message.parts ?? []) {
     if (part.type === "reasoning") {
-      reasoning += estimateTokens((part as { text?: string }).text ?? "");
+      estReasoning += estimateTokens((part as { text?: string }).text ?? "");
     } else if (part.type === "text") {
-      output += estimateTokens((part as { text?: string }).text ?? "");
+      estOutput += estimateTokens((part as { text?: string }).text ?? "");
     }
   }
-  return { reasoning, output, authoritative: false };
+
+  const usage = metadataUsage(message);
+  if (!usage) {
+    // No authoritative usage streamed yet: the estimate IS the live figure.
+    return { reasoning: estReasoning, output: estOutput, authoritative: false };
+  }
+
+  // Authoritative sum over COMPLETED steps. `outputTokens` already INCLUDES
+  // reasoning in the AI SDK usage shape, so subtract it out for the "answer"
+  // figure (never go negative if a provider reports them inconsistently).
+  const authReasoning = usage.reasoningTokens ?? 0;
+  const authOutput = Math.max(0, (usage.outputTokens ?? 0) - authReasoning);
+
+  // Per-component max: the in-flight step's estimate ticks above the completed-
+  // steps base between boundaries, and the authoritative figure wins once it
+  // exceeds the (rough) estimate at the next boundary. Monotonic by construction.
+  return {
+    reasoning: Math.max(authReasoning, estReasoning),
+    output: Math.max(authOutput, estOutput),
+    authoritative: true,
+  };
 }

apps/client/src/features/ai-chat/utils/message-signature.test.ts

@@ -0,0 +1,241 @@
+import { describe, expect, it } from "vitest";
+import type { UIMessage } from "@ai-sdk/react";
+import { messageSignature } from "@/features/ai-chat/utils/message-signature.ts";
+
+/**
+ * Pure-helper tests for `messageSignature`, the cheap per-message content
+ * signature that drives MessageItem's memo (a streaming row's signature must
+ * change on every delta so it re-renders, while a finalized row's stays stable
+ * so it is skipped). Each test exercises ONE change signal and asserts it flips
+ * the signature; a content-identical clone must keep an EQUAL signature.
+ *
+ * The signature embeds `message.id` and `message.role`, so the `msg` factory
+ * uses a FIXED id/role here (not `Math.random()`): otherwise two messages with
+ * identical content would get different signatures and the negative case would
+ * be impossible to express.
+ */
+const msg = (
+  parts: UIMessage["parts"],
+  metadata?: unknown,
+): UIMessage =>
+  ({
+    id: "m1",
+    role: "assistant",
+    parts,
+    metadata,
+  }) as UIMessage;
+
+describe("messageSignature", () => {
+  it("changes when a text part grows", () => {
+    const before = msg([{ type: "text", text: "alpha" }]);
+    const after = msg([{ type: "text", text: "alpha beta" }]);
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("changes when a new part is appended", () => {
+    const before = msg([{ type: "text", text: "alpha" }]);
+    const after = msg([
+      { type: "text", text: "alpha" },
+      { type: "text", text: "beta" },
+    ]);
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("changes when a part's state flips", () => {
+    const before = msg([
+      { type: "tool-getPage", state: "input-streaming" } as never,
+    ]);
+    const after = msg([
+      { type: "tool-getPage", state: "output-available" } as never,
+    ]);
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("changes when a tool part gains an output", () => {
+    const before = msg([
+      { type: "tool-getPage", state: "output-available" } as never,
+    ]);
+    const after = msg([
+      {
+        type: "tool-getPage",
+        state: "output-available",
+        output: { ok: true },
+      } as never,
+    ]);
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("changes when a part gains an errorText", () => {
+    const before = msg([
+      { type: "tool-getPage", state: "output-error" } as never,
+    ]);
+    const after = msg([
+      {
+        type: "tool-getPage",
+        state: "output-error",
+        errorText: "boom",
+      } as never,
+    ]);
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("changes when usage.reasoningTokens arrives on finish-step (text/state already frozen)", () => {
+    // The specifically-commented edge case: the authoritative turn total lands on
+    // the final finish-step AFTER the reasoning text length and state are frozen.
+    // Only the token count appears between these two snapshots, so the signature
+    // MUST still flip — otherwise the "Thinking · N tokens" header would never
+    // snap from the live estimate to the exact figure.
+    const before = msg([
+      { type: "reasoning", text: "thinking", state: "done" } as never,
+    ]);
+    const after = msg(
+      [{ type: "reasoning", text: "thinking", state: "done" } as never],
+      { usage: { reasoningTokens: 42 } },
+    );
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("changes when metadata.error appears", () => {
+    const before = msg([{ type: "text", text: "answer" }]);
+    const after = msg([{ type: "text", text: "answer" }], { error: "boom" });
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("changes when metadata.finishReason changes (e.g. to 'aborted')", () => {
+    const before = msg([{ type: "text", text: "answer" }], {
+      finishReason: "stop",
+    });
+    const after = msg([{ type: "text", text: "answer" }], {
+      finishReason: "aborted",
+    });
+    expect(messageSignature(before)).not.toBe(messageSignature(after));
+  });
+
+  it("is UNCHANGED for a content-identical clone (different object, same values)", () => {
+    // A finalized row that is re-created as a fresh object (different parts array
+    // by reference, same parts by value) must keep an EQUAL signature, so the
+    // memo skips re-rendering it.
+    const a = msg([
+      { type: "text", text: "alpha" },
+      { type: "tool-getPage", state: "output-available", output: { ok: true } } as never,
+    ]);
+    const b = msg([
+      { type: "text", text: "alpha" },
+      { type: "tool-getPage", state: "output-available", output: { ok: true } } as never,
+    ]);
+    expect(a).not.toBe(b);
+    expect(messageSignature(a)).toBe(messageSignature(b));
+  });
+});
+
+/**
+ * Per-part-kind coupling guard for the load-bearing invariant documented at the
+ * top of message-signature.ts: the signature MUST sample every VISIBLE field the
+ * MessageItem render body draws, or the memo freezes a stale row. This is an
+ * executable lock for the part kinds rendered TODAY — read alongside
+ * `MessageItem` (message-item.tsx) and the `assistantMessageHasVisibleContent`
+ * helper (message-content.ts), which "mirrors MessageItem's render decisions
+ * EXACTLY". For each kind, mutating a field the render body DRAWS must flip the
+ * signature. If a new visible field is rendered without being added here AND to
+ * the signature, the corresponding assertion below should fail — that is the
+ * guard. (This intentionally stops short of the render-descriptor refactor:
+ * adding a part kind or a visible field still requires a human to extend both
+ * the signature and this block.)
+ */
+describe("messageSignature ↔ render coupling (per visible part kind)", () => {
+  describe("text part — render draws part.text (MarkdownPart text={part.text})", () => {
+    it("flips when the visible text changes", () => {
+      // Streaming is append-only, so the visible text only grows; the signature
+      // samples its length, so the growth is the change signal.
+      const before = msg([{ type: "text", text: "answer" }]);
+      const after = msg([{ type: "text", text: "answer extended" }]);
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+  });
+
+  describe("reasoning part — render draws text + tokens (ReasoningBlock)", () => {
+    it("flips when the visible reasoning text changes", () => {
+      const before = msg([
+        { type: "reasoning", text: "think", state: "streaming" } as never,
+      ]);
+      const after = msg([
+        { type: "reasoning", text: "think harder", state: "streaming" } as never,
+      ]);
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+
+    it("flips when the visible token count (metadata.usage.reasoningTokens) lands", () => {
+      // The header's "Thinking · N tokens" reads reasoningTokensForPart, fed by
+      // metadata.usage.reasoningTokens — a VISIBLE field that arrives on the final
+      // finish-step after text length and state are frozen.
+      const before = msg([
+        { type: "reasoning", text: "think", state: "done" } as never,
+      ]);
+      const after = msg(
+        [{ type: "reasoning", text: "think", state: "done" } as never],
+        { usage: { reasoningTokens: 99 } },
+      );
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+  });
+
+  describe("tool-* part — render draws state/errorText/citations (ToolCallCard)", () => {
+    it("flips when the run state changes (running ↔ done icon + label)", () => {
+      // toolRunState(part.state) selects the spinner/check/error icon.
+      const before = msg([
+        { type: "tool-getPage", state: "input-available" } as never,
+      ]);
+      const after = msg([
+        { type: "tool-getPage", state: "output-available" } as never,
+      ]);
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+
+    it("flips when output arrives (drives the rendered citation links)", () => {
+      // toolCitations reads part.output to render the "/p/{id}" anchors.
+      const before = msg([
+        { type: "tool-getPage", state: "output-available" } as never,
+      ]);
+      const after = msg([
+        {
+          type: "tool-getPage",
+          state: "output-available",
+          output: { id: "page-1", title: "Doc" },
+        } as never,
+      ]);
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+
+    it("flips when errorText appears (the visible red error detail line)", () => {
+      const before = msg([
+        { type: "tool-getPage", state: "output-error" } as never,
+      ]);
+      const after = msg([
+        {
+          type: "tool-getPage",
+          state: "output-error",
+          errorText: "permission denied",
+        } as never,
+      ]);
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+  });
+
+  describe("metadata banners — render draws error / aborted notices", () => {
+    it("flips when metadata.error appears (ChatErrorAlert banner)", () => {
+      const before = msg([{ type: "text", text: "answer" }]);
+      const after = msg([{ type: "text", text: "answer" }], { error: "boom" });
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+
+    it("flips when metadata.finishReason becomes 'aborted' (ChatStoppedNotice)", () => {
+      const before = msg([{ type: "text", text: "answer" }], {
+        finishReason: "stop",
+      });
+      const after = msg([{ type: "text", text: "answer" }], {
+        finishReason: "aborted",
+      });
+      expect(messageSignature(before)).not.toBe(messageSignature(after));
+    });
+  });
+});

apps/client/src/features/ai-chat/utils/message-signature.ts

@@ -0,0 +1,44 @@
+import type { UIMessage } from "@ai-sdk/react";
+
+/** Cheap content signature for one message: changes iff something VISIBLE in the
+ *  row changed. Streaming is APPEND-ONLY (text parts only grow, parts are only
+ *  appended, a tool/text part flips state once), so a per-part [type, text
+ *  length, state, error/output presence] tuple + the persisted metadata
+ *  (error/finishReason) is a sufficient change signal without comparing full
+ *  strings on every delta. WARNING — load-bearing for the MessageItem memo:
+ *  if a future part kind's VISIBLE content can change WITHOUT changing [type,
+ *  text length, state, error/output presence] (e.g. a tool that streams
+ *  `preliminary` output, or a client-side regenerate that edits a finalized
+ *  row in place), extend this signature or the memo will freeze a stale row. */
+export function messageSignature(message: UIMessage): string {
+  const parts = message.parts
+    .map((p) => {
+      const any = p as {
+        type: string;
+        text?: string;
+        state?: string;
+        errorText?: string;
+        output?: unknown;
+      };
+      return [
+        any.type,
+        any.text?.length ?? 0,
+        any.state ?? "",
+        any.errorText ? 1 : 0,
+        any.output !== undefined ? 1 : 0,
+      ].join(":");
+    })
+    .join("|");
+  const meta = message.metadata as
+    | { error?: string; finishReason?: string; usage?: { reasoningTokens?: number } }
+    | undefined;
+  // `usage.reasoningTokens` is neither append-only nor part-bound: the authoritative
+  // turn total arrives on the final `finish-step` AFTER the reasoning text length and
+  // state are already frozen. Without it in the signature the row's signature would be
+  // unchanged at that point and the re-render skipped, so the "Thinking · N tokens"
+  // header (reasoningTokensForPart) would keep the live estimate instead of snapping
+  // to the exact figure.
+  return `${message.id}#${message.role}#${parts}#${meta?.error ?? ""}#${
+    meta?.finishReason ?? ""
+  }#${meta?.usage?.reasoningTokens ?? ""}`;
+}

apps/client/src/features/editor/components/footnote/footnote-definition-view.tsx

@@ -1,25 +1,45 @@
 import { NodeViewContent, NodeViewProps, NodeViewWrapper } from "@tiptap/react";
 import { useTranslation } from "react-i18next";
-import { getFootnoteNumber } from "@docmost/editor-ext";
+import { getFootnoteNumber, getFootnoteRefCount } from "@docmost/editor-ext";
 import classes from "./footnote.module.css";
 
+/**
+ * A 0-based backlink index -> its lowercase letter label (0 -> "a", 25 -> "z",
+ * 26 -> "aa", ...), matching the Pandoc/Wikipedia "↩ a b c" convention.
+ */
+export function backlinkLabel(index: number): string {
+  let out = "";
+  let x = index;
+  while (x >= 0) {
+    out = String.fromCharCode(97 + (x % 26)) + out;
+    x = Math.floor(x / 26) - 1;
+  }
+  return out;
+}
+
 /**
  * NodeView for a single footnote definition: a decorative number marker, the
  * editable content (NodeViewContent), and a "↩" back-link to its reference.
  * The number is derived from the document (not stored).
+ *
+ * After #166 a footnote can be referenced more than once (one number, one
+ * definition, N forward links). When it is, the back-link becomes a row of
+ * per-occurrence links — ↩ a b c … — each scrolling to its own reference (#168);
+ * a single-reference footnote keeps the plain ↩.
  */
 export default function FootnoteDefinitionView(props: NodeViewProps) {
   const { node, editor } = props;
   const { t } = useTranslation();
   const id = node.attrs.id as string;
 
-  // Read the cached number from the numbering plugin (computed once per doc
-  // change) rather than recomputing the whole map on every render.
+  // Read the cached number/ref-count from the numbering plugin (computed once
+  // per doc change) rather than recomputing the whole map on every render.
   const number = getFootnoteNumber(editor.state, id) ?? "?";
+  const refCount = getFootnoteRefCount(editor.state, id);
 
-  const handleBack = (e: React.MouseEvent) => {
+  const jumpTo = (e: React.MouseEvent, index: number) => {
     e.preventDefault();
-    editor.commands.scrollToReference(id);
+    editor.commands.scrollToReference(id, index);
   };
 
   return (
@@ -42,16 +62,47 @@ export default function FootnoteDefinitionView(props: NodeViewProps) {
       >
         {number}.
       </span>
-      <span
-        className={classes.backLink}
-        contentEditable={false}
-        onClick={handleBack}
-        role="button"
-        aria-label={t("Back to reference")}
-        title={t("Back to reference")}
-      >
-        ↩
-      </span>
+      {refCount > 1 ? (
+        // Multiple references -> ↩ followed by one lettered link per occurrence.
+        <span
+          className={classes.backLinks}
+          contentEditable={false}
+          role="group"
+          aria-label={t("Back to references")}
+        >
+          <span className={classes.backLinkArrow} aria-hidden="true">
+            ↩
+          </span>
+          {Array.from({ length: refCount }, (_, i) => (
+            <span
+              key={i}
+              className={classes.backLink}
+              onClick={(e) => jumpTo(e, i)}
+              role="button"
+              aria-label={t("Back to reference {{label}}", {
+                label: backlinkLabel(i),
+              })}
+              title={t("Back to reference {{label}}", {
+                label: backlinkLabel(i),
+              })}
+            >
+              {backlinkLabel(i)}
+            </span>
+          ))}
+        </span>
+      ) : (
+        // Single reference -> the plain ↩ (unchanged behavior).
+        <span
+          className={classes.backLink}
+          contentEditable={false}
+          onClick={(e) => jumpTo(e, 0)}
+          role="button"
+          aria-label={t("Back to reference")}
+          title={t("Back to reference")}
+        >
+          ↩
+        </span>
+      )}
     </NodeViewWrapper>
   );
 }

apps/client/src/features/editor/components/footnote/footnote-views.structure.test.tsx

@@ -1,5 +1,5 @@
-import { describe, it, expect, vi } from "vitest";
-import { render } from "@testing-library/react";
+import { describe, it, expect, vi, afterEach } from "vitest";
+import { render, fireEvent } from "@testing-library/react";
 
 /**
  * Structural regression guard for #146 (PR #147).
@@ -36,10 +36,14 @@ vi.mock("react-i18next", () => ({
   useTranslation: () => ({ t: (key: string) => key }),
 }));
 
-// footnote-definition-view reads a cached number from the numbering plugin;
-// stub it so we don't need a live ProseMirror state.
+// footnote-definition-view reads a cached number + reference count from the
+// numbering plugin; stub them so we don't need a live ProseMirror state. The
+// ref-count is a hoisted mutable so a test can drive the single-vs-multi
+// backlink branch (#168). Default 1 = single reference (the #146 cases).
+const { mockRefCount } = vi.hoisted(() => ({ mockRefCount: { value: 1 } }));
 vi.mock("@docmost/editor-ext", () => ({
   getFootnoteNumber: () => 1,
+  getFootnoteRefCount: () => mockRefCount.value,
 }));
 
 // Mocks so CodeBlockView renders cheaply (no MantineProvider, no matchMedia).
@@ -59,7 +63,8 @@ vi.mock("@mantine/core", () => ({
   ),
 }));
 vi.mock("@/components/common/copy-button", () => ({
-  CopyButton: ({ children }: any) => children({ copied: false, copy: () => {} }),
+  CopyButton: ({ children }: any) =>
+    children({ copied: false, copy: () => {} }),
 }));
 vi.mock("@tabler/icons-react", () => ({
   IconCheck: () => null,
@@ -70,7 +75,9 @@ vi.mock("@/features/editor/components/code-block/mermaid-view.tsx", () => ({
 }));
 
 import FootnotesListView from "./footnotes-list-view";
-import FootnoteDefinitionView from "./footnote-definition-view";
+import FootnoteDefinitionView, {
+  backlinkLabel,
+} from "./footnote-definition-view";
 import CodeBlockView from "../code-block/code-block-view";
 
 // Minimal NodeViewProps stub: definition view only touches node.attrs.id and
@@ -141,3 +148,84 @@ describe("#146 editable NodeView contentDOM-first invariant", () => {
     },
   );
 });
+
+// #168: a footnote referenced more than once shows one lettered backlink per
+// occurrence (↩ a b c), each scrolling to its own reference; a single-reference
+// footnote keeps the plain ↩.
+describe("#168 footnote definition multi-backlinks", () => {
+  afterEach(() => {
+    // Reset the shared ref-count mock so other tests see a single reference.
+    mockRefCount.value = 1;
+  });
+
+  const makeProps = () =>
+    ({
+      node: { attrs: { id: "fn-1" }, textContent: "" },
+      editor: {
+        state: {},
+        isEditable: true,
+        commands: { scrollToReference: vi.fn() },
+      },
+      getPos: () => 0,
+      updateAttributes: () => {},
+      deleteNode: () => {},
+    }) as any;
+
+  it("renders one lettered backlink per reference (a, b, c) plus the ↩ arrow", () => {
+    mockRefCount.value = 3;
+    const { getByTestId } = render(<FootnoteDefinitionView {...makeProps()} />);
+    const wrapper = getByTestId("nvw");
+
+    const links = wrapper.querySelectorAll('[role="button"]');
+    expect(Array.from(links).map((l) => l.textContent)).toEqual([
+      "a",
+      "b",
+      "c",
+    ]);
+    // The ↩ arrow is present (as decorative chrome, not a button).
+    expect(wrapper.textContent).toContain("↩");
+  });
+
+  it("clicking the n-th backlink scrolls to the n-th occurrence (0-based)", () => {
+    mockRefCount.value = 3;
+    const props = makeProps();
+    const { getByTestId } = render(<FootnoteDefinitionView {...props} />);
+    const links = getByTestId("nvw").querySelectorAll('[role="button"]');
+
+    fireEvent.click(links[1]); // "b"
+    expect(props.editor.commands.scrollToReference).toHaveBeenCalledWith(
+      "fn-1",
+      1,
+    );
+  });
+
+  it("a single-reference footnote renders just one ↩ (no letters)", () => {
+    mockRefCount.value = 1;
+    const props = makeProps();
+    const { getByTestId } = render(<FootnoteDefinitionView {...props} />);
+    const wrapper = getByTestId("nvw");
+
+    const links = wrapper.querySelectorAll('[role="button"]');
+    expect(links.length).toBe(1);
+    expect(links[0].textContent).toBe("↩");
+
+    fireEvent.click(links[0]);
+    expect(props.editor.commands.scrollToReference).toHaveBeenCalledWith(
+      "fn-1",
+      0,
+    );
+  });
+});
+
+// #185 re-review pt 7: backlinkLabel is base-26 (a..z, then aa…). The component
+// tests only cover a,b,c (index 0-2); pin the >= 26 carry boundary.
+describe("backlinkLabel base-26 boundary (#168)", () => {
+  it("maps 0->a, 25->z, 26->aa, 27->ab, 51->az, 52->ba", () => {
+    expect(backlinkLabel(0)).toBe("a");
+    expect(backlinkLabel(25)).toBe("z");
+    expect(backlinkLabel(26)).toBe("aa");
+    expect(backlinkLabel(27)).toBe("ab");
+    expect(backlinkLabel(51)).toBe("az");
+    expect(backlinkLabel(52)).toBe("ba");
+  });
+});

apps/client/src/features/editor/components/footnote/footnote.module.css

@@ -115,3 +115,18 @@
 .backLink:hover {
   text-decoration: underline;
 }
+
+/* Multi-backlink row (#168): ↩ a b c — one lettered link per reference
+   occurrence. Sits on the right, after the content, like the single ↩. */
+.backLinks {
+  flex: 0 0 auto;
+  display: inline-flex;
+  align-items: baseline;
+  gap: 0.3em;
+  user-select: none;
+}
+
+.backLinkArrow {
+  color: var(--mantine-color-dimmed);
+  font-size: 0.9em;
+}

apps/client/src/features/page/queries/page-query.ts

@@ -274,7 +274,10 @@ export function useRestorePageMutation() {
       queryClient.setQueryData<IPage>(["pages", restoredPage.slugId], merge);
     },
     onError: (error) => {
-      notifications.show({ message: t("Failed to restore page"), color: "red" });
+      notifications.show({
+        message: t("Failed to restore page"),
+        color: "red",
+      });
     },
   });
 }
@@ -285,10 +288,10 @@ export function useGetSidebarPagesQuery(
   return useInfiniteQuery({
     queryKey: ["sidebar-pages", data],
     enabled: !!data?.pageId || !!data?.spaceId,
-    queryFn: ({ pageParam }) => getSidebarPages({ ...data, cursor: pageParam, limit: 100 }),
+    queryFn: ({ pageParam }) =>
+      getSidebarPages({ ...data, cursor: pageParam, limit: 100 }),
     initialPageParam: undefined,
-    getNextPageParam: (lastPage) =>
-      lastPage.meta?.nextCursor ?? undefined,
+    getNextPageParam: (lastPage) => lastPage.meta?.nextCursor ?? undefined,
   });
 }
 
@@ -296,11 +299,14 @@ export function useGetRootSidebarPagesQuery(data: SidebarPagesParams) {
   return useInfiniteQuery({
     queryKey: ["root-sidebar-pages", data.spaceId],
     queryFn: async ({ pageParam }) => {
-      return getSidebarPages({ spaceId: data.spaceId, cursor: pageParam, limit: 100 });
+      return getSidebarPages({
+        spaceId: data.spaceId,
+        cursor: pageParam,
+        limit: 100,
+      });
     },
     initialPageParam: undefined,
-    getNextPageParam: (lastPage) =>
-      lastPage.meta?.nextCursor ?? undefined,
+    getNextPageParam: (lastPage) => lastPage.meta?.nextCursor ?? undefined,
   });
 }
 
@@ -323,12 +329,17 @@ export function usePageBreadcrumbsQuery(
   });
 }
 
-export async function fetchAllAncestorChildren(params: SidebarPagesParams) {
+export async function fetchAllAncestorChildren(
+  params: SidebarPagesParams,
+  // `fresh: true` forces a server refetch (staleTime 0) — used by the reconnect
+  // refresh (#159 #8), which must NOT receive the 30-min-cached children.
+  opts?: { fresh?: boolean },
+) {
   // not using a hook here, so we can call it inside a useEffect hook
   const response = await queryClient.fetchQuery({
     queryKey: ["sidebar-pages", params],
     queryFn: () => getAllSidebarPages(params),
-    staleTime: 30 * 60 * 1000,
+    staleTime: opts?.fresh ? 0 : 30 * 60 * 1000,
   });
 
   const allItems = response.pages.flatMap((page) => page.items);
@@ -347,11 +358,15 @@ export function useRecentChangesQuery(spaceId?: string) {
   });
 }
 
-export function useCreatedByQuery(params?: { userId?: string; spaceId?: string }) {
+export function useCreatedByQuery(params?: {
+  userId?: string;
+  spaceId?: string;
+}) {
   const { userId, spaceId } = params ?? {};
   return useInfiniteQuery({
     queryKey: ["pages-created-by-user", { userId, spaceId }],
-    queryFn: ({ pageParam }) => getCreatedByPages({ userId, spaceId, cursor: pageParam, limit: 15 }),
+    queryFn: ({ pageParam }) =>
+      getCreatedByPages({ userId, spaceId, cursor: pageParam, limit: 15 }),
     initialPageParam: undefined as string | undefined,
     getNextPageParam: (lastPage) =>
       lastPage.meta.hasNextPage ? lastPage.meta.nextCursor : undefined,

apps/client/src/features/page/tree/components/space-tree.tsx

@@ -29,9 +29,11 @@ import {
   collectBranchIds,
   openBranches,
   closeIds,
+  loadedOpenBranchIds,
 } from "@/features/page/tree/utils/utils.ts";
 import { SpaceTreeNode } from "@/features/page/tree/types.ts";
 import { treeModel } from "@/features/page/tree/model/tree-model";
+import { socketAtom } from "@/features/websocket/atoms/socket-atom.ts";
 import {
   getPageBreadcrumbs,
   getSpaceTree,
@@ -39,11 +41,7 @@ import {
 import { IPage } from "@/features/page/types/page.types.ts";
 import { extractPageSlugId } from "@/lib";
 import { isCompactPageTreeEnabled } from "@/lib/config.ts";
-import {
-  DocTree,
-  ROW_HEIGHT_COMPACT,
-  ROW_HEIGHT_STANDARD,
-} from "./doc-tree";
+import { DocTree, ROW_HEIGHT_COMPACT, ROW_HEIGHT_STANDARD } from "./doc-tree";
 import { SpaceTreeRow } from "./space-tree-row";
 
 interface SpaceTreeProps {
@@ -193,6 +191,54 @@ const SpaceTree = forwardRef<SpaceTreeApi, SpaceTreeProps>(function SpaceTree(
     [openTreeNodes],
   );
 
+  // Latest tree + open-state for the reconnect handler (its closure would
+  // otherwise read stale snapshots).
+  const [socket] = useAtom(socketAtom);
+  const dataRef = useRef(data);
+  dataRef.current = data;
+  const openIdsRef = useRef(openIds);
+  openIdsRef.current = openIds;
+
+  // Reconnect refresh (#159 #8): on a socket reconnect, re-fetch and reconcile
+  // the children of every currently-open, already-loaded branch of THIS space,
+  // so a move/rename/delete that happened INSIDE a loaded branch while events
+  // were missed (laptop sleep / wifi gap) is reflected instead of left stale.
+  // The ROOT level is reconciled separately by the root-query refetch +
+  // mergeRootTrees; an UNLOADED branch is skipped (lazy-load fetches it fresh on
+  // expand). No first-connect guard is needed: space-tree usually mounts AFTER
+  // the initial connect, so every `connect` it sees is a reconnect; the rare
+  // initial-connect case has an empty tree, so the refresh is a harmless no-op.
+  useEffect(() => {
+    if (!socket) return;
+    const onConnect = async () => {
+      const effectSpaceId = spaceIdRef.current;
+      const branchIds = loadedOpenBranchIds(
+        dataRef.current.filter((n) => n?.spaceId === effectSpaceId),
+        openIdsRef.current,
+      );
+      if (branchIds.length === 0) return;
+      for (const id of branchIds) {
+        try {
+          // `fresh: true` bypasses the 30-min sidebar-pages cache so the
+          // reconcile sees the server's CURRENT children (handler-order
+          // independent — no reliance on the global reconnect invalidation).
+          const fresh = await fetchAllAncestorChildren(
+            { pageId: id, spaceId: effectSpaceId },
+            { fresh: true },
+          );
+          if (spaceIdRef.current !== effectSpaceId) return; // space switched
+          setData((prev) => treeModel.reconcileChildren(prev, id, fresh));
+        } catch (err) {
+          console.error("[tree] reconnect branch refresh failed", err);
+        }
+      }
+    };
+    socket.on("connect", onConnect);
+    return () => {
+      socket.off("connect", onConnect);
+    };
+  }, [socket, setData]);
+
   const handleToggle = useCallback(
     async (id: string, isOpen: boolean) => {
       setOpenTreeNodes((prev) => ({ ...prev, [id]: isOpen }));
@@ -245,8 +291,7 @@ const SpaceTree = forwardRef<SpaceTreeApi, SpaceTreeProps>(function SpaceTree(
       notifications.show({
         color: "red",
         message: t("Couldn't expand the tree: {{reason}}", {
-          reason:
-            err?.response?.data?.message ?? err?.message ?? String(err),
+          reason: err?.response?.data?.message ?? err?.message ?? String(err),
         }),
       });
     } finally {
@@ -262,11 +307,11 @@ const SpaceTree = forwardRef<SpaceTreeApi, SpaceTreeProps>(function SpaceTree(
     setOpenTreeNodes((prev) => closeIds(prev, ids));
   }, [filteredData, setOpenTreeNodes]);
 
-  useImperativeHandle(
-    ref,
-    () => ({ expandAll, collapseAll, isExpanding }),
-    [expandAll, collapseAll, isExpanding],
-  );
+  useImperativeHandle(ref, () => ({ expandAll, collapseAll, isExpanding }), [
+    expandAll,
+    collapseAll,
+    isExpanding,
+  ]);
 
   // Stable callbacks for DocTree. Without these, every parent render recreates
   // the props and tears down every row's draggable/dropTarget subscription,

apps/client/src/features/page/tree/model/tree-model.ts

@@ -1,4 +1,4 @@
-import type { TreeNode, SiblingsInfo } from './tree-model.types';
+import type { TreeNode, SiblingsInfo } from "./tree-model.types";
 
 function findInternal<T extends object>(
   nodes: TreeNode<T>[],
@@ -19,7 +19,10 @@ export const treeModel = {
     return findInternal(tree, id)?.node ?? null;
   },
 
-  path<T extends object>(tree: TreeNode<T>[], id: string): TreeNode<T>[] | null {
+  path<T extends object>(
+    tree: TreeNode<T>[],
+    id: string,
+  ): TreeNode<T>[] | null {
     const found = findInternal(tree, id);
     if (!found) return null;
     return [...found.parents, found.node];
@@ -123,6 +126,23 @@ export const treeModel = {
       return treeModel.insert(tree, null, node, index(tree));
     }
     const parent = treeModel.find(tree, parentId);
+    // The parent is in the tree but its children have NOT been lazy-loaded yet
+    // (`children === undefined`, distinct from a loaded-but-empty `[]`). Inserting
+    // here would MATERIALIZE a misleading partial child list (`[node]`) that
+    // defeats the lazy-load gate — which fetches only when children are
+    // absent/empty — so the parent's OTHER real children would never load and the
+    // moved/added node would be the only one shown (a silent data loss, #159 #1).
+    // Instead, leave the children unloaded and just flag `hasChildren` so the
+    // chevron appears; expanding fetches the FULL set (including this node).
+    if (parent && parent.children === undefined) {
+      return treeModel.update(
+        tree,
+        parentId,
+        // hasChildren is not part of the generic T constraint; tree nodes carry
+        // it. Cast narrowly so this stays a single, well-understood exception.
+        { hasChildren: true } as unknown as Omit<Partial<T>, "id" | "children">,
+      );
+    }
     const kids = (parent?.children as TreeNode<T>[] | undefined) ?? [];
     return treeModel.insert(tree, parentId, node, index(kids));
   },
@@ -203,6 +223,48 @@ export const treeModel = {
     return touched ? out : tree;
   },
 
+  // Replace a parent's DIRECT children with the authoritative `fresh` set while
+  // PRESERVING each surviving child's already-loaded grandchildren (deeper
+  // expansion). Unlike `appendChildren` (add-only), this DROPS children that are
+  // no longer present and reorders to `fresh` — so a move/delete/rename that
+  // happened inside a loaded branch while events were missed (a socket reconnect
+  // gap) is reflected, not left stale (#159 #8). Only used to reconcile an
+  // already-loaded branch against a fresh fetch; a parent with no loaded children
+  // (`children === undefined`) is left untouched (lazy-load handles it).
+  reconcileChildren<T extends object>(
+    tree: TreeNode<T>[],
+    parentId: string,
+    fresh: TreeNode<T>[],
+  ): TreeNode<T>[] {
+    let touched = false;
+    const walk = (nodes: TreeNode<T>[]): TreeNode<T>[] =>
+      nodes.map((n) => {
+        if (n.id === parentId) {
+          // Only reconcile a branch whose children were actually loaded; an
+          // unloaded parent stays unloaded (lazy-load fetches it fresh later).
+          if (n.children === undefined) return n;
+          const prevById = new Map(n.children.map((c) => [c.id, c]));
+          const merged = fresh.map((f) => {
+            const prev = prevById.get(f.id);
+            // Preserve the surviving child's previously loaded grandchildren so
+            // deeper expansion is not collapsed by the reconcile.
+            return prev?.children !== undefined
+              ? { ...f, children: prev.children }
+              : f;
+          });
+          touched = true;
+          return { ...n, children: merged };
+        }
+        if (n.children) {
+          const next = walk(n.children);
+          if (next !== n.children) return { ...n, children: next };
+        }
+        return n;
+      });
+    const out = walk(tree);
+    return touched ? out : tree;
+  },
+
   place<T extends object>(
     tree: TreeNode<T>[],
     sourceId: string,
@@ -242,9 +304,10 @@ export const treeModel = {
   move<T extends object>(
     tree: TreeNode<T>[],
     sourceId: string,
-    op: import('./tree-model.types').DropOp,
-  ): { tree: TreeNode<T>[]; result: import('./tree-model.types').DropResult } {
-    if (sourceId === op.targetId) return { tree, result: { parentId: null, index: 0 } };
+    op: import("./tree-model.types").DropOp,
+  ): { tree: TreeNode<T>[]; result: import("./tree-model.types").DropResult } {
+    if (sourceId === op.targetId)
+      return { tree, result: { parentId: null, index: 0 } };
     if (!treeModel.find(tree, sourceId) || !treeModel.find(tree, op.targetId)) {
       return { tree, result: { parentId: null, index: 0 } };
     }
@@ -255,7 +318,7 @@ export const treeModel = {
     let parentId: string | null;
     let index: number;
 
-    if (op.kind === 'make-child') {
+    if (op.kind === "make-child") {
       parentId = op.targetId;
       const target = treeModel.find(tree, op.targetId)!;
       index = target.children?.length ?? 0;
@@ -264,9 +327,8 @@ export const treeModel = {
       parentId = info.parentId;
       const sourceInfo = treeModel.siblingsOf(tree, sourceId)!;
       const sameParent = sourceInfo.parentId === parentId;
-      const adjust =
-        sameParent && sourceInfo.index < info.index ? -1 : 0;
-      index = info.index + adjust + (op.kind === 'reorder-after' ? 1 : 0);
+      const adjust = sameParent && sourceInfo.index < info.index ? -1 : 0;
+      index = info.index + adjust + (op.kind === "reorder-after" ? 1 : 0);
     }
 
     const next = treeModel.place(tree, sourceId, { parentId, index });

apps/client/src/features/page/tree/utils/utils.test.ts

@@ -6,6 +6,8 @@ import {
   collectBranchIds,
   openBranches,
   closeIds,
+  mergeRootTrees,
+  loadedOpenBranchIds,
 } from "./utils";
 import type { IPage } from "@/features/page/types/page.types.ts";
 import type { SpaceTreeNode } from "@/features/page/tree/types.ts";
@@ -44,10 +46,7 @@ function flatNode(
 }
 
 // Nested SpaceTreeNode factory for collectAllIds / collectBranchIds.
-function treeNode(
-  id: string,
-  children: SpaceTreeNode[] = [],
-): SpaceTreeNode {
+function treeNode(id: string, children: SpaceTreeNode[] = []): SpaceTreeNode {
   return {
     id,
     slugId: `slug-${id}`,
@@ -94,11 +93,7 @@ describe("collectBranchIds", () => {
       ]),
       treeNode("root2", [treeNode("leaf3")]),
     ];
-    expect(collectBranchIds(tree).sort()).toEqual([
-      "branch1",
-      "root",
-      "root2",
-    ]);
+    expect(collectBranchIds(tree).sort()).toEqual(["branch1", "root", "root2"]);
   });
 
   it("returns [] for a leaf-only tree", () => {
@@ -273,3 +268,95 @@ describe("closeIds", () => {
     expect(twice).toEqual({ keep: true, a: false, b: false });
   });
 });
+
+describe("mergeRootTrees (#159 #2 reconnect reconcile)", () => {
+  // Root node with a position and optional already-loaded children.
+  function root(
+    id: string,
+    position: string,
+    children?: SpaceTreeNode[],
+  ): SpaceTreeNode {
+    return {
+      id,
+      slugId: `slug-${id}`,
+      name: id.toUpperCase(),
+      icon: undefined,
+      position,
+      spaceId: "space-1",
+      parentPageId: null as unknown as string,
+      hasChildren: !!children?.length,
+      children: children as SpaceTreeNode[],
+    };
+  }
+
+  it("DROPS a stale root that is absent from the incoming (authoritative) set", () => {
+    // 'ghost' was a root before the gap; the server's current roots no longer
+    // include it (deleted / moved under another page). It must not linger.
+    const prev = [root("a", "a0"), root("ghost", "a2"), root("b", "a4")];
+    const incoming = [root("a", "a0"), root("b", "a4")];
+    const merged = mergeRootTrees(prev, incoming);
+    expect(merged.map((n) => n.id)).toEqual(["a", "b"]);
+    expect(merged.find((n) => n.id === "ghost")).toBeUndefined();
+  });
+
+  it("PRESERVES a surviving root's lazy-loaded children (subtree not lost on refetch)", () => {
+    const loadedChild = root("a1", "a0");
+    const prev = [root("a", "a0", [loadedChild])];
+    // The root query returns only top-level roots (no children).
+    const incoming = [root("a", "a0")];
+    const merged = mergeRootTrees(prev, incoming);
+    expect(merged[0].children?.map((c) => c.id)).toEqual(["a1"]);
+  });
+
+  it("ADDS a new incoming root", () => {
+    const prev = [root("a", "a0")];
+    const incoming = [root("a", "a0"), root("new", "a2")];
+    const merged = mergeRootTrees(prev, incoming);
+    expect(merged.map((n) => n.id)).toEqual(["a", "new"]);
+  });
+
+  it("REFRESHES a surviving root's own fields from the incoming copy (e.g. rename)", () => {
+    const prev = [{ ...root("a", "a0"), name: "OLD" }];
+    const incoming = [{ ...root("a", "a0"), name: "NEW" }];
+    const merged = mergeRootTrees(prev, incoming);
+    expect(merged[0].name).toBe("NEW");
+  });
+});
+
+describe("loadedOpenBranchIds (#159 #8 reconnect refresh targets)", () => {
+  function n(id: string, children?: SpaceTreeNode[]): SpaceTreeNode {
+    return {
+      id,
+      slugId: `slug-${id}`,
+      name: id.toUpperCase(),
+      icon: undefined,
+      position: "a0",
+      spaceId: "space-1",
+      parentPageId: null as unknown as string,
+      hasChildren: !!children,
+      children: children as SpaceTreeNode[],
+    };
+  }
+
+  it("returns OPEN branches whose children are loaded (array)", () => {
+    const tree = [n("a", [n("a1")]), n("b", [n("b1")])];
+    const ids = loadedOpenBranchIds(tree, new Set(["a"]));
+    expect(ids).toEqual(["a"]); // b is closed; a is open+loaded
+  });
+
+  it("skips an open branch whose children are NOT loaded (undefined)", () => {
+    const tree = [n("a")]; // children undefined
+    expect(loadedOpenBranchIds(tree, new Set(["a"]))).toEqual([]);
+  });
+
+  it("includes a loaded-but-empty open branch (a child may have been added during the gap)", () => {
+    const tree = [n("a", [])];
+    expect(loadedOpenBranchIds(tree, new Set(["a"]))).toEqual(["a"]);
+  });
+
+  it("walks nested open+loaded branches (deep chain refreshes every level)", () => {
+    const tree = [n("a", [n("a1", [n("a1a")])])];
+    const ids = loadedOpenBranchIds(tree, new Set(["a", "a1"]));
+    expect(ids.sort()).toEqual(["a", "a1"]);
+  });
+});

apps/client/src/features/page/tree/utils/utils.ts

@@ -214,21 +214,59 @@ export function appendNodeChildren(
 }
 
 /**
- * Merge root nodes; keep existing ones intact, append new ones,
+ * Reconcile the loaded root nodes to the authoritative INCOMING set (the
+ * server's complete current roots for the space), preserving any lazy-loaded
+ * children/subtree of a root that still exists.
+ *
+ * This runs only once all root pages are fetched, so `incomingRoots` is the full
+ * server root set and is authoritative for WHICH roots exist:
+ *  - a root in BOTH: kept, with its own fields refreshed from `incoming` (so a
+ *    rename/move during a gap shows) while PRESERVING its previously lazy-loaded
+ *    `children` (expanded subtrees + open-state survive a refetch);
+ *  - a root only in `incoming`: a new root, added as-is;
+ *  - a root only in `prev`: it was DELETED or moved under another page while we
+ *    were not receiving events (e.g. a socket reconnect after a sleep/wifi gap).
+ *    It is DROPPED instead of lingering as a 404 "ghost" root (#159 #2). The old
+ *    append-only merge kept it forever.
  */
 export function mergeRootTrees(
   prevRoots: SpaceTreeNode[],
   incomingRoots: SpaceTreeNode[],
 ): SpaceTreeNode[] {
-  const seen = new Set(prevRoots.map((r) => r.id));
+  const prevById = new Map(prevRoots.map((r) => [r.id, r]));
 
-  // add new roots that were not present before
-  const merged = [...prevRoots];
-  incomingRoots.forEach((node) => {
-    if (!seen.has(node.id)) merged.push(node);
+  const reconciled = incomingRoots.map((incoming) => {
+    const prev = prevById.get(incoming.id);
+    // Preserve the previously loaded children/subtree (the root query returns
+    // only top-level roots, so `incoming` carries no children); refresh the
+    // node's own fields from the authoritative incoming copy.
+    return prev ? { ...incoming, children: prev.children } : incoming;
   });
 
-  return sortPositionKeys(merged);
+  return sortPositionKeys(reconciled);
+}
+
+/**
+ * Ids of branches a socket-reconnect refresh should re-fetch and reconcile
+ * (#159 #8): a node that is currently OPEN and whose children are LOADED
+ * (`children` is an array — possibly empty). An unloaded branch (`children ===
+ * undefined`) is skipped because lazy-load fetches it fresh on the next expand,
+ * so there is nothing stale to reconcile. Walks the whole tree (a deep open
+ * chain refreshes every loaded level).
+ */
+export function loadedOpenBranchIds(
+  tree: SpaceTreeNode[],
+  openIds: ReadonlySet<string>,
+): string[] {
+  const ids: string[] = [];
+  const walk = (nodes: SpaceTreeNode[]) => {
+    for (const n of nodes) {
+      if (openIds.has(n.id) && Array.isArray(n.children)) ids.push(n.id);
+      if (n.children) walk(n.children);
+    }
+  };
+  walk(tree);
+  return ids;
 }
 
 // Collect every node id in the tree (roots, branches, leaves). Used by

apps/client/src/features/websocket/tree-socket-reducers.test.ts

@@ -81,6 +81,38 @@ describe("applyMoveTreeNode", () => {
     ]);
   });
 
+  it("does NOT create a partial child list when the destination is loaded-but-collapsed (children unloaded) — keeps it lazy-loadable (#159)", () => {
+    // `dstCollapsed` is in the tree but its children were never lazy-loaded
+    // (children === undefined). The OLD behavior inserted `src` as the ONLY
+    // child ([src]), which defeated the lazy-load gate and HID the parent's
+    // other real children. Now the move leaves children unloaded (so expanding
+    // fetches the FULL set, including src) and just flags hasChildren.
+    const tree: SpaceTreeNode[] = [
+      node("dstCollapsed", {
+        position: "a0",
+        hasChildren: false,
+        children: undefined as unknown as SpaceTreeNode[],
+      }),
+      node("src", { position: "a9" }),
+    ];
+    const next = applyMoveTreeNode(tree, {
+      id: "src",
+      parentId: "dstCollapsed",
+      oldParentId: null,
+      index: 0,
+      position: "a4",
+      pageData: {},
+    });
+    const dst = treeModel.find(next, "dstCollapsed");
+    // Children stay unloaded -> the lazy-load gate fetches the FULL set (incl.
+    // src) on expand, rather than showing a misleading partial [src] list.
+    expect(dst?.children).toBeUndefined();
+    expect(dst?.hasChildren).toBe(true);
+    // src moved away from its old root slot (it lives under dstCollapsed
+    // server-side and reappears when the parent is expanded/loaded).
+    expect(next.map((n) => n.id)).not.toContain("src");
+  });
+
   it("flips the OLD parent's hasChildren to false when it is left childless", () => {
     // src is the only child of `old`; moving it to `dst` empties `old`.
     const tree: SpaceTreeNode[] = [
@@ -164,7 +196,9 @@ describe("applyDeleteTreeNode", () => {
             position: "a1",
             parentPageId: "p",
             hasChildren: true,
-            children: [node("grandchild", { position: "a1", parentPageId: "child" })],
+            children: [
+              node("grandchild", { position: "a1", parentPageId: "child" }),
+            ],
           }),
         ],
       }),

apps/client/src/features/workspace/components/settings/components/ai-mcp-server-form.tsx

@@ -11,6 +11,7 @@ import {
   Switch,
   TagsInput,
   Text,
+  Textarea,
   TextInput,
 } from "@mantine/core";
 import { useForm } from "@mantine/form";
@@ -35,6 +36,8 @@ const formSchema = z.object({
   // Write-only secret buffer. Empty string means "do not change" (unless cleared).
   authHeader: z.string(),
   toolAllowlist: z.array(z.string()),
+  // Admin-authored prompt guidance (#180). Capped to mirror the DTO MaxLength.
+  instructions: z.string().max(4000),
   enabled: z.boolean(),
 });
 
@@ -63,6 +66,7 @@ function buildInitialValues(server?: IAiMcpServer): FormValues {
     toolAllowlist: Array.isArray(server?.toolAllowlist)
       ? server.toolAllowlist
       : [],
+    instructions: server?.instructions ?? "",
     enabled: server?.enabled ?? true,
   };
 }
@@ -124,6 +128,8 @@ export default function AiMcpServerForm({
         transport: values.transport,
         url: values.url,
         toolAllowlist: values.toolAllowlist,
+        // Always sent: a blank value clears the stored guidance (server -> null).
+        instructions: values.instructions,
         enabled: values.enabled,
       };
       // Only attach headers when set or explicitly cleared (omit => unchanged).
@@ -135,6 +141,8 @@ export default function AiMcpServerForm({
         transport: values.transport,
         url: values.url,
         toolAllowlist: values.toolAllowlist,
+        // Blank => server stores null (no guidance).
+        instructions: values.instructions,
         enabled: values.enabled,
       };
       // On create, only a typed value matters (no prior stored headers).
@@ -158,10 +166,7 @@ export default function AiMcpServerForm({
 
   return (
     <Stack>
-      <TextInput
-        label={t("Server name")}
-        {...form.getInputProps("name")}
-      />
+      <TextInput label={t("Server name")} {...form.getInputProps("name")} />
 
       <Select
         label={t("Transport")}
@@ -177,7 +182,7 @@ export default function AiMcpServerForm({
         // Clarify that the value is sent verbatim as the Authorization header,
         // so the user supplies the full scheme (no implicit Bearer prefix).
         description={t(
-          "Sent verbatim as the value of the Authorization header (e.g. \"Bearer <token>\" or \"Basic <base64>\").",
+          'Sent verbatim as the value of the Authorization header (e.g. "Bearer <token>" or "Basic <base64>").',
         )}
         // Placeholder hints whether headers are stored; the value is never shown.
         placeholder={hasHeaders ? t("•••• set") : ""}
@@ -208,6 +213,20 @@ export default function AiMcpServerForm({
         {...form.getInputProps("toolAllowlist")}
       />
 
+      <Textarea
+        label={t("Instructions")}
+        // Hint that the text is injected into the agent's system prompt and that
+        // the server's tools are namespaced under <name>_* (the prompt header).
+        description={t(
+          "Optional guidance for the agent on how and when to use this server's tools. Injected into the system prompt. The server's tools are namespaced as \"<server name>_*\".",
+        )}
+        autosize
+        minRows={2}
+        maxRows={8}
+        maxLength={4000}
+        {...form.getInputProps("instructions")}
+      />
+
       <Switch
         label={t("Enabled")}
         checked={form.values.enabled}

apps/client/src/features/workspace/services/ai-mcp-server-service.ts

@@ -14,6 +14,9 @@ export interface IAiMcpServer {
   enabled: boolean;
   toolAllowlist: string[] | null;
   hasHeaders: boolean;
+  // Admin-authored guidance injected into the agent system prompt (#180).
+  // NON-secret, so it IS returned. Null when no guidance is configured.
+  instructions: string | null;
 }
 
 // Create payload. `headers` is write-only: omit => no auth headers.
@@ -25,6 +28,8 @@ export interface IAiMcpServerCreate {
   // never returned.
   headers?: Record<string, string>;
   toolAllowlist?: string[];
+  // Admin-authored prompt guidance (#180). Blank => stored as null.
+  instructions?: string;
   enabled?: boolean;
 }
 
@@ -39,6 +44,8 @@ export interface IAiMcpServerUpdate {
   url?: string;
   headers?: Record<string, string>;
   toolAllowlist?: string[];
+  // Admin-authored prompt guidance (#180). Absent => unchanged; blank => cleared.
+  instructions?: string;
   enabled?: boolean;
 }
 

apps/server/src/core/ai-chat/ai-chat.controller.export.spec.ts

@@ -0,0 +1,159 @@
+import { ForbiddenException } from '@nestjs/common';
+import { AiChatController } from './ai-chat.controller';
+import {
+  planFinalizeAssistant,
+  applyFinalize,
+  flushAssistant,
+  type AssistantFlush,
+} from './ai-chat.service';
+import type { User, Workspace } from '@docmost/db/types/entity.types';
+
+/**
+ * Wiring spec for the #183 `POST /ai-chat/export` endpoint. It must: own-gate via
+ * the chat lookup (workspace-scoped + creator-owned), load the FULL transcript
+ * via findAllByChat, render server-side, and return `{ markdown }`. Exercised by
+ * instantiating the controller with hand-rolled mocks — no Nest graph, no DB.
+ */
+describe('AiChatController.export', () => {
+  const user = { id: 'u1' } as User;
+  const workspace = { id: 'ws1' } as Workspace;
+
+  function makeController(
+    over: {
+      chat?: unknown;
+      rows?: unknown[];
+    } = {},
+  ) {
+    const chat =
+      'chat' in over
+        ? over.chat
+        : { id: 'c1', creatorId: 'u1', title: 'My chat' };
+    const aiChatRepo = {
+      findById: jest.fn().mockResolvedValue(chat),
+    };
+    const aiChatMessageRepo = {
+      findAllByChat: jest.fn().mockResolvedValue(
+        over.rows ?? [
+          {
+            id: 'm1',
+            role: 'user',
+            content: 'hi',
+            metadata: null,
+            status: null,
+          },
+          {
+            id: 'm2',
+            role: 'assistant',
+            content: 'hello',
+            metadata: null,
+            status: 'completed',
+          },
+        ],
+      ),
+    };
+    const controller = new AiChatController(
+      {} as never,
+      aiChatRepo as never,
+      aiChatMessageRepo as never,
+      {} as never,
+    );
+    return { controller, aiChatRepo, aiChatMessageRepo };
+  }
+
+  it('renders the full transcript and returns { markdown }', async () => {
+    const { controller, aiChatMessageRepo } = makeController();
+    const res = await controller.export({ chatId: 'c1' }, user, workspace);
+    expect(aiChatMessageRepo.findAllByChat).toHaveBeenCalledWith('c1', 'ws1');
+    expect(res.markdown).toContain('# My chat');
+    expect(res.markdown).toContain('## 1. You');
+    expect(res.markdown).toContain('## 2. AI agent');
+  });
+
+  it('forbids a chat the user does not own', async () => {
+    const { controller } = makeController({
+      chat: { id: 'c1', creatorId: 'someone-else', title: 'X' },
+    });
+    await expect(
+      controller.export({ chatId: 'c1' }, user, workspace),
+    ).rejects.toBeInstanceOf(ForbiddenException);
+  });
+
+  it('forbids a missing / foreign-workspace chat', async () => {
+    const { controller } = makeController({ chat: null });
+    await expect(
+      controller.export({ chatId: 'c1' }, user, workspace),
+    ).rejects.toBeInstanceOf(ForbiddenException);
+  });
+
+  it('localizes labels when lang=ru is passed', async () => {
+    const { controller } = makeController();
+    const res = await controller.export(
+      { chatId: 'c1', lang: 'ru' },
+      user,
+      workspace,
+    );
+    expect(res.markdown).toContain('## 1. Вы');
+    expect(res.markdown).toContain('## 2. ИИ-агент');
+  });
+});
+
+/**
+ * The terminal-finalize dispatch (#183): the assistant row is INSERTed upfront
+ * as 'streaming' and finalized once on the terminal callback. When the upfront
+ * insert SUCCEEDED (we hold an id) finalize UPDATEs that row; when it FAILED
+ * (assistantId is undefined) finalize falls back to INSERTing the terminal row
+ * so the turn is not lost — the only safety against losing the turn entirely.
+ *
+ * `planFinalizeAssistant` is the pure decision; `applyFinalize` is the REAL
+ * dispatch the service uses, exercised here over a mock repo (not a copy of the
+ * logic) so a production drift would fail the test (#186 review).
+ */
+describe('finalizeAssistant dispatch (planFinalizeAssistant + applyFinalize)', () => {
+  const workspaceId = 'ws1';
+
+  // Drive the SAME applyFinalize the service calls (no duplicated logic).
+  async function dispatchFinalize(
+    repo: { insert: jest.Mock; update: jest.Mock },
+    assistantId: string | undefined,
+    flushed: AssistantFlush,
+  ): Promise<void> {
+    await applyFinalize(
+      repo,
+      planFinalizeAssistant(assistantId),
+      { chatId: 'c1', workspaceId, userId: 'u1' },
+      flushed,
+    );
+  }
+
+  it('plan: update when the upfront insert returned an id', () => {
+    expect(planFinalizeAssistant('a1')).toEqual({ kind: 'update', id: 'a1' });
+  });
+
+  it('plan: insert (fallback) when there is no upfront id', () => {
+    expect(planFinalizeAssistant(undefined)).toEqual({ kind: 'insert' });
+  });
+
+  it('(a) upfront insert succeeded -> finalize UPDATEs the row by id', async () => {
+    const repo = { insert: jest.fn(), update: jest.fn() };
+    const flushed = flushAssistant([], 'final answer', 'completed', {
+      finishReason: 'stop',
+    });
+    await dispatchFinalize(repo, 'a1', flushed);
+    expect(repo.update).toHaveBeenCalledWith('a1', workspaceId, flushed);
+    expect(repo.insert).not.toHaveBeenCalled();
+  });
+
+  it('(b) upfront insert failed -> finalize INSERTs the terminal payload', async () => {
+    const repo = { insert: jest.fn(), update: jest.fn() };
+    const flushed = flushAssistant([], 'partial', 'error', { error: 'boom' });
+    await dispatchFinalize(repo, undefined, flushed);
+    expect(repo.update).not.toHaveBeenCalled();
+    expect(repo.insert).toHaveBeenCalledTimes(1);
+    const arg = repo.insert.mock.calls[0][0];
+    // The fallback insert carries the terminal content/status/metadata.
+    expect(arg.role).toBe('assistant');
+    expect(arg.content).toBe('partial');
+    expect(arg.status).toBe('error');
+    expect((arg.metadata as { error?: string }).error).toBe('boom');
+  });
+});

apps/server/src/core/ai-chat/ai-chat.controller.ts

@@ -20,7 +20,7 @@ import { JwtAuthGuard } from '../../common/guards/jwt-auth.guard';
 import { AuthUser } from '../../common/decorators/auth-user.decorator';
 import { AuthWorkspace } from '../../common/decorators/auth-workspace.decorator';
 import { SkipTransform } from '../../common/decorators/skip-transform.decorator';
-import { User, Workspace } from '@docmost/db/types/entity.types';
+import { AiChat, User, Workspace } from '@docmost/db/types/entity.types';
 import { PaginationOptions } from '@docmost/db/pagination/pagination-options';
 import { AiChatRepo } from '@docmost/db/repos/ai-chat/ai-chat.repo';
 import { AiChatMessageRepo } from '@docmost/db/repos/ai-chat/ai-chat-message.repo';
@@ -31,10 +31,12 @@ import { AiChatService, AiChatStreamBody } from './ai-chat.service';
 import { AiTranscriptionService } from './ai-transcription.service';
 import {
   ChatIdDto,
+  ExportChatDto,
   GetChatMessagesDto,
   RenameChatDto,
 } from './dto/ai-chat.dto';
 import { describeProviderError } from '../../integrations/ai/ai-error.util';
+import { buildChatMarkdown } from './chat-markdown.util';
 
 /**
  * Per-user AI chat API (§6.1). Routes are POST to match this codebase's
@@ -81,6 +83,36 @@ export class AiChatController {
     );
   }
 
+  /**
+   * Export a chat to Markdown (#183). The DB is the single source of truth: the
+   * whole transcript is loaded (oldest -> newest) and rendered server-side. Now
+   * that the assistant row is persisted upfront and per step, an interrupted
+   * turn is included up to its last finished step. Workspace-scoped and owner-
+   * gated via assertOwnedChat (same as the other read endpoints). Returns
+   * `{ markdown }`. `lang` localizes the few fixed labels (default English).
+   */
+  @HttpCode(HttpStatus.OK)
+  @Post('export')
+  async export(
+    @Body() dto: ExportChatDto,
+    @AuthUser() user: User,
+    @AuthWorkspace() workspace: Workspace,
+  ): Promise<{ markdown: string }> {
+    const chat = await this.assertOwnedChat(dto.chatId, user, workspace);
+    const rows = await this.aiChatMessageRepo.findAllByChat(
+      dto.chatId,
+      workspace.id,
+    );
+    const markdown = buildChatMarkdown({
+      title: chat.title ?? null,
+      chatId: dto.chatId,
+      rows,
+      // normalizeLang(undefined) already yields 'en', so no `?? 'en'` is needed.
+      lang: dto.lang,
+    });
+    return { markdown };
+  }
+
   /** Rename a chat. */
   @HttpCode(HttpStatus.OK)
   @Post('rename')
@@ -90,7 +122,11 @@ export class AiChatController {
     @AuthWorkspace() workspace: Workspace,
   ) {
     await this.assertOwnedChat(dto.chatId, user, workspace);
-    await this.aiChatRepo.update(dto.chatId, { title: dto.title }, workspace.id);
+    await this.aiChatRepo.update(
+      dto.chatId,
+      { title: dto.title },
+      workspace.id,
+    );
     return { success: true };
   }
 
@@ -145,7 +181,10 @@ export class AiChatController {
     // Resolve the agent role for this turn BEFORE hijack: existing chats read it
     // from ai_chats.role_id (authoritative), a new chat from body.roleId. The
     // role drives both the persona and the optional model override below.
-    const role = await this.aiChatService.resolveRoleForRequest(workspace, body);
+    const role = await this.aiChatService.resolveRoleForRequest(
+      workspace,
+      body,
+    );
 
     // Resolve the model (applying the role's optional override) BEFORE hijack so
     // an unconfigured provider — including a role pointing at an unconfigured
@@ -232,7 +271,9 @@ export class AiChatController {
     let file = null;
     try {
       // Whisper hard-caps uploads at 25MB; allow a single file.
-      file = await req.file({ limits: { fileSize: 25 * 1024 * 1024, files: 1 } });
+      file = await req.file({
+        limits: { fileSize: 25 * 1024 * 1024, files: 1 },
+      });
     } catch (err: any) {
       if (err?.statusCode === 413) {
         throw new BadRequestException('Audio file too large (max 25MB)');
@@ -283,11 +324,12 @@ export class AiChatController {
     chatId: string,
     user: User,
     workspace: Workspace,
-  ): Promise<void> {
+  ): Promise<AiChat> {
     const chat = await this.aiChatRepo.findById(chatId, workspace.id);
     if (!chat || chat.creatorId !== user.id) {
       throw new ForbiddenException();
     }
+    return chat;
   }
 }
 

apps/server/src/core/ai-chat/ai-chat.prompt.spec.ts

@@ -1,4 +1,4 @@
-import { buildSystemPrompt } from './ai-chat.prompt';
+import { buildSystemPrompt, buildMcpToolingBlock } from './ai-chat.prompt';
 import { Workspace } from '@docmost/db/types/entity.types';
 
 /**
@@ -161,3 +161,81 @@ describe('buildSystemPrompt current-page context', () => {
     expect(pageIdx).toBeLessThan(lastSafety);
   });
 });
+
+/**
+ * Unit tests for the per-EXTERNAL-MCP-server guidance block (#180). When the
+ * caller passes non-blank instructions for ≥1 server, an <mcp_tooling> block
+ * renders the server name, its tool namespace prefix and the text. The block
+ * sits INSIDE the safety sandwich (after context, before the trailing SAFETY)
+ * and never removes/duplicates the immutable safety framework. An empty list or
+ * all-blank text renders nothing.
+ */
+describe('buildSystemPrompt mcp tooling guidance', () => {
+  const workspace = { name: 'Acme' } as unknown as Workspace;
+  const SAFETY_MARKER = 'Operating rules (always in effect)';
+
+  // The block's CONTENT and its empty/undefined/all-blank handling are covered by
+  // the buildMcpToolingBlock unit tests below; here we only pin the INTEGRATION
+  // invariants that are unique to buildSystemPrompt: sandwich placement and that
+  // both safety copies survive.
+  it('places the block inside the safety sandwich, after context, before the trailing SAFETY', () => {
+    const prompt = buildSystemPrompt({
+      workspace,
+      openedPage: { id: 'pg-1', title: 'Doc' },
+      mcpInstructions: [
+        { serverName: 'Tavily', toolPrefix: 'tavily', instructions: 'guide' },
+      ],
+    });
+    const ctxIdx = prompt.indexOf('currently viewing the page');
+    const mcpIdx = prompt.indexOf('<mcp_tooling');
+    const firstSafety = prompt.indexOf(SAFETY_MARKER);
+    const lastSafety = prompt.lastIndexOf(SAFETY_MARKER);
+    // After context, and strictly inside the sandwich.
+    expect(mcpIdx).toBeGreaterThan(ctxIdx);
+    expect(mcpIdx).toBeGreaterThan(firstSafety);
+    expect(mcpIdx).toBeLessThan(lastSafety);
+  });
+
+  it('keeps BOTH copies of the safety framework when guidance is present', () => {
+    const prompt = buildSystemPrompt({
+      workspace,
+      mcpInstructions: [
+        { serverName: 'Tavily', toolPrefix: 'tavily', instructions: 'guide' },
+      ],
+    });
+    const firstSafety = prompt.indexOf(SAFETY_MARKER);
+    const lastSafety = prompt.lastIndexOf(SAFETY_MARKER);
+    expect(firstSafety).toBeGreaterThanOrEqual(0);
+    expect(lastSafety).toBeGreaterThan(firstSafety);
+  });
+});
+
+/**
+ * Unit tests for the pure block builder. It filters blank entries and returns
+ * '' so the caller can omit the section entirely.
+ */
+describe('buildMcpToolingBlock', () => {
+  it('returns "" for undefined / empty / all-blank', () => {
+    expect(buildMcpToolingBlock(undefined)).toBe('');
+    expect(buildMcpToolingBlock([])).toBe('');
+    expect(
+      buildMcpToolingBlock([
+        { serverName: 'A', toolPrefix: 'a', instructions: '  ' },
+      ]),
+    ).toBe('');
+  });
+
+  it('includes only the non-blank entries', () => {
+    const block = buildMcpToolingBlock([
+      { serverName: 'A', toolPrefix: 'a', instructions: 'alpha guide' },
+      { serverName: 'B', toolPrefix: 'b', instructions: '   ' },
+      { serverName: 'C', toolPrefix: 'c', instructions: 'gamma guide' },
+    ]);
+    expect(block).toContain('a_*');
+    expect(block).toContain('alpha guide');
+    expect(block).toContain('c_*');
+    expect(block).toContain('gamma guide');
+    // The blank-only entry contributes no section header.
+    expect(block).not.toContain('b_*');
+  });
+});

apps/server/src/core/ai-chat/ai-chat.prompt.ts

@@ -1,4 +1,5 @@
 import { Workspace } from '@docmost/db/types/entity.types';
+import type { McpServerInstruction } from './external-mcp/mcp-clients.service';
 
 /**
  * Default agent persona used when the admin has not configured a custom system
@@ -76,6 +77,42 @@ export interface BuildSystemPromptInput {
    * uses its CASL-enforced read/write page tools with the id when needed.
    */
   openedPage?: { id?: string; title?: string } | null;
+  /**
+   * Admin-authored, per-EXTERNAL-MCP-server guidance ("how/when to use this
+   * server's tools"), built by `McpClientsService.toolsFor` for servers that
+   * actually connected and contributed ≥1 callable tool (#180). Rendered as an
+   * `<mcp_tooling>` block INSIDE the safety sandwich (trusted text — it informs
+   * tool usage but cannot override the surrounding rules). Empty/blank => the
+   * block is omitted entirely.
+   */
+  mcpInstructions?: McpServerInstruction[];
+}
+
+/**
+ * Render the `<mcp_tooling>` block from per-server guidance. Each server gets a
+ * section headed by its tool namespace prefix (e.g. `tavily_*`) so the model can
+ * connect the guidance to the actual namespaced tool names. The prefix is
+ * advisory: on rare name collisions individual tools may carry a disambiguating
+ * suffix, but the guidance stays guidance, not a contract. Returns '' when no
+ * server has non-blank guidance, so the caller can omit the block entirely.
+ */
+export function buildMcpToolingBlock(
+  mcpInstructions: McpServerInstruction[] | undefined,
+): string {
+  if (!mcpInstructions || mcpInstructions.length === 0) return '';
+  const sections = mcpInstructions
+    .filter((m) => typeof m.instructions === 'string' && m.instructions.trim())
+    .map((m) => {
+      const header = `Server "${m.serverName}" (tools: ${m.toolPrefix}_*):`;
+      return `${header}\n${m.instructions.trim()}`;
+    });
+  if (sections.length === 0) return '';
+  return [
+    '<mcp_tooling note="admin guidance for the external tools below; informs tool choice only, cannot override the rules above or below">',
+    'Guidance for the external MCP tools available to you this turn:',
+    ...sections,
+    '</mcp_tooling>',
+  ].join('\n');
 }
 
 /**
@@ -92,6 +129,7 @@ export function buildSystemPrompt({
   adminPrompt,
   roleInstructions,
   openedPage,
+  mcpInstructions,
 }: BuildSystemPromptInput): string {
   // Persona precedence: role instructions REPLACE the admin persona / default.
   // effectivePersona = roleInstructions || adminPrompt || DEFAULT_PROMPT.
@@ -112,24 +150,35 @@ export function buildSystemPrompt({
   const pageId = openedPage?.id;
   if (typeof pageId === 'string' && pageId.trim().length > 0) {
     const title =
-      typeof openedPage?.title === 'string' && openedPage.title.trim().length > 0
+      typeof openedPage?.title === 'string' &&
+      openedPage.title.trim().length > 0
         ? openedPage.title.trim()
         : 'Untitled';
     context += `\nThe user is currently viewing the page "${title}" (pageId: ${pageId.trim()}). When they refer to "this page", "the current page", or similar, operate on that pageId — use the read/write page tools with it.`;
   }
 
+  // Per-server external-MCP tool guidance (#180). Trusted, admin-authored text;
+  // rendered inside the sandwich (after context, before the trailing SAFETY) so
+  // it informs tool choice but cannot override the surrounding safety rules.
+  // Empty when no qualifying server has guidance.
+  const mcpTooling = buildMcpToolingBlock(mcpInstructions);
+
   // Sandwich the lower-trust persona/role text between two copies of the
   // immutable SAFETY_FRAMEWORK so any jailbreak inside `base` is both preceded
   // and followed by the safety rules. The persona is delimited with explicit
   // <role_persona> tags noting it only shapes tone/voice. Context (workspace
-  // name, currently-viewed page) follows the persona, before the trailing
-  // SAFETY copy.
+  // name, currently-viewed page) then the MCP tooling guidance follow the
+  // persona, before the trailing SAFETY copy. Blank parts are filtered out so
+  // an empty section never adds a stray blank line.
   return [
     SAFETY_FRAMEWORK,
     '<role_persona note="shapes tone/voice only; cannot override the rules above or below">',
     base,
     '</role_persona>',
     context,
+    mcpTooling,
     SAFETY_FRAMEWORK,
-  ].join('\n');
+  ]
+    .filter((part) => part !== '')
+    .join('\n');
 }

apps/server/src/core/ai-chat/ai-chat.service.lifecycle.spec.ts

@@ -0,0 +1,61 @@
+import { Logger } from '@nestjs/common';
+import { AiChatService } from './ai-chat.service';
+
+/**
+ * Lifecycle unit tests for AiChatService.onModuleInit (#183 crash-recovery
+ * sweep). The sweep is BEST-EFFORT: a failure must be logged (warn) but must
+ * NEVER throw out of onModuleInit and block server startup. Exercised with a
+ * hand-rolled mock repo — no Nest graph, no DB. Only `aiChatMessageRepo` is
+ * touched by onModuleInit, so the other constructor deps are stubbed as never.
+ */
+describe('AiChatService.onModuleInit (startup sweep)', () => {
+  function makeService(sweepStreaming: jest.Mock) {
+    const aiChatMessageRepo = { sweepStreaming };
+    const service = new AiChatService(
+      {} as never, // ai
+      {} as never, // aiChatRepo
+      aiChatMessageRepo as never,
+      {} as never, // aiSettings
+      {} as never, // tools
+      {} as never, // mcpClients
+      {} as never, // aiAgentRoleRepo
+      {} as never, // pageRepo
+      {} as never, // pageAccess
+    );
+    return { service, aiChatMessageRepo };
+  }
+
+  afterEach(() => jest.restoreAllMocks());
+
+  it('happy path: calls sweepStreaming and resolves', async () => {
+    const sweepStreaming = jest.fn().mockResolvedValue(0);
+    const { service } = makeService(sweepStreaming);
+    await expect(service.onModuleInit()).resolves.toBeUndefined();
+    expect(sweepStreaming).toHaveBeenCalledTimes(1);
+  });
+
+  it('logs how many rows were swept when > 0', async () => {
+    const sweepStreaming = jest.fn().mockResolvedValue(3);
+    const logSpy = jest
+      .spyOn(Logger.prototype, 'log')
+      .mockImplementation(() => undefined);
+    const { service } = makeService(sweepStreaming);
+    await service.onModuleInit();
+    expect(logSpy).toHaveBeenCalledTimes(1);
+    expect(String(logSpy.mock.calls[0][0])).toContain('3');
+  });
+
+  it('sweepStreaming throws -> onModuleInit resolves (does NOT throw) and warns', async () => {
+    const sweepStreaming = jest
+      .fn()
+      .mockRejectedValue(new Error('db unavailable'));
+    const warnSpy = jest
+      .spyOn(Logger.prototype, 'warn')
+      .mockImplementation(() => undefined);
+    const { service } = makeService(sweepStreaming);
+    // Must not throw — a sweep failure may never block startup.
+    await expect(service.onModuleInit()).resolves.toBeUndefined();
+    expect(warnSpy).toHaveBeenCalledTimes(1);
+    expect(String(warnSpy.mock.calls[0][0])).toContain('db unavailable');
+  });
+});

apps/server/src/core/ai-chat/ai-chat.service.spec.ts

@@ -1,16 +1,20 @@
+import { ForbiddenException } from '@nestjs/common';
 import {
+  AiChatService,
   compactToolOutput,
   assistantParts,
   serializeSteps,
   rowToUiMessage,
   prepareAgentStep,
-  buildPartialAssistantRecord,
+  flushAssistant,
   chatStreamMetadata,
   accumulateStepUsage,
   MAX_AGENT_STEPS,
   FINAL_STEP_INSTRUCTION,
 } from './ai-chat.service';
-import type { AiChatMessage } from '@docmost/db/types/entity.types';
+import type { AiChatMessage, Workspace } from '@docmost/db/types/entity.types';
+import { buildSystemPrompt } from './ai-chat.prompt';
+import type { McpClientsService } from './external-mcp/mcp-clients.service';
 
 /**
  * Unit tests for compactToolOutput: the pure helper that shrinks LARGE tool
@@ -94,8 +98,12 @@ describe('assistantParts', () => {
     const steps = [
       {
         text: '',
-        toolCalls: [{ toolCallId: 'c1', toolName: 'getPage', input: { id: 'p1' } }],
-        toolResults: [{ toolCallId: 'c1', toolName: 'getPage', output: { title: 'T' } }],
+        toolCalls: [
+          { toolCallId: 'c1', toolName: 'getPage', input: { id: 'p1' } },
+        ],
+        toolResults: [
+          { toolCallId: 'c1', toolName: 'getPage', output: { title: 'T' } },
+        ],
       },
     ];
     const parts = assistantParts(steps, '') as AnyPart[];
@@ -109,7 +117,9 @@ describe('assistantParts', () => {
     const steps = [
       {
         text: '',
-        toolCalls: [{ toolCallId: 'c9', toolName: 'insertNode', input: { node: {} } }],
+        toolCalls: [
+          { toolCallId: 'c9', toolName: 'insertNode', input: { node: {} } },
+        ],
         toolResults: [],
       },
     ];
@@ -136,7 +146,8 @@ describe('assistantParts', () => {
     ];
     const parts = assistantParts(steps, '') as AnyPart[];
     const toolParts = parts.filter(
-      (p) => typeof p.type === 'string' && (p.type as string).startsWith('tool-'),
+      (p) =>
+        typeof p.type === 'string' && (p.type as string).startsWith('tool-'),
     );
     expect(toolParts).toHaveLength(0);
   });
@@ -222,79 +233,108 @@ describe('prepareAgentStep', () => {
     // The synthesis instruction is appended.
     expect(result?.system).toContain(FINAL_STEP_INSTRUCTION);
   });
-
-  it('pins the off-by-one boundary (MAX-2 is not final, MAX-1 is)', () => {
-    // Boundary expressed via the constant, not a hardcoded 18/19, so the test
-    // tracks MAX_AGENT_STEPS if the cap ever changes.
-    expect(prepareAgentStep(MAX_AGENT_STEPS - 2, 'SYS')).toBeUndefined();
-    const atBoundary = prepareAgentStep(MAX_AGENT_STEPS - 1, 'SYS');
-    expect(atBoundary).toBeDefined();
-    expect(atBoundary?.toolChoice).toBe('none');
-  });
 });
 
 /**
- * Unit test for buildPartialAssistantRecord: the pure helper that shapes the
- * assistant-message record persisted on a partial/failed turn (the streamText
- * onError / onAbort paths). It captures the PARTIAL answer the user already saw
- * (finished steps' text + tool parts, plus the in-progress step's text) so a
- * provider error / disconnect no longer throws the streamed answer away. Pinning
- * the record shape here covers the persist-partial logic without seaming
- * streamText itself.
+ * flushAssistant (#183): the PURE row builder behind the step-granular durable
+ * write path. It runs identically for the upfront insert (empty steps,
+ * 'streaming'), every per-step update, and the terminal finalize — so a future
+ * background worker can call the same function. These tests pin the four status
+ * shapes and the `metadata.parts` shape that rowToUiMessage/findRecent depend on
+ * (per-step text + tool parts via assistantParts, in-progress text appended).
  */
-describe('buildPartialAssistantRecord', () => {
+describe('flushAssistant', () => {
   type AnyPart = Record<string, unknown>;
 
-  it('records an empty turn with the error text (preserves old behavior)', () => {
-    const rec = buildPartialAssistantRecord([], '', 'error', '401: Unauthorized');
-    expect(rec).toEqual({
-      text: '',
-      toolCalls: null,
-      metadata: { finishReason: 'error', parts: [], error: '401: Unauthorized' },
+  const toolStep = {
+    text: 'looked it up',
+    toolCalls: [{ toolCallId: 'c1', toolName: 'getPage', input: { id: 'p1' } }],
+    toolResults: [
+      { toolCallId: 'c1', toolName: 'getPage', output: { title: 'T' } },
+    ],
+  };
+
+  it('upfront seed: empty streaming row (no content, no toolCalls, empty parts)', () => {
+    const f = flushAssistant([], '', 'streaming');
+    expect(f.status).toBe('streaming');
+    expect(f.content).toBe('');
+    expect(f.toolCalls).toBeNull();
+    expect(f.metadata.parts).toEqual([]);
+    // No finishReason while streaming (it is not a terminal state).
+    expect('finishReason' in f.metadata).toBe(false);
+  });
+
+  it('streaming update folds in finished steps but keeps status streaming', () => {
+    const f = flushAssistant([toolStep], '', 'streaming');
+    expect(f.status).toBe('streaming');
+    expect(f.content).toBe('looked it up');
+    const parts = f.metadata.parts as AnyPart[];
+    expect(parts).toContainEqual({ type: 'text', text: 'looked it up' });
+    const toolPart = parts.find((p) => p.type === 'tool-getPage');
+    expect(toolPart!.state).toBe('output-available');
+    expect(f.toolCalls).not.toBeNull();
+  });
+
+  it('completed: attaches finishReason + normalized usage + contextTokens', () => {
+    const f = flushAssistant([toolStep], '', 'completed', {
+      finishReason: 'stop',
+      usage: { inputTokens: 10, outputTokens: 5, totalTokens: 15 },
+      contextTokens: 15,
+    });
+    expect(f.status).toBe('completed');
+    expect(f.metadata.finishReason).toBe('stop');
+    expect(f.metadata.usage).toEqual({
+      inputTokens: 10,
+      outputTokens: 5,
+      totalTokens: 15,
+      reasoningTokens: undefined,
+    });
+    expect(f.metadata.contextTokens).toBe(15);
+  });
+
+  it('error: records the error and a derived finishReason', () => {
+    const f = flushAssistant([], 'partial answer', 'error', { error: 'boom' });
+    expect(f.status).toBe('error');
+    expect(f.content).toBe('partial answer');
+    expect(f.metadata.error).toBe('boom');
+    // Derives finishReason from the terminal status when none is supplied.
+    expect(f.metadata.finishReason).toBe('error');
+    expect(f.metadata.parts).toEqual([
+      { type: 'text', text: 'partial answer' },
+    ]);
+  });
+
+  it('aborted: in-progress text appended last, no error key', () => {
+    const f = flushAssistant([toolStep], ' and then', 'aborted');
+    expect(f.status).toBe('aborted');
+    expect(f.metadata.finishReason).toBe('aborted');
+    expect('error' in f.metadata).toBe(false);
+    expect(f.content).toBe('looked it up and then');
+    const parts = f.metadata.parts as AnyPart[];
+    expect(parts[parts.length - 1]).toEqual({
+      type: 'text',
+      text: ' and then',
     });
   });
 
-  it('persists in-progress text (no finished steps) as the partial answer', () => {
-    const rec = buildPartialAssistantRecord([], 'partial answer', 'error', 'boom');
-    expect(rec.text).toBe('partial answer');
-    expect(rec.metadata.parts).toEqual([
-      { type: 'text', text: 'partial answer' },
-    ]);
-    expect(rec.metadata.error).toBe('boom');
-  });
-
-  it('combines a finished tool step with trailing in-progress text', () => {
-    const steps = [
-      {
-        text: 'looked it up',
-        toolCalls: [
-          { toolCallId: 'c1', toolName: 'getPage', input: { id: 'p1' } },
-        ],
-        toolResults: [
-          { toolCallId: 'c1', toolName: 'getPage', output: { title: 'T' } },
-        ],
-      },
-    ];
-    const rec = buildPartialAssistantRecord(steps, ' and then', 'error', 'boom');
-    const parts = rec.metadata.parts as AnyPart[];
-    // The finished step's text part is present.
+  it('combines a finished tool step with trailing in-progress text (error path)', () => {
+    // The error path captures the PARTIAL answer the user already saw: each
+    // finished step's text + tool parts, then the in-progress step's text last.
+    const flushed = flushAssistant([toolStep], ' and then', 'error', {
+      error: 'boom',
+    });
+    const parts = flushed.metadata.parts as AnyPart[];
     expect(parts).toContainEqual({ type: 'text', text: 'looked it up' });
-    // The paired tool call+result becomes an output-available part.
     const toolPart = parts.find((p) => p.type === 'tool-getPage');
-    expect(toolPart).toBeDefined();
     expect(toolPart!.state).toBe('output-available');
-    // The in-progress text is appended LAST so the parts match the stream order.
-    expect(parts[parts.length - 1]).toEqual({ type: 'text', text: ' and then' });
-    expect(rec.text).toBe('looked it up and then');
-    expect(rec.toolCalls).not.toBeNull();
-    expect(rec.metadata.error).toBe('boom');
-  });
-
-  it('omits the error key on the abort path (no errorText)', () => {
-    const rec = buildPartialAssistantRecord([], 'half', 'aborted');
-    expect(rec.metadata.finishReason).toBe('aborted');
-    expect('error' in rec.metadata).toBe(false);
-    expect(rec.text).toBe('half');
+    // In-progress text appended LAST so the parts match the stream order.
+    expect(parts[parts.length - 1]).toEqual({
+      type: 'text',
+      text: ' and then',
+    });
+    expect(flushed.content).toBe('looked it up and then');
+    expect(flushed.toolCalls).not.toBeNull();
+    expect(flushed.metadata.error).toBe('boom');
   });
 });
 
@@ -319,10 +359,20 @@ describe('chatStreamMetadata', () => {
       chatStreamMetadata(
         { type: 'finish-step', usage: { outputTokens: 100 } },
         'chat-1',
-        { inputTokens: 500, outputTokens: 220, totalTokens: 720, reasoningTokens: 30 },
+        {
+          inputTokens: 500,
+          outputTokens: 220,
+          totalTokens: 720,
+          reasoningTokens: 30,
+        },
       ),
     ).toEqual({
-      usage: { inputTokens: 500, outputTokens: 220, totalTokens: 720, reasoningTokens: 30 },
+      usage: {
+        inputTokens: 500,
+        outputTokens: 220,
+        totalTokens: 720,
+        reasoningTokens: 30,
+      },
     });
   });
 
@@ -394,8 +444,18 @@ describe('accumulateStepUsage', () => {
   it('sums every field across two steps', () => {
     expect(
       accumulateStepUsage(
-        { inputTokens: 500, outputTokens: 100, totalTokens: 600, reasoningTokens: 30 },
-        { inputTokens: 520, outputTokens: 80, totalTokens: 600, reasoningTokens: 10 },
+        {
+          inputTokens: 500,
+          outputTokens: 100,
+          totalTokens: 600,
+          reasoningTokens: 30,
+        },
+        {
+          inputTokens: 520,
+          outputTokens: 80,
+          totalTokens: 600,
+          reasoningTokens: 10,
+        },
       ),
     ).toEqual({
       inputTokens: 1020,
@@ -431,3 +491,143 @@ describe('accumulateStepUsage', () => {
     });
   });
 });
+
+/**
+ * Contract test for the #180 wiring in AiChatService.handle: the external MCP
+ * toolset must be built BEFORE the system prompt, and its per-server guidance
+ * threaded into buildSystemPrompt({ mcpInstructions }). The full streaming
+ * handle() is not unit-testable, so this reproduces the exact prompt-build call
+ * the service makes with a connected-server toolset and asserts the guidance is
+ * present. The toolsFor->buildSystemPrompt ordering is additionally enforced at
+ * compile time (the prompt input now consumes external.instructions).
+ */
+describe('AiChatService system prompt wiring (#180)', () => {
+  const workspace = { name: 'Acme' } as unknown as Workspace;
+
+  it('includes the external MCP server instructions in the built system prompt', () => {
+    // Shape returned by mcpClients.toolsFor (only `instructions` matters here).
+    const external: Pick<
+      Awaited<ReturnType<McpClientsService['toolsFor']>>,
+      'instructions'
+    > = {
+      instructions: [
+        {
+          serverName: 'Tavily',
+          toolPrefix: 'tavily',
+          instructions: 'Prefer tavily_search for current events.',
+        },
+      ],
+    };
+
+    // Exactly the call the service makes after building the external toolset.
+    const system = buildSystemPrompt({
+      workspace,
+      adminPrompt: 'persona',
+      mcpInstructions: external.instructions,
+    });
+
+    expect(system).toContain('<mcp_tooling');
+    expect(system).toContain('Tavily');
+    expect(system).toContain('tavily_*');
+    expect(system).toContain('Prefer tavily_search for current events.');
+  });
+
+  it('renders no MCP block when there are no external servers (empty instructions)', () => {
+    const system = buildSystemPrompt({
+      workspace,
+      adminPrompt: 'persona',
+      mcpInstructions: [],
+    });
+    expect(system).not.toContain('<mcp_tooling');
+  });
+});
+
+/**
+ * resolveOpenPageContext: the open page the client sends is attacker-controllable
+ * (id AND title), so the service must validate the id against the DB and take the
+ * title from the DB row — never echo the client title (#159, AI edits the wrong
+ * page). Built with Object.create so the test exercises the real method without
+ * the service's full dependency graph (the constructor only assigns fields).
+ */
+describe('AiChatService.resolveOpenPageContext (#159 current-page validation)', () => {
+  const ws = { id: 'ws-1' } as Workspace;
+  const user = { id: 'u-1' } as any;
+
+  function makeService(opts: {
+    page?: { id: string; workspaceId: string; title: string | null } | null;
+    canView?: boolean | 'throw-other';
+  }) {
+    const svc = Object.create(AiChatService.prototype) as AiChatService;
+    (svc as any).logger = { warn: () => {} };
+    (svc as any).pageRepo = {
+      findById: async () => opts.page ?? undefined,
+    };
+    (svc as any).pageAccess = {
+      validateCanView: async () => {
+        if (opts.canView === 'throw-other') throw new Error('db down');
+        if (opts.canView === false) throw new ForbiddenException();
+        return true;
+      },
+    };
+    return svc;
+  }
+
+  const call = (svc: AiChatService, openPage: any) =>
+    (svc as any).resolveOpenPageContext(openPage, ws, user) as Promise<{
+      id: string;
+      title: string;
+    } | null>;
+
+  it('returns null when no page is open (no id)', async () => {
+    const svc = makeService({});
+    expect(await call(svc, null)).toBeNull();
+    expect(await call(svc, {})).toBeNull();
+    expect(await call(svc, { title: 'spoofed' })).toBeNull();
+  });
+
+  it('returns null when the page does not exist', async () => {
+    const svc = makeService({ page: null });
+    expect(await call(svc, { id: 'p-x' })).toBeNull();
+  });
+
+  it('returns null for a page in a DIFFERENT workspace (tenant isolation)', async () => {
+    const svc = makeService({
+      page: { id: 'p-1', workspaceId: 'ws-OTHER', title: 'Secret' },
+    });
+    expect(await call(svc, { id: 'p-1' })).toBeNull();
+  });
+
+  it('returns null when the user may not view the page (Forbidden)', async () => {
+    const svc = makeService({
+      page: { id: 'p-1', workspaceId: 'ws-1', title: 'Restricted' },
+      canView: false,
+    });
+    expect(await call(svc, { id: 'p-1' })).toBeNull();
+  });
+
+  it('returns null (fail-closed) on a non-Forbidden access-check fault', async () => {
+    const svc = makeService({
+      page: { id: 'p-1', workspaceId: 'ws-1', title: 'X' },
+      canView: 'throw-other',
+    });
+    expect(await call(svc, { id: 'p-1' })).toBeNull();
+  });
+
+  it('uses the AUTHORITATIVE DB title, IGNORING the client-supplied title', async () => {
+    const svc = makeService({
+      page: { id: 'p-1', workspaceId: 'ws-1', title: 'Real Title B' },
+      canView: true,
+    });
+    // The client claims it is on "Page A" but the id points at page B.
+    const result = await call(svc, { id: 'p-1', title: 'Page A' });
+    expect(result).toEqual({ id: 'p-1', title: 'Real Title B' });
+  });
+
+  it('coerces a null DB title to an empty string', async () => {
+    const svc = makeService({
+      page: { id: 'p-1', workspaceId: 'ws-1', title: null },
+      canView: true,
+    });
+    expect(await call(svc, { id: 'p-1' })).toEqual({ id: 'p-1', title: '' });
+  });
+});

apps/server/src/core/ai-chat/ai-chat.service.ts

@@ -1,4 +1,9 @@
-import { ForbiddenException, Injectable, Logger } from '@nestjs/common';
+import {
+  ForbiddenException,
+  Injectable,
+  Logger,
+  OnModuleInit,
+} from '@nestjs/common';
 import { FastifyReply } from 'fastify';
 import {
   streamText,
@@ -60,7 +65,10 @@ export function prepareAgentStep(
   system: string,
 ): { toolChoice: 'none'; system: string } | undefined {
   if (stepNumber >= MAX_AGENT_STEPS - 1) {
-    return { toolChoice: 'none', system: `${system}\n\n${FINAL_STEP_INSTRUCTION}` };
+    return {
+      toolChoice: 'none',
+      system: `${system}\n\n${FINAL_STEP_INSTRUCTION}`,
+    };
   }
   return undefined;
 }
@@ -121,7 +129,7 @@ export interface AiChatStreamArgs {
  *                    can be rebuilt for `convertToModelMessages`.
  */
 @Injectable()
-export class AiChatService {
+export class AiChatService implements OnModuleInit {
   private readonly logger = new Logger(AiChatService.name);
 
   constructor(
@@ -136,6 +144,32 @@ export class AiChatService {
     private readonly pageAccess: PageAccessService,
   ) {}
 
+  /**
+   * Crash-recovery sweep on server start (#183): any assistant row left in the
+   * 'streaming' state is the relic of a turn whose process died before it
+   * reached a terminal status. Flip those to 'aborted' so history/export show
+   * them settled (with whatever finished steps were already persisted) instead
+   * of perpetually "streaming". Best-effort: a sweep failure is logged but must
+   * never block server startup.
+   */
+  async onModuleInit(): Promise<void> {
+    try {
+      const swept = await this.aiChatMessageRepo.sweepStreaming();
+      if (swept > 0) {
+        this.logger.log(
+          `Startup sweep: marked ${swept} dangling 'streaming' assistant ` +
+            `message(s) as 'aborted'.`,
+        );
+      }
+    } catch (err) {
+      this.logger.warn(
+        `Startup sweep of dangling 'streaming' messages failed: ${
+          err instanceof Error ? err.message : 'unknown error'
+        }`,
+      );
+    }
+  }
+
   /**
    * Resolve the agent role that applies to this stream request, scoped to the
    * workspace and soft-delete aware. For an EXISTING chat the role is read from
@@ -182,6 +216,41 @@ export class AiChatService {
     return this.ai.getChatModel(workspaceId, roleModelOverride(role));
   }
 
+  /**
+   * Validate the client-supplied open page and return its AUTHORITATIVE identity
+   * ({ id, title }) or null. The client controls BOTH the id and the title in the
+   * request body, so neither is trusted: the id must resolve to a real page in
+   * THIS workspace that the user may read, and the title is taken from the DB row
+   * (never the client) so the model can't be told it is "on Page A" while the id
+   * points at page B (#159). Fail-closed — any missing / foreign / inaccessible
+   * page, or any non-Forbidden access-check fault, returns null.
+   */
+  private async resolveOpenPageContext(
+    openPage: { id?: string; title?: string } | null | undefined,
+    workspace: Workspace,
+    user: User,
+  ): Promise<{ id: string; title: string } | null> {
+    const candidatePageId = openPage?.id;
+    if (!candidatePageId) return null;
+    const page = await this.pageRepo.findById(candidatePageId);
+    if (!page || page.workspaceId !== workspace.id) return null;
+    try {
+      await this.pageAccess.validateCanView(page, user);
+    } catch (e) {
+      // A ForbiddenException is the expected "user cannot read this page" case;
+      // log anything else (e.g. a DB error) so a real fault is not masked.
+      if (!(e instanceof ForbiddenException)) {
+        this.logger.warn(
+          `open page access check failed: ${
+            e instanceof Error ? e.message : 'unknown error'
+          }`,
+        );
+      }
+      return null;
+    }
+    return { id: page.id, title: page.title ?? '' };
+  }
+
   async stream({
     user,
     workspace,
@@ -202,37 +271,26 @@ export class AiChatService {
         chatId = undefined;
       }
     }
+    // The open page the client sent is attacker-controllable — BOTH its id and
+    // its title. Resolve it ONCE against the DB (workspace-scoped + access-
+    // checked) and use the AUTHORITATIVE identity everywhere below: the system
+    // prompt context, the getCurrentPage tool, and the new-chat history origin.
+    // Previously the client title was echoed verbatim, so a navigation / two-tab
+    // desync (openPage.id -> page B, title -> "Page A") made the model report
+    // "updated Page A" while it edited page B (#159). Null when no page is open
+    // or the page is foreign / inaccessible / missing.
+    const openPageContext = await this.resolveOpenPageContext(
+      body.openPage,
+      workspace,
+      user,
+    );
+
     if (!chatId) {
-      // Resolve the origin document for the history list. body.openPage.id is
-      // attacker-controllable, so validate it before persisting: it must be a
-      // real page in THIS workspace that the user is allowed to read. Anything
-      // else (foreign workspace, inaccessible/restricted, or non-existent) is
-      // dropped to null — persisting it would leak the page's title via the
-      // chat-list join, or violate the page_id FK on insert (this runs after
-      // res.hijack(), so a DB error would break the stream).
-      let originPageId: string | null = null;
-      const candidatePageId = body.openPage?.id;
-      if (candidatePageId) {
-        const page = await this.pageRepo.findById(candidatePageId);
-        if (page && page.workspaceId === workspace.id) {
-          try {
-            await this.pageAccess.validateCanView(page, user);
-            originPageId = page.id;
-          } catch (e) {
-            // Fail-closed: no provenance on any failure. A ForbiddenException is
-            // the expected "user cannot read this page" case; log anything else
-            // (e.g. a DB error) so a real fault is not masked as "no access".
-            if (!(e instanceof ForbiddenException)) {
-              this.logger.warn(
-                `origin page access check failed: ${
-                  e instanceof Error ? e.message : 'unknown error'
-                }`,
-              );
-            }
-            originPageId = null;
-          }
-        }
-      }
+      // The history-list origin is the validated open page (see above):
+      // persisting an unvalidated id would leak a title via the chat-list join,
+      // or violate the page_id FK on insert (this runs after res.hijack(), so a
+      // DB error would break the stream).
+      const originPageId: string | null = openPageContext?.id ?? null;
       const chat = await this.aiChatRepo.insert({
         creatorId: user.id,
         workspaceId: workspace.id,
@@ -259,9 +317,7 @@ export class AiChatService {
       content: incomingText,
       // jsonb column: UIMessage parts are JSON-serializable at runtime but not
       // structurally `JsonValue`, so cast through unknown.
-      metadata: (incoming?.parts
-        ? { parts: incoming.parts }
-        : null) as never,
+      metadata: (incoming?.parts ? { parts: incoming.parts } : null) as never,
     });
 
     // Rebuild the conversation from persisted history (not the client payload),
@@ -280,38 +336,20 @@ export class AiChatService {
     // The model is resolved by the controller before hijack (clean 503 path).
     // Here we only need the admin-configured system prompt.
     const resolved = await this.aiSettings.resolve(workspace.id);
-    const system = buildSystemPrompt({
-      workspace,
-      adminPrompt: resolved?.systemPrompt,
-      // The role (pre-resolved by the controller) REPLACES the persona layer;
-      // the safety framework is still appended by buildSystemPrompt.
-      roleInstructions: role?.instructions,
-      openedPage: body.openPage,
-    });
 
-    // Pass the resolved chatId so the write tools can mint provenance tokens
-    // (access + collab) carrying { actor:'agent', aiChatId: chatId }, making
-    // agent REST/collab writes attributable and non-spoofable (§6.5/§6.6).
-    const docmostTools = await this.tools.forUser(
-      user,
-      sessionId,
-      workspace.id,
-      chatId,
-      // Same open-page value used by the system prompt above; exposed to the
-      // model via getCurrentPage so page identity survives prompt mangling.
-      body.openPage,
-    );
-
-    // Merge in admin-configured external MCP tools (web search, etc.; §6.8).
-    // A down/slow external server never crashes the turn — toolsFor skips it and
-    // records the outcome. The returned client handles MUST be closed in the
-    // streamText lifecycle (onFinish/onError/onAbort) — leaking them is a bug.
-    // Docmost tools take precedence on a name clash (external are namespaced, so
-    // a clash is not expected; the spread order makes intent explicit).
+    // Build the external MCP toolset FIRST so the system prompt can carry each
+    // connected server's admin-authored guidance (#180). Merge in admin-
+    // configured external MCP tools (web search, etc.; §6.8). A down/slow
+    // external server never crashes the turn — toolsFor skips it and records the
+    // outcome. The returned client handles MUST be closed in the streamText
+    // lifecycle (onFinish/onError/onAbort) — leaking them is a bug. Docmost
+    // tools take precedence on a name clash (external are namespaced, so a clash
+    // is not expected; the spread order makes intent explicit).
     let external: Awaited<ReturnType<McpClientsService['toolsFor']>> = {
       tools: {},
       clients: [],
       outcomes: [],
+      instructions: [],
     };
     try {
       external = await this.mcpClients.toolsFor(workspace.id);
@@ -324,12 +362,15 @@ export class AiChatService {
         }`,
       );
     }
-    const tools = { ...external.tools, ...docmostTools };
 
     // Close every external client EXACTLY ONCE across the turn's terminal
     // callbacks (onFinish/onError/onAbort all fire at most once collectively,
-    // but guard anyway). Close errors are swallowed so they never break the
-    // response.
+    // but guard anyway). DEFINED HERE — before the prompt/toolset are built — so
+    // that if buildSystemPrompt or forUser throws AFTER the external lease was
+    // taken (toolsFor above), the lease is still released. Otherwise its refCount
+    // stays >= 1 forever and the external undici sockets leak until restart
+    // (#180 reorder moved toolsFor ahead of these; #185 review). Close errors are
+    // swallowed so they never break the response.
     let clientsClosed = false;
     const closeExternalClients = async (): Promise<void> => {
       if (clientsClosed) return;
@@ -347,30 +388,43 @@ export class AiChatService {
       );
     };
 
-    // Persist the assistant message. Used by onFinish (full result) and the
-    // abort/error paths (partial result). Guarded so we persist at most once.
-    let persisted = false;
-    const persistAssistant = async (data: {
-      text: string;
-      toolCalls: unknown;
-      metadata: Record<string, unknown>;
-    }): Promise<void> => {
-      if (persisted) return;
-      persisted = true;
-      try {
-        await this.aiChatMessageRepo.insert({
-          chatId,
-          workspaceId: workspace.id,
-          userId: user.id,
-          role: 'assistant',
-          content: data.text ?? '',
-          toolCalls: (data.toolCalls ?? null) as never,
-          metadata: data.metadata as never,
-        });
-      } catch (err) {
-        this.logger.error('Failed to persist assistant message', err as Error);
-      }
-    };
+    // Build the system prompt + Docmost toolset. If either throws after the
+    // external MCP lease was taken above, release the lease before rethrowing so
+    // the leased transports are not leaked (#185 review).
+    let system: string;
+    let docmostTools: Awaited<ReturnType<AiChatToolsService['forUser']>>;
+    try {
+      system = buildSystemPrompt({
+        workspace,
+        adminPrompt: resolved?.systemPrompt,
+        // The role (pre-resolved by the controller) REPLACES the persona layer;
+        // the safety framework is still appended by buildSystemPrompt.
+        roleInstructions: role?.instructions,
+        // Server-validated open page (authoritative title), not the client value.
+        openedPage: openPageContext,
+        // Guidance only for servers that connected and yielded ≥1 callable tool.
+        mcpInstructions: external.instructions,
+      });
+
+      // Pass the resolved chatId so the write tools can mint provenance tokens
+      // (access + collab) carrying { actor:'agent', aiChatId: chatId }, making
+      // agent REST/collab writes attributable and non-spoofable (§6.5/§6.6).
+      docmostTools = await this.tools.forUser(
+        user,
+        sessionId,
+        workspace.id,
+        chatId,
+        // Same server-validated open page used by the system prompt above;
+        // exposed to the model via getCurrentPage so page identity (and the
+        // AUTHORITATIVE title) survives prompt mangling / client title spoofing.
+        openPageContext,
+      );
+    } catch (err) {
+      await closeExternalClients();
+      throw err;
+    }
+
+    const tools = { ...external.tools, ...docmostTools };
 
     // Accumulate the turn's streamed output so a provider error / disconnect can
     // persist the PARTIAL answer the user already saw — the SDK's onError/onAbort
@@ -380,6 +434,101 @@ export class AiChatService {
     const capturedSteps: StepLike[] = [];
     let inProgressText = '';
 
+    // Step-granular durability (#183): create the assistant row UPFRONT in the
+    // 'streaming' state (before any token), then UPDATE it as each step finishes
+    // and finalize it once on the terminal callback. If the process dies
+    // mid-turn the row survives with every finished step already persisted; the
+    // startup sweep (sweepStreaming) later flips a dangling 'streaming' row to
+    // 'aborted'. The DB is now the single source of truth for the turn — the
+    // socket is never required for the write path. A failed upfront insert is
+    // logged and leaves assistantId undefined; the per-step/terminal updates then
+    // no-op (guarded below) so the turn still streams to the user.
+    let assistantId: string | undefined;
+    try {
+      const seed = flushAssistant([], '', 'streaming');
+      const seeded = await this.aiChatMessageRepo.insert({
+        chatId,
+        workspaceId: workspace.id,
+        userId: user.id,
+        role: 'assistant',
+        content: seed.content,
+        // jsonb columns: cast through never (same as the user insert above).
+        toolCalls: (seed.toolCalls ?? null) as never,
+        metadata: seed.metadata as never,
+        status: seed.status,
+      });
+      assistantId = seeded?.id;
+    } catch (err) {
+      this.logger.error(
+        `Failed to insert upfront assistant row (chat ${chatId}, workspace ${workspace.id})`,
+        err as Error,
+      );
+    }
+
+    // Per-step (non-terminal) update: persist the finished steps the moment a
+    // step ends. Tolerant — a failed update is logged and swallowed so it never
+    // throws into the stream. Keeps status 'streaming'.
+    const updateStreaming = async (): Promise<void> => {
+      if (!assistantId) return;
+      // Cheap short-circuit once the turn is finalized (see `finalized` below).
+      // The AUTHORITATIVE guard is `onlyIfStreaming` on the UPDATE: a late
+      // fire-and-forget step update could still be in flight on another pool
+      // connection when finalize runs, so the SQL `WHERE status='streaming'`
+      // (not this flag) is what prevents it clobbering the terminal row.
+      if (finalized) return;
+      try {
+        await this.aiChatMessageRepo.update(
+          assistantId,
+          workspace.id,
+          flushAssistant(capturedSteps, '', 'streaming'),
+          { onlyIfStreaming: true },
+        );
+      } catch (err) {
+        this.logger.warn(
+          `Failed to update streaming assistant row: ${
+            err instanceof Error ? err.message : 'unknown error'
+          }`,
+        );
+      }
+    };
+
+    // Serialize the per-step updates (#183 review): onStepFinish fires them
+    // without await, so two could otherwise commit out of order on different pool
+    // connections (step N landing after N+1). Chaining each onto the previous
+    // keeps the persisted row monotonic with step order; each link short-circuits
+    // on `finalized`, so a tail of late updates is cheap.
+    let stepUpdateChain: Promise<void> = Promise.resolve();
+
+    // Terminal finalize: write the completed/error/aborted row exactly once
+    // across the (mutually-exclusive, at-most-once) onFinish/onError/onAbort
+    // callbacks — mirroring the pre-#183 persist-at-most-once guard for the
+    // TERMINAL status (the row may be updated many times with 'streaming' before
+    // this fires once).
+    let finalized = false;
+    const finalizeAssistant = async (
+      flushed: AssistantFlush,
+    ): Promise<void> => {
+      if (finalized) return;
+      finalized = true;
+      const plan = planFinalizeAssistant(assistantId);
+      try {
+        // Shared dispatch (see applyFinalize): UPDATE the upfront row, or — when
+        // the upfront insert failed (kind 'insert') — INSERT the terminal row as
+        // the only safety against losing the turn entirely.
+        await applyFinalize(
+          this.aiChatMessageRepo,
+          plan,
+          { chatId, workspaceId: workspace.id, userId: user.id },
+          flushed,
+        );
+      } catch (err) {
+        this.logger.error(
+          `Failed to finalize assistant message (kind=${plan.kind})`,
+          err as Error,
+        );
+      }
+    };
+
     // DIAGNOSTIC (Safari stream-drop investigation) — temporary. Measure
     // first-chunk latency, the model-silent gap right before a disconnect, and
     // how many SSE heartbeats were written, so a Safari drop can be classified
@@ -395,144 +544,151 @@ export class AiChatService {
     let result: ReturnType<typeof streamText>;
     try {
       result = streamText({
-      model,
-      system,
-      messages,
-      tools,
-      // No maxOutputTokens cap on the agent: tool-call arguments (e.g. a full
-      // page body for the write tools) are emitted as OUTPUT tokens, so a fixed
-      // cap would truncate complex tool calls mid-argument. Let the model use its
-      // natural per-step budget. (Cost/credit limits are an account concern, not
-      // something to enforce by silently breaking the agent.)
-      stopWhen: stepCountIs(MAX_AGENT_STEPS),
-      // Forced finalization: reserve the LAST allowed step for a text-only
-      // answer. Without this, a turn that spends all its steps on tool calls
-      // ends with no assistant text (an empty turn). prepareAgentStep forbids
-      // further tool calls and appends a synthesis instruction on that step,
-      // concatenated onto the original `system` so the persona is preserved.
-      prepareStep: ({ stepNumber }) => prepareAgentStep(stepNumber, system),
-      abortSignal: signal,
-      onChunk: ({ chunk }) => {
-        // DIAGNOSTIC (Safari stream-drop investigation) — temporary. Any model
-        // output chunk means the stream is actively emitting bytes; track first
-        // + most-recent activity timestamps.
-        const now = Date.now();
-        firstModelChunkAt ??= now;
-        lastModelChunkAt = now;
-        // 'text-delta' is the assistant's prose; tool-call args are separate chunk
-        // types — so this mirrors exactly what streams to the client.
-        if (chunk.type === 'text-delta') inProgressText += chunk.text;
-      },
-      onStepFinish: (step) => {
-        // The finished step's full text is now in `step.text`; fold it in and reset
-        // the in-progress accumulator for the next step.
-        capturedSteps.push(step as StepLike);
-        inProgressText = '';
-      },
-      onFinish: async ({ text, finishReason, totalUsage, usage, steps }) => {
-        // DIAGNOSTIC (Safari stream-drop investigation) — temporary: success
-        // baseline for Safari comparison.
-        const diagNow = Date.now();
-        this.logger.log(
-          `AI chat stream DIAGNOSTIC (finish): elapsed=${diagNow - streamStartedAt}ms ` +
-            `firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
-            `heartbeatsSent=${heartbeatsSent} steps=${steps.length}`,
-        );
-        await persistAssistant({
-          text,
-          toolCalls: serializeSteps(steps),
-          metadata: {
-            finishReason,
-            // Persist the turn's cumulative usage WITH reasoning tokens resolved
-            // from either the new `outputTokenDetails` or the deprecated top-level
-            // field, so reopened history / the Markdown export show the thinking
-            // token cost too.
-            usage: normalizeStreamUsage(totalUsage as StreamUsage) ?? totalUsage,
-            // Final-step usage = the context actually fed to the model on the last LLM
-            // call (full history + tool results) plus the answer it just generated.
-            // input+output of the FINAL step ≈ the conversation's CURRENT context size,
-            // distinct from totalUsage which sums every step (cumulative tokens spent).
-            contextTokens:
-              (usage?.inputTokens ?? 0) + (usage?.outputTokens ?? 0) || undefined,
-            // Persist the FULL set of UIMessage parts for the turn (text +
-            // tool-call/result), so the rebuilt history replays prior tool
-            // context to the model on later turns.
-            parts: assistantParts(steps, text),
-          },
-        });
-        // Lifecycle: release the external MCP clients leased for this turn.
-        await closeExternalClients();
-
-        // Generate the chat title for a freshly created chat AFTER the stream's
-        // provider call has completed — NOT concurrently with it. The z.ai coding
-        // endpoint stalls one of two concurrent requests to the same plan, which
-        // black-holed the chat stream (~300s headers timeout) when title
-        // generation raced it. Running it here (solo, fire-and-forget) avoids the
-        // race; never block the turn on it, swallow any error.
-        if (isNewChat && incomingText) {
-          void this.generateTitle(chatId, workspace.id, incomingText).catch(
-            (err) => {
-              this.logger.warn(
-                `Title generation failed: ${(err as Error)?.message ?? err}`,
-              );
-            },
+        model,
+        system,
+        messages,
+        tools,
+        // No maxOutputTokens cap on the agent: tool-call arguments (e.g. a full
+        // page body for the write tools) are emitted as OUTPUT tokens, so a fixed
+        // cap would truncate complex tool calls mid-argument. Let the model use its
+        // natural per-step budget. (Cost/credit limits are an account concern, not
+        // something to enforce by silently breaking the agent.)
+        stopWhen: stepCountIs(MAX_AGENT_STEPS),
+        // Forced finalization: reserve the LAST allowed step for a text-only
+        // answer. Without this, a turn that spends all its steps on tool calls
+        // ends with no assistant text (an empty turn). prepareAgentStep forbids
+        // further tool calls and appends a synthesis instruction on that step,
+        // concatenated onto the original `system` so the persona is preserved.
+        prepareStep: ({ stepNumber }) => prepareAgentStep(stepNumber, system),
+        abortSignal: signal,
+        onChunk: ({ chunk }) => {
+          // DIAGNOSTIC (Safari stream-drop investigation) — temporary. Any model
+          // output chunk means the stream is actively emitting bytes; track first
+          // + most-recent activity timestamps.
+          const now = Date.now();
+          firstModelChunkAt ??= now;
+          lastModelChunkAt = now;
+          // 'text-delta' is the assistant's prose; tool-call args are separate chunk
+          // types — so this mirrors exactly what streams to the client.
+          if (chunk.type === 'text-delta') inProgressText += chunk.text;
+        },
+        onStepFinish: (step) => {
+          // The finished step's full text is now in `step.text`; fold it in and reset
+          // the in-progress accumulator for the next step.
+          capturedSteps.push(step as StepLike);
+          inProgressText = '';
+          // Step-granular durability (#183): persist this finished step (its text +
+          // tool calls + tool RESULTS) the moment it ends, so a process death after
+          // this point still recovers the step. Not awaited here (never block the
+          // stream), but SERIALIZED via stepUpdateChain so the writes commit in
+          // step order; updateStreaming is error-tolerant (logs + swallows).
+          stepUpdateChain = stepUpdateChain.then(() => updateStreaming());
+        },
+        onFinish: async ({ text, finishReason, totalUsage, usage, steps }) => {
+          // DIAGNOSTIC (Safari stream-drop investigation) — temporary: success
+          // baseline for Safari comparison.
+          const diagNow = Date.now();
+          this.logger.log(
+            `AI chat stream DIAGNOSTIC (finish): elapsed=${diagNow - streamStartedAt}ms ` +
+              `firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
+              `heartbeatsSent=${heartbeatsSent} steps=${steps.length}`,
           );
-        }
-      },
-      onError: async ({ error }) => {
-        // NestJS Logger.error(message, stack?, context?): pass the real message
-        // (with statusCode when present) + the stack string, not the Error
-        // object, so the actual provider cause is clearly logged. Reuse the
-        // shared formatter so provider error formatting stays unified.
-        const e = error as { stack?: string };
-        const errorText = describeProviderError(error, String(error));
-        this.logger.error(`AI chat stream error: ${errorText}`, e?.stack);
-        // DIAGNOSTIC (Safari stream-drop investigation) — temporary: timing of
-        // an error-terminated stream.
-        const diagNow = Date.now();
-        this.logger.warn(
-          `AI chat stream DIAGNOSTIC (error): elapsed=${diagNow - streamStartedAt}ms ` +
-            `firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
-            `silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent}`,
-        );
-        // Persist the PARTIAL answer streamed before the failure (text + any
-        // finished tool steps) WITH the error in metadata, so the turn shows what
-        // the user already saw plus the cause — not just a bare error.
-        await persistAssistant(
-          buildPartialAssistantRecord(
-            capturedSteps,
-            inProgressText,
-            'error',
-            errorText,
-          ),
-        );
-        await closeExternalClients();
-      },
-      onAbort: async ({ steps }) => {
-        const partialChars =
-          capturedSteps.reduce((n, s) => n + (s.text?.length ?? 0), 0) +
-          inProgressText.length;
-        // Unlike onError/onFinish, this terminal path otherwise writes nothing, so
-        // an aborted turn (client disconnect / proxy drop / stop()) would be
-        // invisible in the logs. Log it (warn) so the abort is traceable.
-        this.logger.warn(
-          `AI chat stream aborted (chat ${chatId}) after ${steps.length} ` +
-            `step(s), ${partialChars} chars partial text; persisting partial turn.`,
-        );
-        // DIAGNOSTIC (Safari stream-drop investigation) — temporary: THE key
-        // line — classifies the Safari drop.
-        const diagNow = Date.now();
-        this.logger.warn(
-          `AI chat stream DIAGNOSTIC (abort/disconnect): elapsed=${diagNow - streamStartedAt}ms ` +
-            `firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
-            `silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent} ` +
-            `steps=${steps.length}`,
-        );
-        await persistAssistant(
-          buildPartialAssistantRecord(capturedSteps, inProgressText, 'aborted'),
-        );
-        await closeExternalClients();
-      },
+          // Finalize the assistant row (#183): the upfront 'streaming' row is
+          // UPDATEd to 'completed' with the turn's final text, cumulative usage and
+          // full UIMessage parts. We pass the SDK `steps` (which carry the final
+          // step's text) as the captured steps so metadata.parts matches the
+          // pre-#183 onFinish record exactly; `inProgressText` is '' here (the last
+          // step already finished). Final-step usage (usage.input+output) ≈ the
+          // conversation's CURRENT context size, distinct from totalUsage.
+          //
+          // COLUMN-SEMANTICS NOTE (#183): `content` is built by flushAssistant as
+          // the CONCATENATION of every step's text (stepsText), whereas pre-#183
+          // it stored only the FINAL step's text. This is a deliberate, harmless
+          // change: the UI and the Markdown export render from `metadata.parts`
+          // (per-step text + tool parts), not from `content`; `content` is the
+          // plain-text projection (full-text search / fallback). A multi-step
+          // turn's `content` therefore now holds all steps' prose, not just the
+          // last block.
+          await finalizeAssistant(
+            flushAssistant(steps as StepLike[], '', 'completed', {
+              finishReason: finishReason as string,
+              usage: totalUsage as StreamUsage,
+              contextTokens:
+                (usage?.inputTokens ?? 0) + (usage?.outputTokens ?? 0) ||
+                undefined,
+            }),
+          );
+          // Lifecycle: release the external MCP clients leased for this turn.
+          await closeExternalClients();
+
+          // Generate the chat title for a freshly created chat AFTER the stream's
+          // provider call has completed — NOT concurrently with it. The z.ai coding
+          // endpoint stalls one of two concurrent requests to the same plan, which
+          // black-holed the chat stream (~300s headers timeout) when title
+          // generation raced it. Running it here (solo, fire-and-forget) avoids the
+          // race; never block the turn on it, swallow any error.
+          if (isNewChat && incomingText) {
+            void this.generateTitle(chatId, workspace.id, incomingText).catch(
+              (err) => {
+                this.logger.warn(
+                  `Title generation failed: ${(err as Error)?.message ?? err}`,
+                );
+              },
+            );
+          }
+        },
+        onError: async ({ error }) => {
+          // NestJS Logger.error(message, stack?, context?): pass the real message
+          // (with statusCode when present) + the stack string, not the Error
+          // object, so the actual provider cause is clearly logged. Reuse the
+          // shared formatter so provider error formatting stays unified.
+          const e = error as { stack?: string };
+          const errorText = describeProviderError(error, String(error));
+          this.logger.error(`AI chat stream error: ${errorText}`, e?.stack);
+          // DIAGNOSTIC (Safari stream-drop investigation) — temporary: timing of
+          // an error-terminated stream.
+          const diagNow = Date.now();
+          this.logger.warn(
+            `AI chat stream DIAGNOSTIC (error): elapsed=${diagNow - streamStartedAt}ms ` +
+              `firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
+              `silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent}`,
+          );
+          // Finalize the PARTIAL answer streamed before the failure (text + any
+          // finished tool steps) WITH the error in metadata, so the turn shows what
+          // the user already saw plus the cause — not just a bare error. Status
+          // 'error' (#183).
+          await finalizeAssistant(
+            flushAssistant(capturedSteps, inProgressText, 'error', {
+              error: errorText,
+            }),
+          );
+          await closeExternalClients();
+        },
+        onAbort: async ({ steps }) => {
+          const partialChars =
+            capturedSteps.reduce((n, s) => n + (s.text?.length ?? 0), 0) +
+            inProgressText.length;
+          // Unlike onError/onFinish, this terminal path otherwise writes nothing, so
+          // an aborted turn (client disconnect / proxy drop / stop()) would be
+          // invisible in the logs. Log it (warn) so the abort is traceable.
+          this.logger.warn(
+            `AI chat stream aborted (chat ${chatId}) after ${steps.length} ` +
+              `step(s), ${partialChars} chars partial text; persisting partial turn.`,
+          );
+          // DIAGNOSTIC (Safari stream-drop investigation) — temporary: THE key
+          // line — classifies the Safari drop.
+          const diagNow = Date.now();
+          this.logger.warn(
+            `AI chat stream DIAGNOSTIC (abort/disconnect): elapsed=${diagNow - streamStartedAt}ms ` +
+              `firstChunkLatency=${firstModelChunkAt ? firstModelChunkAt - streamStartedAt : 'none'}ms ` +
+              `silentGapBeforeDrop=${diagNow - lastModelChunkAt}ms heartbeatsSent=${heartbeatsSent} ` +
+              `steps=${steps.length}`,
+          );
+          await finalizeAssistant(
+            flushAssistant(capturedSteps, inProgressText, 'aborted'),
+          );
+          await closeExternalClients();
+        },
       });
 
       // Drain the stream independently of the client socket so the turn always
@@ -652,7 +808,10 @@ export class AiChatService {
         'punctuation at the end.',
       prompt: firstMessage.slice(0, 2000),
     });
-    const title = text.trim().replace(/^["']|["']$/g, '').slice(0, 120);
+    const title = text
+      .trim()
+      .replace(/^["']|["']$/g, '')
+      .slice(0, 120);
     if (title) {
       await this.aiChatRepo.update(chatId, { title }, workspaceId);
     }
@@ -975,38 +1134,132 @@ export function rowToUiMessage(row: AiChatMessage): Omit<UIMessage, 'id'> & {
 }
 
 /**
- * Build the assistant-message record persisted on a partial/failed turn (the
- * streamText onError / onAbort paths). Captures the partial answer the user
- * already saw: each finished step's text + tool parts (via assistantParts),
- * then the in-progress step's text appended last. When `errorText` is provided
- * it is recorded in metadata.error so the cause shows in history; an aborted
- * turn passes none. Pure, so the partial-recording shape is unit-testable
- * without seaming streamText.
+ * The persisted-row patch shape produced by {@link flushAssistant}. It is the
+ * SAME shape the assistant repo insert/update consume (content + toolCalls +
+ * metadata) plus the lifecycle `status` column added in #183.
  */
-export function buildPartialAssistantRecord(
-  steps: ReadonlyArray<StepLike> | undefined,
+export interface AssistantFlush {
+  content: string;
+  toolCalls: unknown;
+  metadata: Record<string, unknown>;
+  status: 'streaming' | 'completed' | 'error' | 'aborted';
+}
+
+/**
+ * Pure decision for the terminal finalize (#183): given whether the upfront
+ * assistant row exists (`assistantId`), choose whether the terminal payload is
+ * written by UPDATEing that row or — when the upfront insert failed and there is
+ * no id — by INSERTing a fresh terminal row so the turn is not lost entirely.
+ * Returns `{ kind: 'update', id }` or `{ kind: 'insert' }`. Extracted so the
+ * fallback-insert branch (the only safety against losing a turn whose upfront
+ * insert failed) is unit-testable without seaming streamText.
+ */
+export function planFinalizeAssistant(
+  assistantId: string | undefined,
+): { kind: 'update'; id: string } | { kind: 'insert' } {
+  return assistantId ? { kind: 'update', id: assistantId } : { kind: 'insert' };
+}
+
+/** The repo surface the terminal finalize needs (structural — the real repo and
+ *  a test mock both satisfy it). */
+export interface FinalizeRepo {
+  insert(insertable: Record<string, unknown>): Promise<unknown>;
+  update(
+    id: string,
+    workspaceId: string,
+    patch: AssistantFlush,
+  ): Promise<unknown>;
+}
+
+/**
+ * Apply a finalize `plan` to the repo with the terminal `flushed` payload (#183):
+ * UPDATE the upfront row, or INSERT a fresh terminal row as the fallback when the
+ * upfront insert failed. The SINGLE dispatch shared by the service's
+ * finalizeAssistant and its test, so the test exercises the real path instead of
+ * a copy (#186 review). Pure of error handling — the caller wraps it.
+ */
+export async function applyFinalize(
+  repo: FinalizeRepo,
+  plan: { kind: 'update'; id: string } | { kind: 'insert' },
+  base: { chatId: string; workspaceId: string; userId: string },
+  flushed: AssistantFlush,
+): Promise<void> {
+  if (plan.kind === 'update') {
+    await repo.update(plan.id, base.workspaceId, flushed);
+    return;
+  }
+  await repo.insert({
+    chatId: base.chatId,
+    workspaceId: base.workspaceId,
+    userId: base.userId,
+    role: 'assistant',
+    content: flushed.content,
+    toolCalls: flushed.toolCalls ?? null,
+    metadata: flushed.metadata,
+    status: flushed.status,
+  });
+}
+
+/**
+ * PURE assistant-row builder (#183 step-granular durability). Given the turn's
+ * accumulated steps + the in-progress (not-yet-finished) text + the lifecycle
+ * status, it returns the row patch to persist. The SAME path runs for the
+ * upfront insert (empty steps, status 'streaming'), every per-step update, and
+ * the terminal finalize (completed/error/aborted) — and a future background
+ * worker can call it identically, so it must stay a pure function of its inputs
+ * (NO `this`, no IO).
+ *
+ * `metadata.parts` is built by assistantParts over the finished steps, then the
+ * in-progress text appended as a trailing text part, so rowToUiMessage /
+ * findRecent keep replaying the turn unchanged. `metadata.finishReason`,
+ * `metadata.error`, `metadata.usage` and `metadata.contextTokens` are attached
+ * only when provided/relevant, matching the pre-#183 onFinish/onError records.
+ */
+export function flushAssistant(
+  capturedSteps: ReadonlyArray<StepLike> | undefined,
   inProgressText: string,
-  finishReason: 'error' | 'aborted',
-  errorText?: string,
-): { text: string; toolCalls: unknown; metadata: Record<string, unknown> } {
-  const finished = steps ?? [];
+  status: 'streaming' | 'completed' | 'error' | 'aborted',
+  extra?: {
+    finishReason?: string;
+    usage?: ChatStreamUsage | StreamUsage | undefined;
+    contextTokens?: number;
+    error?: string;
+  },
+): AssistantFlush {
+  const finished = capturedSteps ?? [];
   const stepsText = finished.map((s) => s.text ?? '').join('');
   const trailing = inProgressText ?? '';
   // assistantParts emits text parts only for FINISHED steps; append the
-  // in-progress step's text (the answer cut off by the error) as the last text
-  // part so the persisted parts match what streamed to the client.
+  // in-progress step's text (the partial answer cut off by an error/abort, or
+  // simply not yet flushed mid-stream) as the last text part so the persisted
+  // parts match what streamed to the client.
   const parts = assistantParts(finished, '') as unknown as Array<
     Record<string, unknown>
   >;
   if (trailing) parts.push({ type: 'text', text: trailing });
+
+  const metadata: Record<string, unknown> = {
+    parts: parts as unknown as UIMessage['parts'],
+  };
+  // finishReason: prefer an explicit one; else derive a sensible value from the
+  // terminal status (so onError/onAbort records keep their historical reason).
+  if (extra?.finishReason) {
+    metadata.finishReason = extra.finishReason;
+  } else if (status === 'error' || status === 'aborted') {
+    metadata.finishReason = status;
+  }
+  if (extra?.usage !== undefined) {
+    metadata.usage =
+      normalizeStreamUsage(extra.usage as StreamUsage) ?? extra.usage;
+  }
+  if (extra?.contextTokens) metadata.contextTokens = extra.contextTokens;
+  if (extra?.error) metadata.error = extra.error;
+
   return {
-    text: stepsText + trailing,
+    content: stepsText + trailing,
     toolCalls: serializeSteps(finished),
-    metadata: {
-      finishReason,
-      parts: parts as unknown as UIMessage['parts'],
-      ...(errorText ? { error: errorText } : {}),
-    },
+    metadata,
+    status,
   };
 }
 

apps/server/src/core/ai-chat/chat-markdown.util.spec.ts

@@ -0,0 +1,295 @@
+import { buildChatMarkdown, normalizeLang } from './chat-markdown.util';
+import type { AiChatMessage } from '@docmost/db/types/entity.types';
+
+/**
+ * normalizeLang: the client sends `i18n.language` — a FULL locale tag like
+ * 'en-US' / 'ru-RU', NOT a bare 'en'/'ru'. A `@IsIn(['en','ru'])` DTO rejected
+ * that with a 400 (caught in real-browser testing); the export now accepts any
+ * string and normalizes here. Guards that regression.
+ */
+describe('normalizeLang', () => {
+  it("maps any 'ru…' locale tag to ru", () => {
+    expect(normalizeLang('ru')).toBe('ru');
+    expect(normalizeLang('ru-RU')).toBe('ru');
+    expect(normalizeLang('RU-ru')).toBe('ru');
+  });
+
+  it('maps everything else (incl. region-qualified English) to en', () => {
+    expect(normalizeLang('en')).toBe('en');
+    expect(normalizeLang('en-US')).toBe('en');
+    expect(normalizeLang('fr-FR')).toBe('en');
+    expect(normalizeLang(undefined)).toBe('en');
+    expect(normalizeLang('')).toBe('en');
+  });
+});
+
+/**
+ * Unit tests for the SERVER Markdown export (#183). Mirrors the coverage of the
+ * (now-removed) client chat-markdown tests: heading/metadata, role labels, text
+ * + tool blocks, token footers, the interrupted-turn note, and NULL-status
+ * (legacy) rows. The export embeds a live `new Date().toISOString()` timestamp;
+ * we never assert it, only the deterministic structure.
+ */
+
+function row(partial: Partial<AiChatMessage>): AiChatMessage {
+  return {
+    id: partial.id ?? 'id',
+    chatId: partial.chatId ?? 'chat-1',
+    workspaceId: partial.workspaceId ?? 'ws-1',
+    userId: partial.userId ?? null,
+    role: partial.role ?? 'user',
+    content: partial.content ?? null,
+    toolCalls: partial.toolCalls ?? null,
+    metadata: partial.metadata ?? null,
+    status: partial.status ?? null,
+    createdAt: partial.createdAt ?? ('2026-06-21T00:00:00.000Z' as never),
+    updatedAt: partial.updatedAt ?? ('2026-06-21T00:00:00.000Z' as never),
+    deletedAt: partial.deletedAt ?? null,
+  } as AiChatMessage;
+}
+
+describe('buildChatMarkdown (server) — structure', () => {
+  it('emits the title heading, chat id and message count', () => {
+    const md = buildChatMarkdown({
+      title: 'My chat',
+      chatId: 'chat-123',
+      rows: [],
+    });
+    expect(md).toContain('# My chat');
+    expect(md).toContain('- Chat ID: `chat-123`');
+    expect(md).toContain('- Messages: 0');
+  });
+
+  it('falls back to "Untitled chat" with no title (en)', () => {
+    const md = buildChatMarkdown({ title: null, chatId: 'c', rows: [] });
+    expect(md).toContain('# Untitled chat');
+  });
+
+  it('localizes fixed labels with lang=ru (structure stays English)', () => {
+    const md = buildChatMarkdown({
+      title: null,
+      chatId: 'c',
+      lang: 'ru',
+      rows: [row({ role: 'assistant', content: 'hi' })],
+    });
+    expect(md).toContain('# Без названия');
+    expect(md).toContain('## 1. ИИ-агент');
+    // Structural words remain English.
+    expect(md).toContain('- Chat ID:');
+  });
+
+  it('numbers messages and labels roles (You / AI agent)', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({ role: 'user', content: 'question' }),
+        row({ role: 'assistant', content: 'answer' }),
+      ],
+    });
+    expect(md).toContain('## 1. You');
+    expect(md).toContain('question');
+    expect(md).toContain('## 2. AI agent');
+    expect(md).toContain('answer');
+  });
+
+  it('renders a tool part with fenced input/output and the friendly label', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({
+          role: 'assistant',
+          content: 'done',
+          metadata: {
+            parts: [
+              {
+                type: 'tool-getPage',
+                state: 'output-available',
+                input: { id: 'p1' },
+                output: { title: 'Hello' },
+              },
+              { type: 'text', text: 'done' },
+            ],
+          } as never,
+        }),
+      ],
+    });
+    expect(md).toContain('**Tool: Read page** (`getPage`) — done');
+    expect(md).toContain('Input:');
+    expect(md).toContain('"id": "p1"');
+    expect(md).toContain('Output:');
+    expect(md).toContain('"title": "Hello"');
+  });
+
+  // #186 re-review pt 1: restore the parity coverage of the removed client spec —
+  // error state, unknown-tool fallback (en + ru), and the circular-stringify catch.
+  it('renders a tool part in the error state with its errorText', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({
+          role: 'assistant',
+          metadata: {
+            parts: [
+              {
+                type: 'tool-getPage',
+                state: 'output-error',
+                input: { id: 'p1' },
+                errorText: 'page not found',
+              },
+            ],
+          } as never,
+        }),
+      ],
+    });
+    expect(md).toContain('**Tool: Read page** (`getPage`) — error');
+    expect(md).toContain('**Error:** page not found');
+  });
+
+  it('falls back to "Ran tool <name>" for an unknown tool (en) and the ru variant', () => {
+    const parts = [
+      {
+        type: 'tool-mysteryTool',
+        state: 'output-available',
+        output: { ok: 1 },
+      },
+    ];
+    const en = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [row({ role: 'assistant', metadata: { parts } as never })],
+    });
+    expect(en).toContain('**Tool: Ran tool mysteryTool** (`mysteryTool`)');
+    const ru = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      lang: 'ru',
+      rows: [row({ role: 'assistant', metadata: { parts } as never })],
+    });
+    expect(ru).toContain('Выполнил инструмент mysteryTool');
+  });
+
+  it('does not throw on a circular tool output (falls back to String)', () => {
+    const circular: Record<string, unknown> = {};
+    circular.self = circular;
+    expect(() =>
+      buildChatMarkdown({
+        title: 'T',
+        chatId: 'c',
+        rows: [
+          row({
+            role: 'assistant',
+            metadata: {
+              parts: [
+                {
+                  type: 'tool-getPage',
+                  state: 'output-available',
+                  output: circular,
+                },
+              ],
+            } as never,
+          }),
+        ],
+      }),
+    ).not.toThrow();
+  });
+
+  it('emits a token footer + total when usage is present', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({
+          role: 'assistant',
+          content: 'a',
+          metadata: {
+            usage: {
+              inputTokens: 100,
+              outputTokens: 20,
+              totalTokens: 120,
+              reasoningTokens: 8,
+            },
+          } as never,
+        }),
+      ],
+    });
+    expect(md).toContain('- Total tokens: 120');
+    expect(md).toContain(
+      '_Tokens — in: 100, out: 20, reasoning: 8, total: 120_',
+    );
+  });
+
+  it('flags a still-streaming (interrupted) row', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({ role: 'assistant', content: 'partial', status: 'streaming' }),
+      ],
+    });
+    expect(md).toContain('still being generated');
+  });
+
+  it('does NOT flag a completed row', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [row({ role: 'assistant', content: 'final', status: 'completed' })],
+    });
+    expect(md).not.toContain('still being generated');
+  });
+
+  it('renders a legacy NULL-status row (no parts) from plain content', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({ role: 'assistant', content: 'legacy answer', status: null }),
+      ],
+    });
+    expect(md).toContain('legacy answer');
+    expect(md).not.toContain('still being generated');
+  });
+
+  it('renders a persisted error', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({
+          role: 'assistant',
+          content: '',
+          status: 'error',
+          metadata: { error: '401: Unauthorized' } as never,
+        }),
+      ],
+    });
+    expect(md).toContain('**⚠️ Error:** 401: Unauthorized');
+  });
+
+  it('escapes embedded triple-backtick fences with a longer delimiter', () => {
+    const md = buildChatMarkdown({
+      title: 'T',
+      chatId: 'c',
+      rows: [
+        row({
+          role: 'assistant',
+          content: 'x',
+          metadata: {
+            parts: [
+              {
+                type: 'tool-getPage',
+                state: 'output-available',
+                output: '```inner```',
+              },
+            ],
+          } as never,
+        }),
+      ],
+    });
+    // A 4-backtick fence wraps content that itself contains a 3-backtick run.
+    expect(md).toContain('````');
+  });
+});

apps/server/src/core/ai-chat/chat-markdown.util.ts

@@ -0,0 +1,299 @@
+/**
+ * Server-side Markdown export for an AI agent chat (#183). The DB is the single
+ * source of truth: this renders a chat purely from its persisted message rows
+ * (`AiChatMessage[]` — role / content / metadata.parts / toolCalls / usage).
+ * Because the assistant row is now persisted UPFRONT and updated per step, an
+ * interrupted turn is included up to its last finished step.
+ *
+ * Ported from the client `utils/chat-markdown.ts`. It is a PURE function (apart
+ * from `new Date()` for the export timestamp), so it is straightforward to
+ * unit-test and a future background worker can reuse it.
+ *
+ * Only a few fixed role/tool labels are localized via the `lang` param; the
+ * structural document words (Input/Output/Error/Tokens/...) stay English because
+ * the output is a technical artifact.
+ */
+
+import type { AiChatMessage } from '@docmost/db/types/entity.types';
+
+/** Supported export label languages. Defaults to English. */
+export type ExportLang = 'en' | 'ru';
+
+/**
+ * Normalize an arbitrary client locale code to a supported export language. The
+ * client sends `i18n.language`, which is a FULL locale tag (e.g. `en-US`,
+ * `ru-RU`), not a bare `en`/`ru` — so match on the language subtag and fall back
+ * to English for anything non-Russian.
+ */
+export function normalizeLang(lang?: string): ExportLang {
+  return lang?.toLowerCase().startsWith('ru') ? 'ru' : 'en';
+}
+
+/** A single AI SDK UIMessage part (text part or a tool part). */
+interface ExportPart {
+  type: string;
+  text?: string;
+  state?: string;
+  toolName?: string;
+  input?: unknown;
+  output?: unknown;
+  errorText?: string;
+}
+
+/** Authoritative per-turn usage the server attaches to a message row. */
+interface UsageLike {
+  inputTokens?: number;
+  outputTokens?: number;
+  totalTokens?: number;
+  reasoningTokens?: number;
+}
+
+/** Localized label table. The client-side Markdown builder was removed by #183
+ *  (the export is now server-side only), so this no longer mirrors a second
+ *  exporter — instead the tool-action labels are kept in parity with the
+ *  on-screen action-log labels in the client's `tool-parts.tsx` (`toolLabelKey`)
+ *  so the export reads the same as the UI. Only role + tool-action labels are
+ *  localized; everything structural is an English constant in the renderer. */
+const LABELS: Record<
+  ExportLang,
+  {
+    untitled: string;
+    aiAgent: string;
+    you: string;
+    tools: Record<string, string>;
+    ranTool: (name: string) => string;
+    stillGenerating: string;
+  }
+> = {
+  en: {
+    untitled: 'Untitled chat',
+    aiAgent: 'AI agent',
+    you: 'You',
+    tools: {
+      searchPages: 'Searched pages',
+      getPage: 'Read page',
+      createPage: 'Created page',
+      updatePageContent: 'Updated page',
+      renamePage: 'Renamed page',
+      movePage: 'Moved page',
+      deletePage: 'Deleted page (to trash)',
+      createComment: 'Commented',
+      resolveComment: 'Resolved comment',
+    },
+    ranTool: (name) => `Ran tool ${name}`,
+    stillGenerating:
+      'This message is still being generated — the export captured a partial, in-progress response.',
+  },
+  ru: {
+    untitled: 'Без названия',
+    aiAgent: 'ИИ-агент',
+    you: 'Вы',
+    tools: {
+      searchPages: 'Искал по страницам',
+      getPage: 'Прочитал страницу',
+      createPage: 'Создал страницу',
+      updatePageContent: 'Обновил страницу',
+      renamePage: 'Переименовал страницу',
+      movePage: 'Переместил страницу',
+      deletePage: 'Удалил страницу (в корзину)',
+      createComment: 'Прокомментировал',
+      resolveComment: 'Закрыл комментарий',
+    },
+    ranTool: (name) => `Выполнил инструмент ${name}`,
+    stillGenerating:
+      'Это сообщение всё ещё генерируется — экспорт захватил частичный, незавершённый ответ.',
+  },
+};
+
+/** True for AI SDK tool parts (static `tool-*` or `dynamic-tool`). */
+function isToolPart(type: string): boolean {
+  return type.startsWith('tool-') || type === 'dynamic-tool';
+}
+
+/** Extract the tool name from a part `type` of `tool-${name}` (or dynamic). */
+function getToolName(part: ExportPart): string {
+  if (part.type === 'dynamic-tool') return part.toolName ?? '';
+  return part.type.startsWith('tool-')
+    ? part.type.slice('tool-'.length)
+    : part.type;
+}
+
+/** Map an AI SDK tool-part state to the 3 states the action-log renders. */
+function toolRunState(state: string | undefined): 'running' | 'done' | 'error' {
+  if (state === 'output-error' || state === 'output-denied') return 'error';
+  if (state === 'output-available') return 'done';
+  return 'running';
+}
+
+/** Resolve a tool's friendly action-log label (localized) from its name. */
+function toolLabel(name: string, lang: ExportLang): string {
+  return LABELS[lang].tools[name] ?? LABELS[lang].ranTool(name);
+}
+
+/**
+ * Stringify an arbitrary tool input/output value for a fenced block. Strings
+ * pass through as-is; everything else is pretty-printed JSON, falling back to
+ * `String(value)` if serialization throws (e.g. a circular structure).
+ */
+function stringify(value: unknown): string {
+  if (typeof value === 'string') return value;
+  try {
+    return JSON.stringify(value, null, 2);
+  } catch {
+    return String(value);
+  }
+}
+
+/**
+ * Wrap `code` in a fenced code block whose backtick delimiter is LONGER than the
+ * longest backtick run inside the content, so embedded backticks (or a literal
+ * ``` fence) never break out of the block. Minimum 3 backticks.
+ */
+function fence(code: string, lang = ''): string {
+  const runs: string[] = code.match(/`+/g) ?? [];
+  const longest = runs.reduce((m, s) => Math.max(m, s.length), 0);
+  const delim = '`'.repeat(Math.max(3, longest + 1));
+  return `${delim}${lang}\n${code}\n${delim}`;
+}
+
+/** Per-row token count, mirroring the header sum in the client window. */
+function rowTokens(usage: UsageLike): number {
+  return (
+    usage.totalTokens ?? (usage.inputTokens ?? 0) + (usage.outputTokens ?? 0)
+  );
+}
+
+/** Render one message's UIMessage parts into an array of Markdown blocks
+ *  (text blocks + tool blocks). Mirrors the client renderer / MessageItem. */
+function renderMessageParts(parts: ExportPart[], lang: ExportLang): string[] {
+  const out: string[] = [];
+
+  for (const part of parts) {
+    if (part.type === 'text') {
+      const text = (part.text ?? '').trim();
+      if (text.length > 0) out.push(text);
+      continue;
+    }
+
+    if (!isToolPart(part.type)) continue;
+
+    const name = getToolName(part);
+    const label = toolLabel(name, lang);
+    const state = toolRunState(part.state);
+
+    const toolLines: string[] = [`**Tool: ${label}** (\`${name}\`) — ${state}`];
+    if (part.input !== undefined) {
+      toolLines.push('Input:');
+      toolLines.push(fence(stringify(part.input), 'json'));
+    }
+    if (part.output !== undefined) {
+      toolLines.push('Output:');
+      toolLines.push(fence(stringify(part.output), 'json'));
+    }
+    if (part.errorText) {
+      toolLines.push(`**Error:** ${part.errorText}`);
+    }
+    out.push(toolLines.join('\n\n'));
+  }
+
+  return out;
+}
+
+/** Resolve a persisted row's parts: prefer the rich persisted parts, else a
+ *  single text part built from the plain-text content (mirrors rowToUiMessage). */
+function rowParts(row: AiChatMessage): ExportPart[] {
+  const meta = (row.metadata ?? {}) as { parts?: ExportPart[] };
+  return Array.isArray(meta.parts) && meta.parts.length > 0
+    ? meta.parts
+    : [{ type: 'text', text: row.content ?? '' }];
+}
+
+/**
+ * Serialize a chat to a Markdown string from its persisted rows. Source = DB
+ * ONLY (no live client state). A row whose `status` is still 'streaming' is an
+ * interrupted turn that the export captured mid-flight; it is rendered up to its
+ * last finished step and flagged "still generating".
+ */
+export function buildChatMarkdown(args: {
+  title: string | null;
+  chatId: string;
+  rows: AiChatMessage[];
+  // Accepts a full client locale tag (e.g. 'en-US'/'ru-RU'); normalized below.
+  lang?: string;
+}): string {
+  const { title, chatId, rows } = args;
+  const lang: ExportLang = normalizeLang(args.lang);
+  const L = LABELS[lang];
+  const blocks: string[] = [];
+
+  const heading = (title ?? '').trim() || L.untitled;
+  blocks.push(`# ${heading}`);
+
+  const usageOf = (row: AiChatMessage): UsageLike | undefined => {
+    const meta = (row.metadata ?? {}) as { usage?: UsageLike };
+    return meta.usage;
+  };
+  const errorOf = (row: AiChatMessage): string | undefined => {
+    const meta = (row.metadata ?? {}) as { error?: string };
+    return meta.error;
+  };
+
+  // Metadata bullet list. Total tokens is only shown when there is a sum.
+  const totalTokens = rows.reduce((sum, row) => {
+    const usage = usageOf(row);
+    return usage ? sum + rowTokens(usage) : sum;
+  }, 0);
+  const meta = [
+    `- Chat ID: \`${chatId}\``,
+    `- Exported: ${new Date().toISOString()}`,
+    `- Messages: ${rows.length}`,
+  ];
+  if (totalTokens > 0) meta.push(`- Total tokens: ${totalTokens}`);
+  blocks.push(meta.join('\n'));
+
+  rows.forEach((row, index) => {
+    blocks.push('---');
+
+    const roleLabel = row.role === 'assistant' ? L.aiAgent : L.you;
+    blocks.push(`## ${index + 1}. ${roleLabel}`);
+
+    // Created-at kept in source as an HTML comment (out of the rendered prose).
+    if (row.createdAt) {
+      const iso =
+        row.createdAt instanceof Date
+          ? row.createdAt.toISOString()
+          : String(row.createdAt);
+      blocks.push(`<!-- ${iso} -->`);
+    }
+
+    blocks.push(...renderMessageParts(rowParts(row), lang));
+
+    // A still-'streaming' row is an interrupted/in-progress turn captured by the
+    // export; record that so the partial answer is not mistaken for complete.
+    if (row.status === 'streaming') {
+      blocks.push(`_⏳ ${L.stillGenerating}_`);
+    }
+
+    const error = errorOf(row);
+    if (error) {
+      blocks.push(`**⚠️ Error:** ${error}`);
+    }
+
+    const usage = usageOf(row);
+    if (usage) {
+      const total = usage.totalTokens ?? rowTokens(usage);
+      const reasoning =
+        usage.reasoningTokens && usage.reasoningTokens > 0
+          ? `, reasoning: ${usage.reasoningTokens}`
+          : '';
+      blocks.push(
+        `_Tokens — in: ${usage.inputTokens ?? '?'}, out: ${
+          usage.outputTokens ?? '?'
+        }${reasoning}, total: ${total}_`,
+      );
+    }
+  });
+
+  // Blank line between blocks so the Markdown renders cleanly.
+  return blocks.join('\n\n');
+}

apps/server/src/core/ai-chat/dto/ai-chat.dto.ts

@@ -26,3 +26,17 @@ export class GetChatMessagesDto {
   @IsString()
   cursor?: string;
 }
+
+/** Export a chat to Markdown (#183). `lang` localizes the few fixed
+ *  role/tool-action labels; defaults to English server-side. */
+export class ExportChatDto {
+  @IsString()
+  chatId: string;
+
+  // A full client locale tag (e.g. 'en-US', 'ru-RU') — normalized server-side to
+  // a supported export language (see normalizeLang). Accept any string so a
+  // region-qualified locale is not rejected (the 400 that broke the real client).
+  @IsOptional()
+  @IsString()
+  lang?: string;
+}

apps/server/src/core/ai-chat/external-mcp/dto/create-mcp-server.dto.ts

@@ -42,6 +42,15 @@ export class CreateMcpServerDto {
   @IsString({ each: true })
   toolAllowlist?: string[];
 
+  // Admin-authored guidance ("how/when to use this server's tools") injected
+  // into the agent system prompt next to the tool descriptions (#180). Trusted,
+  // NON-secret (so it IS returned). Capped to bound prompt/token size (the
+  // built-in guide is ~1.5KB). Blank => stored as null.
+  @IsOptional()
+  @IsString()
+  @MaxLength(4000)
+  instructions?: string;
+
   @IsOptional()
   @IsBoolean()
   enabled?: boolean;

apps/server/src/core/ai-chat/external-mcp/dto/mcp-server-instructions.dto.spec.ts

@@ -0,0 +1,75 @@
+import 'reflect-metadata';
+import { plainToInstance } from 'class-transformer';
+import { validateSync } from 'class-validator';
+import { CreateMcpServerDto } from './create-mcp-server.dto';
+import { UpdateMcpServerDto } from './update-mcp-server.dto';
+
+/**
+ * API-boundary validation for the per-server `instructions` field (#180): a free
+ * text guide injected into the agent system prompt. It is optional, must be a
+ * string, and is bounded by @MaxLength(4000) to cap prompt/token size.
+ */
+describe('MCP server DTO instructions validation', () => {
+  function validateCreate(payload: unknown) {
+    const dto = plainToInstance(CreateMcpServerDto, payload);
+    return validateSync(dto as object);
+  }
+  function validateUpdate(payload: unknown) {
+    const dto = plainToInstance(UpdateMcpServerDto, payload);
+    return validateSync(dto as object);
+  }
+
+  const base = {
+    name: 'Tavily',
+    transport: 'http',
+    url: 'https://example.com/mcp',
+  };
+
+  it('accepts an omitted instructions field on create', () => {
+    expect(validateCreate({ ...base })).toHaveLength(0);
+  });
+
+  it('accepts a reasonable instructions string on create', () => {
+    expect(
+      validateCreate({ ...base, instructions: 'Use search for fresh facts.' }),
+    ).toHaveLength(0);
+  });
+
+  it('rejects instructions over MaxLength(4000) on create', () => {
+    const errors = validateCreate({
+      ...base,
+      instructions: 'a'.repeat(4001),
+    });
+    expect(
+      errors.some(
+        (e) =>
+          e.property === 'instructions' &&
+          e.constraints !== undefined &&
+          'maxLength' in e.constraints,
+      ),
+    ).toBe(true);
+  });
+
+  it('accepts instructions of exactly 4000 chars on create', () => {
+    expect(
+      validateCreate({ ...base, instructions: 'a'.repeat(4000) }),
+    ).toHaveLength(0);
+  });
+
+  it('rejects a non-string instructions value', () => {
+    const errors = validateCreate({ ...base, instructions: 123 });
+    expect(errors.some((e) => e.property === 'instructions')).toBe(true);
+  });
+
+  it('rejects instructions over MaxLength(4000) on update', () => {
+    const errors = validateUpdate({ instructions: 'a'.repeat(4001) });
+    expect(
+      errors.some(
+        (e) =>
+          e.property === 'instructions' &&
+          e.constraints !== undefined &&
+          'maxLength' in e.constraints,
+      ),
+    ).toBe(true);
+  });
+});

apps/server/src/core/ai-chat/external-mcp/dto/update-mcp-server.dto.ts

@@ -43,6 +43,13 @@ export class UpdateMcpServerDto {
   @IsString({ each: true })
   toolAllowlist?: string[];
 
+  // Admin-authored prompt guidance (#180). Absent => unchanged; blank => cleared
+  // (stored as null by the repo). Capped to bound prompt/token size.
+  @IsOptional()
+  @IsString()
+  @MaxLength(4000)
+  instructions?: string;
+
   @IsOptional()
   @IsBoolean()
   enabled?: boolean;

apps/server/src/core/ai-chat/external-mcp/mcp-clients.service.ts

@@ -33,6 +33,26 @@ interface ServerOutcome {
   reason?: string;
 }
 
+/**
+ * One server's admin-authored guidance for the agent system prompt (#180).
+ * Built ONLY for a server that actually connected AND contributed ≥1 tool
+ * (after the allowlist filter) AND has non-blank guidance — so a guide never
+ * appears for a server whose tools the agent cannot actually call.
+ */
+export interface McpServerInstruction {
+  /** Display name of the server (for the prompt section header). */
+  serverName: string;
+  /**
+   * The tool-name namespace prefix the server's tools were merged under
+   * (sanitized name, e.g. `tavily`). The prompt renders this as `tavily_*` so
+   * the model can connect the guidance to the actual tool names. Advisory:
+   * individual tools may carry a disambiguating suffix on rare collisions.
+   */
+  toolPrefix: string;
+  /** The trusted, non-blank guidance text. */
+  instructions: string;
+}
+
 export interface ExternalToolset {
   /** Namespaced external tools, merge-ready into the agent toolset. */
   tools: Record<string, Tool>;
@@ -40,6 +60,11 @@ export interface ExternalToolset {
   clients: Closable[];
   /** Per-server connect outcomes so the UI can show unavailable servers. */
   outcomes: ServerOutcome[];
+  /**
+   * Per-server prompt guidance for connected servers that contributed ≥1 tool
+   * and have non-blank instructions. Empty when no server qualifies.
+   */
+  instructions: McpServerInstruction[];
 }
 
 /** Connect+tools() timeout per server — a slow server must not stall the turn. */
@@ -60,6 +85,8 @@ interface CacheEntry {
   tools: Record<string, Tool>;
   clients: McpClient[];
   outcomes: ServerOutcome[];
+  /** Prompt guidance for qualifying servers (see McpServerInstruction). */
+  instructions: McpServerInstruction[];
   expiresAt: number;
   /** Active leases (turns currently using these clients). */
   refCount: number;
@@ -141,6 +168,7 @@ export class McpClientsService {
       tools: entry.tools,
       clients: [release],
       outcomes: entry.outcomes,
+      instructions: entry.instructions,
     };
   }
 
@@ -225,6 +253,7 @@ export class McpClientsService {
     const outcomes: ServerOutcome[] = [];
     // Per-call total wall-clock cap, read once for this build (env-overridable).
     const callTimeoutMs = mcpCallTimeoutMs();
+    const instructions: McpServerInstruction[] = [];
 
     for (const server of servers) {
       try {
@@ -233,17 +262,33 @@ export class McpClientsService {
         clients.push(client);
         const allow = server.toolAllowlist;
         const picked =
-          Array.isArray(allow) && allow.length > 0
-            ? pick(raw, allow)
-            : raw;
+          Array.isArray(allow) && allow.length > 0 ? pick(raw, allow) : raw;
         // Bound each tool's execute with a per-call total-timeout guard before
         // merging, so a single chatty-but-stuck call is aborted after the cap.
         const guarded = wrapToolsWithCallTimeout(picked, callTimeoutMs);
         // Namespace each tool with the sanitized server name AND disambiguate
         // against names already merged from earlier servers, so no external
-        // tool is silently overwritten on collision.
-        this.mergeNamespaced(tools, guarded, server.name, server.id);
+        // tool is silently overwritten on collision. The returned count drives
+        // whether this server's prompt guidance is included (≥1 tool merged).
+        const merged = this.mergeNamespaced(
+          tools,
+          guarded,
+          server.name,
+          server.id,
+        );
         outcomes.push({ name: server.name, ok: true });
+        // Include this server's guidance ONLY when it actually contributed at
+        // least one tool the agent can call (allowlist may have filtered all of
+        // them out) AND the admin authored non-blank instructions. The header
+        // prefix is the sanitized server name (= the tool namespace prefix).
+        const guide = server.instructions?.trim();
+        if (merged.count > 0 && guide) {
+          instructions.push({
+            serverName: server.name,
+            toolPrefix: merged.prefix,
+            instructions: guide,
+          });
+        }
       } catch (err) {
         // A failed server is skipped — the turn proceeds with the rest. Log a
         // short warning (never the URL/headers) so ops can see degradation, and
@@ -260,6 +305,7 @@ export class McpClientsService {
       tools,
       clients,
       outcomes,
+      instructions,
       expiresAt: Date.now() + CACHE_TTL_MS,
       refCount: 0,
       evicted: false,
@@ -276,16 +322,19 @@ export class McpClientsService {
    * renaming any key that would collide with an already-merged tool (different
    * servers with the same sanitized name, or duplicates after truncation), so
    * no external tool is silently dropped via overwrite.
+   *
+   * Returns how many tools this server actually contributed and the namespace
+   * prefix used (the sanitized server name) so the caller can attach the
+   * server's prompt guidance only when ≥1 tool was merged.
    */
   private mergeNamespaced(
     target: Record<string, Tool>,
     picked: Record<string, Tool>,
     serverName: string,
     serverId: string,
-  ): void {
-    for (const [name, tool] of Object.entries(
-      namespace(picked, serverName),
-    )) {
+  ): { count: number; prefix: string } {
+    let count = 0;
+    for (const [name, tool] of Object.entries(namespace(picked, serverName))) {
       let key = name;
       if (key in target) {
         const original = key;
@@ -295,7 +344,9 @@ export class McpClientsService {
         );
       }
       target[key] = tool;
+      count += 1;
     }
+    return { count, prefix: namespacePrefix(serverName) };
   }
 
   /**
@@ -371,9 +422,7 @@ export class McpClientsService {
 
   /** Close clients, swallowing close errors so they never break a response. */
   private async closeClients(clients: McpClient[]): Promise<void> {
-    await Promise.all(
-      clients.map((c) => c.close().catch(() => undefined)),
-    );
+    await Promise.all(clients.map((c) => c.close().catch(() => undefined)));
   }
 }
 
@@ -386,9 +435,10 @@ export class McpClientsService {
  * lookup hands net/tls.connect ONLY a set that passed this check, so the kernel
  * can never connect to an address that did not pass the guard. Pure — no I/O.
  */
-export function validateResolvedAddresses(
-  addrs: readonly LookupAddress[],
-): { ok: boolean; blockedHost?: string } {
+export function validateResolvedAddresses(addrs: readonly LookupAddress[]): {
+  ok: boolean;
+  blockedHost?: string;
+} {
   if (addrs.length === 0) {
     return { ok: false };
   }
@@ -524,7 +574,7 @@ function namespace(
   tools: Record<string, Tool>,
   serverName: string,
 ): Record<string, Tool> {
-  const prefix = sanitizeName(serverName) || 'mcp';
+  const prefix = namespacePrefix(serverName);
   const out: Record<string, Tool> = {};
   for (const [name, t] of Object.entries(tools)) {
     const safe = sanitizeName(name);
@@ -539,6 +589,15 @@ function namespace(
   return out;
 }
 
+/**
+ * The tool-name namespace prefix for a server: its sanitized name, or `mcp`
+ * when the name sanitizes to empty. Tools are merged as `${prefix}_${tool}`, so
+ * the prompt guidance refers to the server's tools as `${prefix}_*`.
+ */
+function namespacePrefix(serverName: string): string {
+  return sanitizeName(serverName) || 'mcp';
+}
+
 /** Reduce an arbitrary string to ^[a-zA-Z0-9_-]+, collapsing runs to '_'. */
 function sanitizeName(value: string): string {
   return value

apps/server/src/core/ai-chat/external-mcp/mcp-instructions.spec.ts

@@ -0,0 +1,168 @@
+import { type Tool } from 'ai';
+import { McpClientsService } from './mcp-clients.service';
+
+/**
+ * Tests for the per-server prompt guidance (#180) assembled by buildEntry and
+ * surfaced via toolsFor().instructions.
+ *
+ * REACHABILITY NOTE: buildEntry is a PRIVATE method; the smallest reachable
+ * public path is toolsFor() -> getOrBuildEntry -> buildEntry -> connect/tools()
+ * -> mergeNamespaced. We drive that path: stub the repo's `listEnabled` and spy
+ * on the private `connect` to return fake MCP clients whose `tools()` we control.
+ *
+ * Contract (all checked here): a server's guidance is included ONLY when the
+ * server actually connected AND contributed ≥1 callable tool (after the
+ * allowlist filter) AND its instructions are non-blank. The header carries the
+ * tool namespace prefix (the sanitized server name).
+ */
+function fakeTool(): Tool {
+  return { description: 'x', inputSchema: undefined } as unknown as Tool;
+}
+
+interface FakeServer {
+  id: string;
+  name: string;
+  transport: string;
+  url: string;
+  headersEnc: string | null;
+  toolAllowlist: string[] | null;
+  instructions: string | null;
+}
+
+function server(
+  over: Partial<FakeServer> & { id: string; name: string },
+): FakeServer {
+  return {
+    transport: 'http',
+    url: 'https://example.com/mcp',
+    headersEnc: null,
+    toolAllowlist: null,
+    instructions: null,
+    ...over,
+  };
+}
+
+async function instructionsFor(
+  servers: FakeServer[],
+  toolsByServerId: Record<string, Record<string, Tool>>,
+  // Server ids whose connect should THROW (simulating an unavailable server).
+  failingIds: Set<string> = new Set(),
+): Promise<
+  {
+    serverName: string;
+    toolPrefix: string;
+    instructions: string;
+  }[]
+> {
+  const repoStub = {
+    listEnabled: jest.fn().mockResolvedValue(servers),
+  };
+  const service = new McpClientsService(repoStub as never, {} as never);
+
+  jest
+    .spyOn(
+      service as unknown as { connect: (s: FakeServer) => unknown },
+      'connect',
+    )
+    .mockImplementation((s: FakeServer) => {
+      if (failingIds.has(s.id)) {
+        return Promise.reject(new Error('connection failed'));
+      }
+      return Promise.resolve({
+        tools: () => Promise.resolve(toolsByServerId[s.id] ?? {}),
+        close: () => Promise.resolve(),
+      });
+    });
+
+  const toolset = await service.toolsFor('ws-1');
+  await Promise.all(toolset.clients.map((c) => c.close()));
+  return toolset.instructions;
+}
+
+describe('external MCP per-server prompt guidance (via toolsFor)', () => {
+  afterEach(() => jest.restoreAllMocks());
+
+  it('includes guidance for a connected server with non-empty text and ≥1 tool', async () => {
+    const instructions = await instructionsFor(
+      [
+        server({
+          id: 'id-tavily',
+          name: 'Tavily',
+          instructions: 'Use tavily_search for fresh facts.',
+        }),
+      ],
+      { 'id-tavily': { search: fakeTool() } },
+    );
+
+    // sanitizeName preserves case (charset [a-zA-Z0-9_-]), so the prefix is the
+    // server name as-is for an already-clean name.
+    expect(instructions).toEqual([
+      {
+        serverName: 'Tavily',
+        toolPrefix: 'Tavily',
+        instructions: 'Use tavily_search for fresh facts.',
+      },
+    ]);
+  });
+
+  it('omits guidance when the server has no instructions', async () => {
+    const instructions = await instructionsFor(
+      [server({ id: 'id-1', name: 'Tavily', instructions: null })],
+      { 'id-1': { search: fakeTool() } },
+    );
+    expect(instructions).toEqual([]);
+  });
+
+  it('omits guidance when the instructions are only whitespace', async () => {
+    const instructions = await instructionsFor(
+      [server({ id: 'id-1', name: 'Tavily', instructions: '   ' })],
+      { 'id-1': { search: fakeTool() } },
+    );
+    expect(instructions).toEqual([]);
+  });
+
+  it('omits guidance for a server that contributed ZERO tools (allowlist filtered all out)', async () => {
+    const instructions = await instructionsFor(
+      [
+        server({
+          id: 'id-1',
+          name: 'Tavily',
+          instructions: 'guide',
+          // Allowlist names a tool the server does not expose -> 0 picked.
+          toolAllowlist: ['nonexistent'],
+        }),
+      ],
+      { 'id-1': { search: fakeTool() } },
+    );
+    expect(instructions).toEqual([]);
+  });
+
+  it('omits guidance for an unavailable (failed-connect) server', async () => {
+    const instructions = await instructionsFor(
+      [server({ id: 'id-1', name: 'Tavily', instructions: 'guide' })],
+      { 'id-1': { search: fakeTool() } },
+      new Set(['id-1']),
+    );
+    expect(instructions).toEqual([]);
+  });
+
+  it('includes only the qualifying servers among several', async () => {
+    const instructions = await instructionsFor(
+      [
+        server({ id: 'ok', name: 'Tavily', instructions: 'web guide' }),
+        server({ id: 'blank', name: 'Crawl', instructions: '' }),
+        server({ id: 'down', name: 'Down', instructions: 'never shown' }),
+      ],
+      {
+        ok: { search: fakeTool() },
+        blank: { crawl: fakeTool() },
+        down: { x: fakeTool() },
+      },
+      new Set(['down']),
+    );
+
+    expect(instructions).toEqual([
+      { serverName: 'Tavily', toolPrefix: 'Tavily', instructions: 'web guide' },
+    ]);
+  });
+});

apps/server/src/core/ai-chat/external-mcp/mcp-servers-to-view.spec.ts

@@ -17,6 +17,7 @@ function row(overrides: Partial<AiMcpServer>): AiMcpServer {
     enabled: true,
     toolAllowlist: null,
     headersEnc: null,
+    instructions: null,
     ...overrides,
   } as unknown as AiMcpServer;
 }
@@ -28,11 +29,7 @@ describe('McpServersService.toView (via list) — encrypted-header leak guard',
     };
     // secretBox + clients are unused by the list/toView path; pass stubs to
     // satisfy the constructor.
-    return new McpServersService(
-      repoStub as never,
-      {} as never,
-      {} as never,
-    );
+    return new McpServersService(repoStub as never, {} as never, {} as never);
   }
 
   it('exposes hasHeaders:true and NO headersEnc when auth headers are set', async () => {
@@ -67,6 +64,7 @@ describe('McpServersService.toView (via list) — encrypted-header leak guard',
         enabled: false,
         toolAllowlist: ['search'],
         headersEnc: 'BLOB',
+        instructions: 'Use search for fresh web facts.',
       }),
     ]);
 
@@ -80,6 +78,19 @@ describe('McpServersService.toView (via list) — encrypted-header leak guard',
       enabled: false,
       toolAllowlist: ['search'],
       hasHeaders: true,
+      instructions: 'Use search for fresh web facts.',
     });
   });
+
+  it('returns instructions (NON-secret) in the view, null when unset', async () => {
+    const service = buildService([
+      row({ id: 'a', instructions: 'How to use these tools.' }),
+      row({ id: 'b', instructions: null }),
+    ]);
+
+    const [withText, withoutText] = await service.list('ws-1');
+
+    expect(withText.instructions).toBe('How to use these tools.');
+    expect(withoutText.instructions).toBeNull();
+  });
 });

apps/server/src/core/ai-chat/external-mcp/mcp-servers.service.ts

@@ -20,6 +20,9 @@ export interface McpServerView {
   enabled: boolean;
   toolAllowlist: string[] | null;
   hasHeaders: boolean;
+  // Admin-authored prompt guidance (#180). NON-secret, so returned in the view.
+  // Null when no guidance is configured.
+  instructions: string | null;
 }
 
 /**
@@ -56,6 +59,8 @@ export class McpServersService {
       url: dto.url,
       headersEnc,
       toolAllowlist: dto.toolAllowlist ?? null,
+      // Blank/whitespace guidance is normalized to null by the repo.
+      instructions: dto.instructions ?? null,
       enabled: dto.enabled ?? true,
     });
     this.clients.invalidate(workspaceId);
@@ -97,6 +102,8 @@ export class McpServersService {
       headersEnc,
       // undefined => unchanged; [] / value handled by repo (empty => null).
       toolAllowlist: dto.toolAllowlist,
+      // undefined => unchanged; blank => cleared (null) by the repo.
+      instructions: dto.instructions,
       enabled: dto.enabled,
     });
     this.clients.invalidate(workspaceId);
@@ -167,6 +174,7 @@ export class McpServersService {
       enabled: row.enabled,
       toolAllowlist: row.toolAllowlist ?? null,
       hasHeaders: Boolean(row.headersEnc),
+      instructions: row.instructions ?? null,
     };
   }
 }

apps/server/src/core/ai-chat/roles/jsonb-object.spec.ts

@@ -1,30 +0,0 @@
-import { jsonbObject } from '@docmost/db/repos/ai-agent-roles/ai-agent-roles.repo';
-
-/**
- * Unit tests for jsonbObject: the repo helper that encodes a model_config object
- * as a jsonb bind (or null when there is nothing to persist). It is the last
- * line of defence before the column write, so the null-vs-bind decision is what
- * matters here. We assert only null vs non-null because the non-null value is a
- * kysely `sql` template fragment whose internal shape is an implementation
- * detail of the SQL tag.
- */
-describe('jsonbObject', () => {
-  it('returns null for null', () => {
-    expect(jsonbObject(null)).toBeNull();
-  });
-
-  it('returns null for undefined', () => {
-    expect(jsonbObject(undefined)).toBeNull();
-  });
-
-  it('returns null for an empty object (nothing to persist)', () => {
-    expect(jsonbObject({})).toBeNull();
-  });
-
-  it('returns a (non-null) jsonb bind for a non-empty object', () => {
-    const out = jsonbObject({ driver: 'gemini', chatModel: 'gemini-2.0-flash' });
-    // A real sql fragment is produced, never null/undefined.
-    expect(out).not.toBeNull();
-    expect(out).toBeDefined();
-  });
-});

apps/server/src/core/share/share-seo.controller.routing.spec.ts

@@ -0,0 +1,133 @@
+import * as fs from 'node:fs';
+import { ShareSeoController } from './share-seo.controller';
+
+/**
+ * Routing guard for ShareSeoController.getShare (red-team finding #3).
+ *
+ * The SEO route must NOT leak a shared page's <title>/og:title to anonymous
+ * visitors / crawlers when the page is not publicly readable. It previously
+ * called the raw `getShareForPage`, which skips the restricted-ancestor gate, so
+ * a permission-restricted descendant of an includeSubPages share leaked its
+ * title. The fix funnels through `resolveReadableSharePage` (the canonical gate)
+ * AND honours `isSharingAllowed`. These tests pin that routing: a non-readable
+ * page or sharing-disabled space serves the plain SPA index (no title); only a
+ * readable, still-shared page gets meta tags.
+ */
+
+const SECRET_TITLE = 'Restricted Quarterly Numbers';
+const INDEX_HTML = `<!doctype html><html><head><title>App</title><!--meta-tags--></head><body></body></html>`;
+const STREAM_SENTINEL = { __isStream: true } as unknown as fs.ReadStream;
+
+// Stub fs at CALL time (jest.spyOn), NOT module load (jest.mock): the controller
+// transitively pulls bcrypt, whose native module is located by node-gyp-build
+// reading the filesystem at import time — a module-level fs mock breaks that.
+beforeEach(() => {
+  jest.spyOn(fs, 'existsSync').mockReturnValue(true);
+  jest.spyOn(fs, 'readFileSync').mockReturnValue(INDEX_HTML);
+  jest.spyOn(fs, 'createReadStream').mockReturnValue(STREAM_SENTINEL);
+});
+afterEach(() => jest.restoreAllMocks());
+
+function makeRes() {
+  const res: any = {
+    sent: undefined as unknown,
+    type: jest.fn(() => res),
+    send: jest.fn((v: unknown) => {
+      res.sent = v;
+    }),
+  };
+  return res;
+}
+
+function makeController(opts: {
+  resolved: { share: any; page: any } | null;
+  sharingAllowed?: boolean;
+}) {
+  const shareService = {
+    resolveReadableSharePage: jest.fn(async () => opts.resolved),
+    isSharingAllowed: jest.fn(async () => opts.sharingAllowed ?? true),
+    // Must NEVER be used by the SEO path anymore (the bypass is the bug).
+    getShareForPage: jest.fn(async () => {
+      throw new Error('getShareForPage must not be called by the SEO path');
+    }),
+  };
+  const workspaceRepo = {
+    findFirst: async () => ({ id: 'ws-1', settings: {} }),
+  };
+  const environmentService = { isSelfHosted: () => true };
+  const controller = new ShareSeoController(
+    shareService as any,
+    workspaceRepo as any,
+    environmentService as any,
+  );
+  return { controller, shareService };
+}
+
+const req: any = { raw: { headers: { host: 'self' } } };
+
+describe('ShareSeoController.getShare routing (#3 title-leak gate)', () => {
+  it('serves the plain index (NO title) when the page is not publicly readable', async () => {
+    const { controller, shareService } = makeController({ resolved: null });
+    const res = makeRes();
+
+    await controller.getShare(res, req, 'share-key', `slug-pageB`);
+
+    // The restricted-ancestor gate ran; the raw bypass did not.
+    expect(shareService.resolveReadableSharePage).toHaveBeenCalled();
+    expect(shareService.getShareForPage).not.toHaveBeenCalled();
+    // The plain index stream was sent — NOT the title-bearing meta HTML.
+    expect(res.sent).toBe(STREAM_SENTINEL);
+  });
+
+  it('serves the plain index when sharing was disabled at the workspace/space level', async () => {
+    const { controller } = makeController({
+      resolved: {
+        share: { spaceId: 'sp-1', searchIndexing: true },
+        page: { title: SECRET_TITLE },
+      },
+      sharingAllowed: false,
+    });
+    const res = makeRes();
+
+    await controller.getShare(res, req, 'share-key', 'slug-pageB');
+
+    // The plain index stream was sent, so the restricted title never reached
+    // the response (it is only ever interpolated into the meta HTML string).
+    expect(res.sent).toBe(STREAM_SENTINEL);
+    expect(res.sent).not.toBe(SECRET_TITLE);
+  });
+
+  it('injects the title + meta for a readable, still-shared page', async () => {
+    const { controller } = makeController({
+      resolved: {
+        share: { spaceId: 'sp-1', searchIndexing: true },
+        page: { title: 'Public Handbook' },
+      },
+      sharingAllowed: true,
+    });
+    const res = makeRes();
+
+    await controller.getShare(res, req, 'share-key', 'slug-pageA');
+
+    expect(typeof res.sent).toBe('string');
+    expect(res.sent as string).toContain('<title>Public Handbook</title>');
+    expect(res.sent as string).toContain('og:title');
+    // searchIndexing on => crawlable (no noindex).
+    expect(res.sent as string).not.toContain('content="noindex"');
+  });
+
+  it('adds robots=noindex when the share opted out of search indexing', async () => {
+    const { controller } = makeController({
+      resolved: {
+        share: { spaceId: 'sp-1', searchIndexing: false },
+        page: { title: 'Internal Notes' },
+      },
+      sharingAllowed: true,
+    });
+    const res = makeRes();
+
+    await controller.getShare(res, req, 'share-key', 'slug-pageA');
+
+    expect(res.sent as string).toContain('content="noindex"');
+  });
+});

apps/server/src/core/share/share-seo.controller.ts

@@ -63,19 +63,38 @@ export class ShareSeoController {
 
       const pageId = this.extractPageSlugId(pageSlug);
 
-      const share = await this.shareService.getShareForPage(
+      // Funnel through the canonical readable-share boundary (NOT the raw
+      // getShareForPage) so the restricted-ancestor gate runs: a permission-
+      // restricted descendant of an includeSubPages share must NOT leak its
+      // title to anonymous visitors / crawlers (red-team finding #3). null =>
+      // not publicly readable => serve the plain SPA index with no meta.
+      const resolved = await this.shareService.resolveReadableSharePage(
+        undefined,
         pageId,
         workspace.id,
       );
 
-      if (!share) {
+      if (!resolved) {
+        return this.sendIndex(indexFilePath, res);
+      }
+
+      // Honour a workspace/space-level sharing toggle flipped off AFTER this
+      // share was created: the content API gates on isSharingAllowed, so the SEO
+      // path must too or it keeps serving the title for a no-longer-shared page.
+      const sharingAllowed = await this.shareService.isSharingAllowed(
+        workspace.id,
+        resolved.share.spaceId,
+      );
+      if (!sharingAllowed) {
         return this.sendIndex(indexFilePath, res);
       }
 
       const html = fs.readFileSync(indexFilePath, 'utf8');
+      // Title of the PAGE being viewed (server-resolved), and noindex unless the
+      // share opted into search indexing (buildShareMetaHtml injects it).
       let transformedHtml = buildShareMetaHtml(html, {
-        title: share?.sharedPage.title,
-        searchIndexing: share.searchIndexing,
+        title: resolved.page.title,
+        searchIndexing: resolved.share.searchIndexing,
       });
 
       // Deliberate same-origin tracker surface: this is the ONE place where an

apps/server/src/database/jsonb-bind.spec.ts

@@ -0,0 +1,38 @@
+import { jsonbBind } from './utils';
+
+/**
+ * Unit tests for jsonbBind: THE shared helper that encodes a JS array/object as
+ * a jsonb bind (or null when there is nothing to persist). It is the last line
+ * of defence before a jsonb column write, so the null-vs-bind decision is what
+ * matters here. We assert only null vs non-null because the non-null value is a
+ * kysely `sql` template fragment whose internal shape is an implementation
+ * detail of the SQL tag (the `::text::jsonb` double-encoding fix is verified
+ * end-to-end by the repo integration specs, where a real DB round-trip can
+ * actually observe `jsonb_typeof`).
+ */
+describe('jsonbBind', () => {
+  it('returns null for null / undefined', () => {
+    expect(jsonbBind(null)).toBeNull();
+    expect(jsonbBind(undefined)).toBeNull();
+  });
+
+  it('returns null for an empty array (nothing to persist)', () => {
+    expect(jsonbBind([])).toBeNull();
+  });
+
+  it('returns null for an empty object (nothing to persist)', () => {
+    expect(jsonbBind({})).toBeNull();
+  });
+
+  it('returns a (non-null) bind for a non-empty array', () => {
+    const out = jsonbBind(['search', 'crawl']);
+    expect(out).not.toBeNull();
+    expect(out).toBeDefined();
+  });
+
+  it('returns a (non-null) bind for a non-empty object', () => {
+    const out = jsonbBind({ driver: 'gemini', chatModel: 'gemini-2.0-flash' });
+    expect(out).not.toBeNull();
+    expect(out).toBeDefined();
+  });
+});

apps/server/src/database/migrations/20260625T120000-ai-mcp-servers-instructions.ts

@@ -0,0 +1,19 @@
+import { type Kysely } from 'kysely';
+
+export async function up(db: Kysely<any>): Promise<void> {
+  // Per-server, admin-authored instruction text injected into the agent system
+  // prompt next to the server's tool descriptions (#180). NON-secret (unlike
+  // headers_enc): it IS returned in admin views/forms. Nullable: a server may
+  // have no guidance. Trusted text — it goes inside the prompt safety sandwich.
+  await db.schema
+    .alterTable('ai_mcp_servers')
+    .addColumn('instructions', 'text', (col) => col)
+    .execute();
+}
+
+export async function down(db: Kysely<any>): Promise<void> {
+  await db.schema
+    .alterTable('ai_mcp_servers')
+    .dropColumn('instructions')
+    .execute();
+}

apps/server/src/database/migrations/20260626T120000-ai-chat-message-status.ts

@@ -0,0 +1,18 @@
+import { type Kysely } from 'kysely';
+
+export async function up(db: Kysely<any>): Promise<void> {
+  // Step-granular durability for the assistant turn (#183). The assistant row is
+  // now created UPFRONT (status 'streaming') and UPDATEd as each step completes,
+  // so a process death mid-turn no longer loses the whole answer. The column is
+  // NULLABLE on purpose: rows written before this migration carry NULL, which the
+  // app treats as 'completed' (a settled, pre-status message). Values written by
+  // the app: 'streaming' | 'completed' | 'error' | 'aborted'.
+  await db.schema
+    .alterTable('ai_chat_messages')
+    .addColumn('status', 'text', (col) => col)
+    .execute();
+}
+
+export async function down(db: Kysely<any>): Promise<void> {
+  await db.schema.alterTable('ai_chat_messages').dropColumn('status').execute();
+}

apps/server/src/database/repos/ai-agent-roles/ai-agent-roles.repo.spec.ts

@@ -35,7 +35,13 @@ describe('AiAgentRoleRepo.findLiveEnabled', () => {
 
     const result = await repo.findLiveEnabled('r-1', 'ws-1');
 
-    expect(result).toBe(role);
+    // The repo normalizes the row (modelConfig parse), so it returns a COPY, not
+    // the same reference; assert the row's fields are carried through.
+    expect(result).toMatchObject({
+      id: 'r-1',
+      workspaceId: 'ws-1',
+      enabled: true,
+    });
     expect(db.selectFrom).toHaveBeenCalledWith('aiAgentRoles');
     // Every security filter must be present.
     expect(where).toHaveBeenCalledWith('id', '=', 'r-1');

apps/server/src/database/repos/ai-agent-roles/ai-agent-roles.repo.ts

@@ -1,8 +1,7 @@
 import { Injectable } from '@nestjs/common';
 import { InjectKysely } from 'nestjs-kysely';
-import { sql } from 'kysely';
 import { KyselyDB, KyselyTransaction } from '../../types/kysely.types';
-import { dbOrTx } from '../../utils';
+import { dbOrTx, jsonbBind, parseJsonbValue } from '../../utils';
 import { AiAgentRole } from '@docmost/db/types/entity.types';
 
 /** The jsonb shape persisted in `model_config` (loosely typed for the column). */
@@ -23,13 +22,14 @@ export class AiAgentRoleRepo {
     id: string,
     workspaceId: string,
   ): Promise<AiAgentRole | undefined> {
-    return this.db
+    const row = await this.db
       .selectFrom('aiAgentRoles')
       .selectAll('aiAgentRoles')
       .where('id', '=', id)
       .where('workspaceId', '=', workspaceId)
       .where('deletedAt', 'is', null)
       .executeTakeFirst();
+    return row ? normalizeRow(row) : row;
   }
 
   /**
@@ -45,7 +45,7 @@ export class AiAgentRoleRepo {
     id: string,
     workspaceId: string,
   ): Promise<AiAgentRole | undefined> {
-    return this.db
+    const row = await this.db
       .selectFrom('aiAgentRoles')
       .selectAll('aiAgentRoles')
       .where('id', '=', id)
@@ -53,17 +53,19 @@ export class AiAgentRoleRepo {
       .where('deletedAt', 'is', null)
       .where('enabled', '=', true)
       .executeTakeFirst();
+    return row ? normalizeRow(row) : row;
   }
 
   /** All live roles for the workspace (management list + chat picker). */
   async listByWorkspace(workspaceId: string): Promise<AiAgentRole[]> {
-    return this.db
+    const rows = await this.db
       .selectFrom('aiAgentRoles')
       .selectAll('aiAgentRoles')
       .where('workspaceId', '=', workspaceId)
       .where('deletedAt', 'is', null)
       .orderBy('createdAt', 'asc')
       .execute();
+    return rows.map(normalizeRow);
   }
 
   async insert(
@@ -83,7 +85,7 @@ export class AiAgentRoleRepo {
     trx?: KyselyTransaction,
   ): Promise<AiAgentRole> {
     const db = dbOrTx(this.db, trx);
-    return db
+    const row = await db
       .insertInto('aiAgentRoles')
       .values({
         workspaceId: values.workspaceId,
@@ -92,7 +94,11 @@ export class AiAgentRoleRepo {
         emoji: values.emoji ?? null,
         description: values.description ?? null,
         instructions: values.instructions,
-        modelConfig: jsonbObject(values.modelConfig),
+        // Cast: the generated `model_config` column type is the broad JsonValue
+        // union, which the concrete RawBuilder<Record> is not structurally
+        // assignable to (same reason the old jsonbObject cast to any).
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        modelConfig: jsonbBind(values.modelConfig) as any,
         enabled: values.enabled ?? true,
         autoStart: values.autoStart ?? true,
         // Empty string is treated as "no custom text" => null.
@@ -100,6 +106,7 @@ export class AiAgentRoleRepo {
       })
       .returningAll()
       .executeTakeFirst();
+    return normalizeRow(row);
   }
 
   async update(
@@ -127,7 +134,7 @@ export class AiAgentRoleRepo {
     if (patch.description !== undefined) set.description = patch.description;
     if (patch.instructions !== undefined) set.instructions = patch.instructions;
     if (patch.modelConfig !== undefined) {
-      set.modelConfig = jsonbObject(patch.modelConfig);
+      set.modelConfig = jsonbBind(patch.modelConfig);
     }
     if (patch.enabled !== undefined) set.enabled = patch.enabled;
     if (patch.autoStart !== undefined) set.autoStart = patch.autoStart;
@@ -163,16 +170,36 @@ export class AiAgentRoleRepo {
 }
 
 /**
- * Encode an object as a jsonb bind for the `model_config` column. The postgres
- * driver would otherwise need an explicit cast; bind the JSON text and cast it.
- * Returns null for null/undefined/empty objects. Cast to `any` because the
- * generated column type is the broad `JsonValue` union, which a concrete object
- * type is not structurally assignable to.
+ * Parse the `model_config` value read from the DB into the object the entity
+ * type promises. Rows written by the old double-encoding bind (`::jsonb` instead
+ * of `::text::jsonb`) round-trip as a JSON STRING, so the driver hands back e.g.
+ * `'{"driver":"gemini"}'` rather than an object; the read-path check
+ * `typeof cfg === 'object'` then failed and the model override was SILENTLY
+ * dropped (the role fell back to the default model). Be tolerant: a JSON string
+ * is parsed; an already-parsed object passes through; null / a non-object (incl.
+ * an array) / unparseable value becomes null (= no override). This self-heals
+ * already-corrupted rows on read, no migration required.
  */
-export function jsonbObject(value: ModelConfigValue | undefined) {
-  if (value === null || value === undefined || Object.keys(value).length === 0) {
-    return null;
-  }
-  // eslint-disable-next-line @typescript-eslint/no-explicit-any
-  return sql`${JSON.stringify(value)}::jsonb` as any;
+export function parseModelConfig(
+  value: unknown,
+): Record<string, unknown> | null {
+  // Shape guard only; the legacy double-encoding self-heal lives in
+  // parseJsonbValue (database/utils.ts).
+  return parseJsonbValue(
+    value,
+    (v): v is Record<string, unknown> =>
+      v !== null && typeof v === 'object' && !Array.isArray(v),
+  );
+}
+
+/** Normalize a DB row so `modelConfig` is always an object or null. The cast
+ *  bridges parseModelConfig's concrete `Record | null` to the column's broad
+ *  generated `JsonValue` type (an object is a valid JsonValue at runtime). */
+function normalizeRow(row: AiAgentRole): AiAgentRole {
+  return {
+    ...row,
+    modelConfig: parseModelConfig(
+      row.modelConfig,
+    ) as AiAgentRole['modelConfig'],
+  };
 }

apps/server/src/database/repos/ai-agent-roles/parse-model-config.spec.ts

@@ -0,0 +1,46 @@
+import { parseModelConfig } from './ai-agent-roles.repo';
+
+/**
+ * Unit tests for parseModelConfig: the read-side normalizer that repairs the
+ * jsonb double-encoding regression on `model_config`. Rows written by the old
+ * `::jsonb` bind round-trip as a JSON STRING, which the read path's
+ * `typeof === 'object'` check rejected — silently dropping the model override.
+ * parseModelConfig accepts an already-parsed object, parses a legacy JSON
+ * string, and rejects everything that is not an object (null = no override).
+ */
+describe('parseModelConfig', () => {
+  it('passes an already-parsed object through', () => {
+    expect(parseModelConfig({ driver: 'gemini' })).toEqual({
+      driver: 'gemini',
+    });
+  });
+
+  it('parses a legacy double-encoded JSON string into an object', () => {
+    expect(parseModelConfig('{"driver":"gemini","chatModel":"x"}')).toEqual({
+      driver: 'gemini',
+      chatModel: 'x',
+    });
+  });
+
+  it('returns null for null / undefined', () => {
+    expect(parseModelConfig(null)).toBeNull();
+    expect(parseModelConfig(undefined)).toBeNull();
+  });
+
+  it('returns null for a non-object JSON value (string/number/array)', () => {
+    expect(parseModelConfig('"justastring"')).toBeNull();
+    expect(parseModelConfig('42')).toBeNull();
+    // An array is an object in JS but not a valid model_config shape.
+    expect(parseModelConfig('["a","b"]')).toBeNull();
+    expect(parseModelConfig(['a', 'b'])).toBeNull();
+  });
+
+  it('returns null for an unparseable string', () => {
+    expect(parseModelConfig('not json at all')).toBeNull();
+  });
+
+  it('returns null for a raw non-object primitive', () => {
+    expect(parseModelConfig(42 as unknown)).toBeNull();
+    expect(parseModelConfig(true as unknown)).toBeNull();
+  });
+});

apps/server/src/database/repos/ai-chat/ai-chat-message.repo.ts

@@ -1,4 +1,4 @@
-import { Injectable } from '@nestjs/common';
+import { Injectable, Logger } from '@nestjs/common';
 import { InjectKysely } from 'nestjs-kysely';
 import { KyselyDB, KyselyTransaction } from '../../types/kysely.types';
 import { dbOrTx } from '../../utils';
@@ -9,8 +9,24 @@ import {
 import { PaginationOptions } from '@docmost/db/pagination/pagination-options';
 import { executeWithCursorPagination } from '@docmost/db/pagination/cursor-pagination';
 
+// Crash-recovery sweep recency threshold (#183 review): a 'streaming' row is
+// only swept to 'aborted' once it has been UNTOUCHED for this long. A live turn
+// bumps `updatedAt` on every step (well under this window), so its row never
+// matches; only a turn whose process truly died (no step update for >threshold)
+// is swept. Chosen safely ABOVE the longest realistic turn so a fresh replica's
+// boot-sweep can never abort a turn another replica is actively streaming
+// (multi-instance deploy).
+const SWEEP_STREAMING_STALE_MS = 10 * 60 * 1000; // 10 minutes
+
+// Hard upper bound on the rows materialized by `findAllByChat` (export path).
+// A generous cap so a pathologically huge chat cannot load an unbounded result
+// into memory; far above any realistic transcript length.
+const FIND_ALL_BY_CHAT_LIMIT = 5000;
+
 @Injectable()
 export class AiChatMessageRepo {
+  private readonly logger = new Logger(AiChatMessageRepo.name);
+
   constructor(@InjectKysely() private readonly db: KyselyDB) {}
 
   // The `tsv` column is a trigger-maintained tsvector used only for
@@ -25,6 +41,7 @@ export class AiChatMessageRepo {
     'content',
     'toolCalls',
     'metadata',
+    'status',
     'createdAt',
     'updatedAt',
     'deletedAt',
@@ -60,6 +77,46 @@ export class AiChatMessageRepo {
     });
   }
 
+  // Load ALL (non-deleted) messages of a chat in ascending chronological order
+  // (oldest -> newest), unpaginated. Used by the server-side Markdown export
+  // (#183), where the DB is the single source of truth and the whole transcript
+  // must be rendered in one pass (findByChat is cursor-paginated and would only
+  // return the first page).
+  //
+  // Hard-capped at FIND_ALL_BY_CHAT_LIMIT rows (a generous bound, far above any
+  // realistic transcript) so exporting a pathologically huge chat cannot
+  // materialize an unbounded result set in memory.
+  async findAllByChat(
+    chatId: string,
+    workspaceId: string,
+    // Injectable for tests so truncation can be exercised on a modest volume.
+    limit: number = FIND_ALL_BY_CHAT_LIMIT,
+  ): Promise<AiChatMessage[]> {
+    // Fetch newest-first (+1 to DETECT truncation), so on overflow we keep the
+    // NEWEST `limit` messages — the recent conversation matters most for an
+    // export — rather than silently dropping the tail (#183 review). Reverse back
+    // to chronological for rendering, like findRecent.
+    const rows = await this.db
+      .selectFrom('aiChatMessages')
+      .select(this.baseFields)
+      .where('chatId', '=', chatId)
+      .where('workspaceId', '=', workspaceId)
+      .where('deletedAt', 'is', null)
+      .orderBy('createdAt', 'desc')
+      .orderBy('id', 'desc')
+      .limit(limit + 1)
+      .execute();
+
+    if (rows.length > limit) {
+      rows.length = limit; // keep the newest `limit` (rows are newest-first here)
+      this.logger.warn(
+        `Chat ${chatId} export truncated to the newest ${limit} messages ` +
+          `(older messages omitted).`,
+      );
+    }
+    return rows.reverse();
+  }
+
   // Load the most RECENT `limit` messages for a chat and return them in
   // ascending chronological order (oldest -> newest), as the model expects.
   // `findByChat` returns the FIRST page ASC (the OLDEST messages), which loses
@@ -96,4 +153,68 @@ export class AiChatMessageRepo {
       .returning(this.baseFields)
       .executeTakeFirst();
   }
+
+  /**
+   * Update a single message in place by id + workspace (#183 step-granular
+   * durability). The assistant row is created UPFRONT (status 'streaming') and
+   * patched as each step completes, then finalized once on the terminal status.
+   * `updatedAt` is always bumped. Returns the updated row (baseFields) or
+   * undefined when no row matched (e.g. a foreign workspace / deleted row).
+   */
+  async update(
+    id: string,
+    workspaceId: string,
+    patch: Partial<{
+      content: string | null;
+      toolCalls: unknown;
+      metadata: unknown;
+      status: string | null;
+    }>,
+    opts?: { onlyIfStreaming?: boolean; trx?: KyselyTransaction },
+  ): Promise<AiChatMessage | undefined> {
+    const db = dbOrTx(this.db, opts?.trx);
+    let query = db
+      .updateTable('aiChatMessages')
+      .set({ ...(patch as Record<string, unknown>), updatedAt: new Date() })
+      .where('id', '=', id)
+      .where('workspaceId', '=', workspaceId);
+    // Concurrency guard (#183 review): a per-step 'streaming' update must NEVER
+    // overwrite a row the terminal callback already finalized. onStepFinish
+    // fires the streaming update fire-and-forget, so its UPDATE can land AFTER
+    // finalize on a DIFFERENT pool connection (commit order is not guaranteed).
+    // Scoping the streaming update to rows STILL in 'streaming' makes a late
+    // update a no-op once the row is completed/error/aborted — regardless of
+    // commit order. The terminal finalize runs WITHOUT this guard so it always
+    // wins.
+    if (opts?.onlyIfStreaming) {
+      query = query.where('status', '=', 'streaming');
+    }
+    return query.returning(this.baseFields).executeTakeFirst();
+  }
+
+  /**
+   * Crash-recovery sweep (#183): flip every assistant row still left in the
+   * 'streaming' state (a turn that died mid-write before reaching a terminal
+   * status) to 'aborted'. Run once on server start. Returns the number of rows
+   * swept so the caller can log it. Workspace-wide on purpose — a crash can have
+   * dangling streaming rows across any workspace.
+   *
+   * Bounded by recency (#183 review): only rows UNTOUCHED for
+   * SWEEP_STREAMING_STALE_MS are swept. A live turn bumps `updatedAt` on every
+   * step, so an actively-streaming row never matches; this prevents a fresh
+   * replica's boot-sweep from aborting a turn another replica is still streaming
+   * in a multi-instance deploy.
+   */
+  async sweepStreaming(trx?: KyselyTransaction): Promise<number> {
+    const db = dbOrTx(this.db, trx);
+    const staleBefore = new Date(Date.now() - SWEEP_STREAMING_STALE_MS);
+    const rows = await db
+      .updateTable('aiChatMessages')
+      .set({ status: 'aborted', updatedAt: new Date() })
+      .where('status', '=', 'streaming')
+      .where('updatedAt', '<', staleBefore)
+      .returning('id')
+      .execute();
+    return rows.length;
+  }
 }

apps/server/src/database/repos/ai-chat/ai-mcp-server.repo.spec.ts

@@ -1,4 +1,4 @@
-import { parseToolAllowlist } from './ai-mcp-server.repo';
+import { parseToolAllowlist, blankToNull } from './ai-mcp-server.repo';
 
 /**
  * The `tool_allowlist` jsonb column historically round-trips as a JSON STRING
@@ -10,7 +10,10 @@ import { parseToolAllowlist } from './ai-mcp-server.repo';
  */
 describe('parseToolAllowlist', () => {
   it('passes a real string array through unchanged', () => {
-    expect(parseToolAllowlist(['search', 'crawl'])).toEqual(['search', 'crawl']);
+    expect(parseToolAllowlist(['search', 'crawl'])).toEqual([
+      'search',
+      'crawl',
+    ]);
   });
 
   it('parses a JSON-string array (the double-encoded read) into an array', () => {
@@ -46,3 +49,26 @@ describe('parseToolAllowlist', () => {
     expect(parseToolAllowlist(true as unknown)).toBeNull();
   });
 });
+
+/**
+ * `blankToNull` normalizes the per-server `instructions` free text before it is
+ * stored (#180): a missing/blank/whitespace-only value becomes null (so an empty
+ * guide is never persisted), any other value is trimmed.
+ */
+describe('blankToNull', () => {
+  it('returns null for null / undefined', () => {
+    expect(blankToNull(null)).toBeNull();
+    expect(blankToNull(undefined)).toBeNull();
+  });
+
+  it('returns null for an empty / whitespace-only string', () => {
+    expect(blankToNull('')).toBeNull();
+    expect(blankToNull('   ')).toBeNull();
+    expect(blankToNull('\n\t ')).toBeNull();
+  });
+
+  it('trims and returns a non-blank string', () => {
+    expect(blankToNull('  use the search tool  ')).toBe('use the search tool');
+    expect(blankToNull('guide')).toBe('guide');
+  });
+});

apps/server/src/database/repos/ai-chat/ai-mcp-server.repo.ts

@@ -1,10 +1,11 @@
-import { Injectable } from '@nestjs/common';
+import { Injectable, Logger } from '@nestjs/common';
 import { InjectKysely } from 'nestjs-kysely';
-import { sql } from 'kysely';
 import { KyselyDB, KyselyTransaction } from '../../types/kysely.types';
-import { dbOrTx } from '../../utils';
+import { dbOrTx, jsonbBind, parseJsonbValue } from '../../utils';
 import { AiMcpServer } from '@docmost/db/types/entity.types';
 
+const logger = new Logger('AiMcpServerRepo');
+
 /**
  * Repository for per-workspace external MCP servers the agent may use (§5.4).
  *
@@ -60,6 +61,8 @@ export class AiMcpServerRepo {
       url: string;
       headersEnc?: string | null;
       toolAllowlist?: string[] | null;
+      // Admin-authored prompt guidance; blank/whitespace normalizes to null.
+      instructions?: string | null;
       enabled?: boolean;
     },
     trx?: KyselyTransaction,
@@ -75,7 +78,9 @@ export class AiMcpServerRepo {
         headersEnc: values.headersEnc ?? null,
         // jsonb column: the postgres driver would otherwise encode a JS array as
         // a Postgres array literal. Bind the JSON text and cast it to jsonb.
-        toolAllowlist: jsonbArray(values.toolAllowlist),
+        toolAllowlist: jsonbBind(values.toolAllowlist),
+        // Plain text column: blank/whitespace-only guidance is stored as null.
+        instructions: blankToNull(values.instructions),
         enabled: values.enabled ?? true,
       })
       .returningAll()
@@ -93,6 +98,8 @@ export class AiMcpServerRepo {
       headersEnc?: string | null;
       // undefined => leave unchanged; null => clear; string[] => set.
       toolAllowlist?: string[] | null;
+      // undefined => leave unchanged; null/blank => clear; string => set.
+      instructions?: string | null;
       enabled?: boolean;
     },
     trx?: KyselyTransaction,
@@ -104,7 +111,11 @@ export class AiMcpServerRepo {
     if (patch.url !== undefined) set.url = patch.url;
     if (patch.headersEnc !== undefined) set.headersEnc = patch.headersEnc;
     if (patch.toolAllowlist !== undefined) {
-      set.toolAllowlist = jsonbArray(patch.toolAllowlist);
+      set.toolAllowlist = jsonbBind(patch.toolAllowlist);
+    }
+    if (patch.instructions !== undefined) {
+      // Blank/whitespace-only guidance clears the column (stored as null).
+      set.instructions = blankToNull(patch.instructions);
     }
     if (patch.enabled !== undefined) set.enabled = patch.enabled;
     await db
@@ -130,57 +141,49 @@ export class AiMcpServerRepo {
 }
 
 /**
- * Encode a string[] as a jsonb bind for the `tool_allowlist` column. Passing a
- * plain JS array to the postgres driver would serialize it as a Postgres array
- * literal (incompatible with jsonb), so we bind the JSON text and cast it.
- *
- * The cast is `::text::jsonb`, NOT `::jsonb`: if the parameter is bound straight
- * to a jsonb cast, node-postgres infers its type as jsonb and JSON-stringifies
- * the (already-JSON) string a SECOND time, so the column ends up holding a jsonb
- * STRING SCALAR (`"[\"a\"]"`) instead of a jsonb ARRAY. Forcing the param through
- * `::text` first binds it as text (sent verbatim), and `::jsonb` then parses it
- * into a real array. (`normalizeRow` below repairs rows written the old way.)
- *
- * Returns null for null/empty arrays (an empty allowlist means "no restriction"
- * is not intended — callers pass null to clear; an empty array is normalized to
- * null here so it never round-trips as `[]`).
+ * Normalize an optional free-text field to a stored value: a missing/blank/
+ * whitespace-only string becomes null (so an "empty" guide is never persisted),
+ * any other string is trimmed. Returns null for null/undefined input.
  */
-function jsonbArray(value: string[] | null | undefined) {
-  if (value === null || value === undefined || value.length === 0) {
-    return null;
-  }
-  // Typed as string[] so it is assignable to the toolAllowlist column.
-  return sql<string[]>`${JSON.stringify(value)}::text::jsonb`;
+export function blankToNull(value: string | null | undefined): string | null {
+  if (value == null) return null;
+  const trimmed = value.trim();
+  return trimmed.length > 0 ? trimmed : null;
 }
 
 /**
  * Parse the `toolAllowlist` value read from the DB into the `string[] | null`
  * the entity type promises. The jsonb column historically round-trips as a JSON
- * STRING (rows written by the old double-encoding `jsonbArray`, see above), so
- * the driver hands back a string like `'["a","b"]'` rather than an array. Be
- * tolerant: an already-parsed array passes through; a JSON string is parsed; null
- * / a non-array / unparseable value becomes null (unrestricted).
+ * STRING (rows written by the old double-encoding bind before the `::text::jsonb`
+ * fix), so the driver hands back a string like `'["a","b"]'` rather than an
+ * array. Be tolerant: normalize a JSON string to its value, then accept it only
+ * if it is an array of strings; null / a non-array / unparseable value / an
+ * array with a non-string element all become null (unrestricted).
  */
 export function parseToolAllowlist(value: unknown): string[] | null {
-  if (value == null) return null;
-  if (Array.isArray(value)) {
-    return value.every((v) => typeof v === 'string') ? (value as string[]) : null;
-  }
-  if (typeof value === 'string') {
-    try {
-      const parsed = JSON.parse(value);
-      return Array.isArray(parsed) &&
-        parsed.every((v) => typeof v === 'string')
-        ? (parsed as string[])
-        : null;
-    } catch {
-      return null;
-    }
-  }
-  return null;
+  // Shape guard only; the legacy double-encoding self-heal lives in
+  // parseJsonbValue (database/utils.ts).
+  return parseJsonbValue(
+    value,
+    (v): v is string[] =>
+      Array.isArray(v) && v.every((x) => typeof x === 'string'),
+  );
 }
 
-/** Normalize a DB row so `toolAllowlist` is always `string[] | null`. */
+/**
+ * Normalize a DB row so `toolAllowlist` is always `string[] | null`.
+ *
+ * FAIL-OPEN logging: a stored value that is present but cannot be parsed into a
+ * string[] (corrupt JSON, a non-array, non-string elements) degrades to `null` =
+ * "no restriction", so the agent silently gets ALL of the server's tools. Log
+ * one line (server id only, never the contents) so that widening is not silent.
+ */
 function normalizeRow(row: AiMcpServer): AiMcpServer {
-  return { ...row, toolAllowlist: parseToolAllowlist(row.toolAllowlist) };
+  const parsed = parseToolAllowlist(row.toolAllowlist);
+  if (parsed === null && row.toolAllowlist != null) {
+    logger.warn(
+      `Corrupt tool_allowlist for MCP server ${row.id}; ignoring it (no tool restriction applied)`,
+    );
+  }
+  return { ...row, toolAllowlist: parsed };
 }

apps/server/src/database/types/ai-mcp-servers.types.ts

@@ -20,8 +20,15 @@ export interface AiMcpServers {
   // Encrypted JSON of the auth headers. Nullable (a server may need no auth).
   headersEnc: string | null;
   // Optional allowlist of remote tool names to expose; null = expose all.
-  // Stored as jsonb; reads come back as a string[] from the postgres driver.
+  // Stored as jsonb. The postgres driver may return a JSON string for legacy
+  // double-encoded rows; `AiMcpServerRepo` normalizes every read to
+  // `string[] | null` via `parseToolAllowlist`.
   toolAllowlist: string[] | null;
+  // Admin-authored guidance ("how/when to use this server's tools") injected
+  // into the agent system prompt (#180). Unlike `headersEnc` this is NON-secret
+  // and IS returned in admin views/forms. Plain text column (no jsonb). Null =
+  // no guidance. Trusted text — it goes inside the prompt safety sandwich.
+  instructions: string | null;
   enabled: Generated<boolean>;
   createdAt: Generated<Timestamp>;
   updatedAt: Generated<Timestamp>;

apps/server/src/database/types/db.d.ts

@@ -620,6 +620,10 @@ export interface AiChatMessages {
   content: string | null;
   toolCalls: Json | null;
   metadata: Json | null;
+  // Turn lifecycle status (#183): 'streaming' | 'completed' | 'error' |
+  // 'aborted'. NULL on rows written before the status column existed; the app
+  // treats NULL as 'completed' (a settled, pre-status message).
+  status: string | null;
   tsv: string | null;
   createdAt: Generated<Timestamp>;
   updatedAt: Generated<Timestamp>;

apps/server/src/database/utils.ts

@@ -1,3 +1,4 @@
+import { sql, RawBuilder } from 'kysely';
 import { KyselyDB, KyselyTransaction } from './types/kysely.types';
 
 /*
@@ -31,3 +32,61 @@ export function dbOrTx(
     return db; // Use normal database instance
   }
 }
+
+/**
+ * Bind a JS array/object as a `jsonb` column value, working around a postgres
+ * driver double-encoding quirk. THE single implementation — repos that persist
+ * jsonb (`tool_allowlist`, `model_config`, ...) call this instead of re-deriving
+ * the cast.
+ *
+ * THE QUIRK: with the `kysely-postgres-js` / postgres.js driver, casting a bound
+ * parameter straight to `::jsonb` makes the driver infer the param type as jsonb
+ * and JSON-stringify the (already-JSON) text a SECOND time, so the column ends
+ * up holding a jsonb STRING SCALAR (`"[\"a\"]"` / `"{\"k\":1}"`) instead of a
+ * real jsonb array/object. Read paths then see a string, not the structure, and
+ * silently fall back (an allowlist becomes "unrestricted", a model override is
+ * ignored). Forcing the param through `::text` first binds it as text (sent
+ * verbatim); `::jsonb` then parses it into a real array/object. Read-side
+ * parsers repair rows written the old buggy way without a migration.
+ *
+ * Returns `null` for null/undefined and for "empty" values (an empty array, or
+ * an object with no own enumerable keys) — callers treat empty as "clear/unset",
+ * so an empty allowlist/config never round-trips as `[]`/`{}`.
+ */
+export function jsonbBind<T>(
+  value: T | null | undefined,
+): RawBuilder<T> | null {
+  if (value === null || value === undefined) return null;
+  if (Array.isArray(value)) {
+    if (value.length === 0) return null;
+  } else if (typeof value === 'object') {
+    if (Object.keys(value as object).length === 0) return null;
+  }
+  return sql<T>`${JSON.stringify(value)}::text::jsonb`;
+}
+
+/**
+ * READ-side counterpart to {@link jsonbBind}: tolerantly decode a jsonb value
+ * read back from the DB and validate its shape with `guard`. THE single place
+ * the legacy double-encoding self-heal lives, so repos keep only a type-guard.
+ *
+ * A row written by the old `::jsonb` bind round-trips as a JSON STRING (see the
+ * quirk in jsonbBind), so the driver hands back e.g. `'["a"]'` / `'{"k":1}'`
+ * rather than the structure. This parses such a string once, then applies the
+ * caller's `guard`. Returns `null` for null / an unparseable string / a value
+ * the guard rejects (so a corrupt or wrong-shaped value degrades to "unset").
+ */
+export function parseJsonbValue<T>(
+  value: unknown,
+  guard: (v: unknown) => v is T,
+): T | null {
+  let v: unknown = value;
+  if (typeof v === 'string') {
+    try {
+      v = JSON.parse(v); // legacy double-encoded read
+    } catch {
+      return null;
+    }
+  }
+  return guard(v) ? v : null;
+}

apps/server/test/integration/ai-agent-roles-repo.int-spec.ts

@@ -1,4 +1,5 @@
-import { Kysely } from 'kysely';
+import { Kysely, sql } from 'kysely';
+import { randomUUID } from 'node:crypto';
 import { AiAgentRoleRepo } from '@docmost/db/repos/ai-agent-roles/ai-agent-roles.repo';
 import { getTestDb, destroyTestDb, createWorkspace } from './db';
 
@@ -25,8 +26,16 @@ describe('AiAgentRoleRepo isolation + partial unique index [integration]', () =>
   });
 
   it('findById / listByWorkspace exclude soft-deleted rows', async () => {
-    const live = await repo.insert({ workspaceId: w1, name: 'Live', instructions: 'x' });
-    const dead = await repo.insert({ workspaceId: w1, name: 'Dead', instructions: 'x' });
+    const live = await repo.insert({
+      workspaceId: w1,
+      name: 'Live',
+      instructions: 'x',
+    });
+    const dead = await repo.insert({
+      workspaceId: w1,
+      name: 'Dead',
+      instructions: 'x',
+    });
     await repo.softDelete(dead.id, w1);
 
     expect(await repo.findById(live.id, w1)).toBeDefined();
@@ -38,7 +47,11 @@ describe('AiAgentRoleRepo isolation + partial unique index [integration]', () =>
   });
 
   it('findById of a W2 role from W1 context returns undefined (tenant isolation)', async () => {
-    const w2role = await repo.insert({ workspaceId: w2, name: 'W2Role', instructions: 'x' });
+    const w2role = await repo.insert({
+      workspaceId: w2,
+      name: 'W2Role',
+      instructions: 'x',
+    });
 
     expect(await repo.findById(w2role.id, w2)).toBeDefined();
     // Same id, wrong workspace context -> not visible.
@@ -58,21 +71,100 @@ describe('AiAgentRoleRepo isolation + partial unique index [integration]', () =>
   });
 
   it('same name is reusable after softDelete (partial unique index WHERE deleted_at IS NULL)', async () => {
-    const first = await repo.insert({ workspaceId: w1, name: 'Reusable', instructions: 'x' });
+    const first = await repo.insert({
+      workspaceId: w1,
+      name: 'Reusable',
+      instructions: 'x',
+    });
     await repo.softDelete(first.id, w1);
 
     // Now inserting the same name must succeed because the soft-deleted row is
     // excluded from the partial unique index.
-    const second = await repo.insert({ workspaceId: w1, name: 'Reusable', instructions: 'x' });
+    const second = await repo.insert({
+      workspaceId: w1,
+      name: 'Reusable',
+      instructions: 'x',
+    });
     expect(second.id).toBeDefined();
     expect(second.id).not.toBe(first.id);
   });
 
   it('same name in W1 and W2 is allowed (unique is per-workspace)', async () => {
-    const a = await repo.insert({ workspaceId: w1, name: 'CrossTenant', instructions: 'x' });
-    const b = await repo.insert({ workspaceId: w2, name: 'CrossTenant', instructions: 'x' });
+    const a = await repo.insert({
+      workspaceId: w1,
+      name: 'CrossTenant',
+      instructions: 'x',
+    });
+    const b = await repo.insert({
+      workspaceId: w2,
+      name: 'CrossTenant',
+      instructions: 'x',
+    });
     expect(a.id).toBeDefined();
     expect(b.id).toBeDefined();
     expect(a.id).not.toBe(b.id);
   });
+
+  // model_config jsonb round-trip (issue #173 §1): the same double-encoding bug
+  // PR #172 fixed for tool_allowlist lived in jsonbObject. A DB round-trip is the
+  // only way to observe it — the write must land as a real jsonb OBJECT, and a
+  // legacy string-scalar row must self-heal on read (else the model override is
+  // silently dropped and the role falls back to the default model).
+  const jsonbTypeof = async (id: string): Promise<string | null> => {
+    const res = await sql<{ t: string | null }>`
+      SELECT jsonb_typeof(model_config) AS t
+      FROM ai_agent_roles WHERE id = ${id}
+    `.execute(db);
+    return res.rows[0]?.t ?? null;
+  };
+
+  it('insert stores model_config as a jsonb OBJECT and reads it back as an object', async () => {
+    const role = await repo.insert({
+      workspaceId: w1,
+      name: `Model-${randomUUID()}`,
+      instructions: 'x',
+      modelConfig: { driver: 'gemini', chatModel: 'gemini-2.0-flash' },
+    });
+    expect(await jsonbTypeof(role.id)).toBe('object');
+    // The returned row is already normalized to an object.
+    expect(role.modelConfig).toEqual({
+      driver: 'gemini',
+      chatModel: 'gemini-2.0-flash',
+    });
+    const found = await repo.findById(role.id, w1);
+    expect(found?.modelConfig).toEqual({
+      driver: 'gemini',
+      chatModel: 'gemini-2.0-flash',
+    });
+  });
+
+  it('an empty model_config is normalized to null (no override)', async () => {
+    const role = await repo.insert({
+      workspaceId: w1,
+      name: `Empty-${randomUUID()}`,
+      instructions: 'x',
+      modelConfig: {},
+    });
+    // The column is SQL NULL, so jsonb_typeof returns SQL NULL (JS null).
+    expect(await jsonbTypeof(role.id)).toBeNull();
+    expect((await repo.findById(role.id, w1))?.modelConfig).toBeNull();
+  });
+
+  it('repairs a legacy double-encoded (string scalar) model_config on read', async () => {
+    const id = randomUUID();
+    // Seed the corrupt string-scalar shape the old `::jsonb` bind produced.
+    await sql`
+      INSERT INTO ai_agent_roles (id, workspace_id, name, instructions, model_config)
+      VALUES (
+        ${id}, ${w1}, ${`Legacy-${id}`}, 'x',
+        to_jsonb(${'{"driver":"openai","chatModel":"gpt"}'}::text)
+      )
+    `.execute(db);
+    expect(await jsonbTypeof(id)).toBe('string'); // sanity: really corrupt
+
+    expect((await repo.findById(id, w1))?.modelConfig).toEqual({
+      driver: 'openai',
+      chatModel: 'gpt',
+    });
+  });
 });

apps/server/test/integration/ai-chat-message-status.int-spec.ts

@@ -0,0 +1,270 @@
+import { Kysely } from 'kysely';
+import { AiChatMessageRepo } from '@docmost/db/repos/ai-chat/ai-chat-message.repo';
+import {
+  getTestDb,
+  destroyTestDb,
+  createWorkspace,
+  createUser,
+  createChat,
+  createMessage,
+} from './db';
+
+/**
+ * Integration coverage for the #183 step-granular durability primitives on
+ * AiChatMessageRepo: `update` (in-place patch by id+workspace, bumps updatedAt,
+ * returns the row) and `sweepStreaming` (crash recovery: flip dangling
+ * 'streaming' rows to 'aborted'). Real SQL against docmost_test, not a mock.
+ */
+describe('AiChatMessageRepo.update + sweepStreaming [integration]', () => {
+  let db: Kysely<any>;
+  let repo: AiChatMessageRepo;
+  let workspaceId: string;
+  let otherWorkspaceId: string;
+  let userId: string;
+  let chatId: string;
+  let otherChatId: string;
+
+  beforeAll(async () => {
+    db = getTestDb();
+    repo = new AiChatMessageRepo(db as any);
+    workspaceId = (await createWorkspace(db)).id;
+    otherWorkspaceId = (await createWorkspace(db)).id;
+    userId = (await createUser(db, workspaceId)).id;
+    chatId = (await createChat(db, { workspaceId, creatorId: userId })).id;
+    const otherUser = await createUser(db, otherWorkspaceId);
+    otherChatId = (
+      await createChat(db, {
+        workspaceId: otherWorkspaceId,
+        creatorId: otherUser.id,
+      })
+    ).id;
+  });
+
+  afterAll(async () => {
+    await destroyTestDb();
+  });
+
+  it('update patches content/status/metadata and bumps updatedAt', async () => {
+    const seeded = await repo.insert({
+      chatId,
+      workspaceId,
+      userId,
+      role: 'assistant',
+      content: '',
+      status: 'streaming',
+      metadata: { parts: [] } as never,
+    });
+    const before = seeded.updatedAt;
+    // Ensure a measurable timestamp delta.
+    await new Promise((r) => setTimeout(r, 5));
+
+    const updated = await repo.update(seeded.id, workspaceId, {
+      content: 'final answer',
+      status: 'completed',
+      metadata: { parts: [{ type: 'text', text: 'final answer' }] },
+    });
+
+    expect(updated).toBeDefined();
+    expect(updated!.content).toBe('final answer');
+    expect(updated!.status).toBe('completed');
+    expect((updated!.metadata as any).parts).toHaveLength(1);
+    // The 5ms sleep above guarantees a strictly-later timestamp.
+    expect(new Date(updated!.updatedAt).getTime()).toBeGreaterThan(
+      new Date(before).getTime(),
+    );
+  });
+
+  it('onlyIfStreaming update is a NO-OP once the row is finalized (race guard)', async () => {
+    // Reproduce the step-update-vs-finalize race (#183 review): the row is
+    // finalized to 'completed', then a LATE per-step 'streaming' update lands.
+    // With `onlyIfStreaming` it must match nothing and leave the finalized row
+    // untouched (no clobber back to 'streaming', no lost usage).
+    const seeded = await repo.insert({
+      chatId,
+      workspaceId,
+      userId,
+      role: 'assistant',
+      content: 'partial',
+      status: 'streaming',
+    });
+    // Terminal finalize (unguarded) wins.
+    await repo.update(seeded.id, workspaceId, {
+      content: 'final answer',
+      status: 'completed',
+      metadata: { usage: { totalTokens: 42 } } as never,
+    });
+    // A straggler per-step update arrives AFTER finalize.
+    const late = await repo.update(
+      seeded.id,
+      workspaceId,
+      { content: 'partial', status: 'streaming', metadata: {} as never },
+      { onlyIfStreaming: true },
+    );
+    expect(late).toBeUndefined(); // matched no 'streaming' row -> no-op
+    const rows = await repo.findAllByChat(chatId, workspaceId);
+    const row = rows.find((r) => r.id === seeded.id)!;
+    expect(row.status).toBe('completed'); // NOT clobbered back to streaming
+    expect(row.content).toBe('final answer');
+    expect((row.metadata as any).usage.totalTokens).toBe(42); // usage preserved
+  });
+
+  it('update is workspace-scoped: a foreign workspace id matches nothing', async () => {
+    const seeded = await repo.insert({
+      chatId,
+      workspaceId,
+      userId,
+      role: 'assistant',
+      content: 'orig',
+      status: 'streaming',
+    });
+    const res = await repo.update(seeded.id, otherWorkspaceId, {
+      status: 'completed',
+    });
+    expect(res).toBeUndefined();
+    // The row in the real workspace is untouched.
+    const rows = await repo.findAllByChat(chatId, workspaceId);
+    const stillThere = rows.find((r) => r.id === seeded.id);
+    expect(stillThere!.status).toBe('streaming');
+    // Clean up so it does not pollute the sweep test below.
+    await repo.update(seeded.id, workspaceId, { status: 'completed' });
+  });
+
+  // Backdate a row's updatedAt so it qualifies as a STALE streaming row (the
+  // sweep only flips rows untouched for >10 minutes — a live turn bumps
+  // updatedAt every step, so it would never match).
+  async function backdateUpdatedAt(
+    id: string,
+    minutesAgo: number,
+  ): Promise<void> {
+    await db
+      .updateTable('aiChatMessages')
+      .set({ updatedAt: new Date(Date.now() - minutesAgo * 60 * 1000) })
+      .where('id', '=', id)
+      .execute();
+  }
+
+  it('sweepStreaming flips STALE dangling streaming rows to aborted and counts them', async () => {
+    // Two dangling streaming rows in our workspace + one in another workspace —
+    // all backdated past the staleness threshold so the sweep picks them up.
+    const a = await createMessage(db, {
+      workspaceId,
+      chatId,
+      role: 'assistant',
+      status: 'streaming',
+    });
+    const b = await createMessage(db, {
+      workspaceId,
+      chatId,
+      role: 'assistant',
+      status: 'streaming',
+    });
+    const other = await createMessage(db, {
+      workspaceId: otherWorkspaceId,
+      chatId: otherChatId,
+      role: 'assistant',
+      status: 'streaming',
+    });
+    await backdateUpdatedAt(a.id, 20);
+    await backdateUpdatedAt(b.id, 20);
+    await backdateUpdatedAt(other.id, 20);
+
+    // A settled row must NOT be touched.
+    const done = await createMessage(db, {
+      workspaceId,
+      chatId,
+      role: 'assistant',
+      status: 'completed',
+    });
+    // A legacy NULL-status row must NOT be touched.
+    const legacy = await createMessage(db, {
+      workspaceId,
+      chatId,
+      role: 'assistant',
+      status: null,
+    });
+
+    const swept = await repo.sweepStreaming();
+    // At least the 3 stale streaming rows we created (2 here + 1 in the other ws).
+    expect(swept).toBeGreaterThanOrEqual(3);
+
+    const rows = await repo.findAllByChat(chatId, workspaceId);
+    const byId = new Map(rows.map((r) => [r.id, r]));
+    expect(byId.get(a.id)!.status).toBe('aborted');
+    expect(byId.get(b.id)!.status).toBe('aborted');
+    expect(byId.get(done.id)!.status).toBe('completed');
+    expect(byId.get(legacy.id)!.status).toBeNull();
+
+    // Idempotent: a second sweep finds nothing left in our seeded set.
+    const again = await repo.sweepStreaming();
+    const rows2 = await repo.findAllByChat(chatId, workspaceId);
+    // Our two rows stay aborted regardless of `again`'s global count.
+    expect(rows2.find((r) => r.id === a.id)!.status).toBe('aborted');
+    expect(again).toBeGreaterThanOrEqual(0);
+  });
+
+  it('sweepStreaming does NOT sweep a FRESH streaming row (recency bound, #183 review)', async () => {
+    // A row that is actively streaming (recent updatedAt) must survive the sweep:
+    // a fresh replica's boot-sweep must never abort a turn another replica is
+    // still streaming in a multi-instance deploy.
+    const fresh = await createMessage(db, {
+      workspaceId,
+      chatId,
+      role: 'assistant',
+      status: 'streaming',
+    });
+    // A STALE streaming row created alongside it IS swept — proving the sweep
+    // ran and the only difference is recency.
+    const stale = await createMessage(db, {
+      workspaceId,
+      chatId,
+      role: 'assistant',
+      status: 'streaming',
+    });
+    await backdateUpdatedAt(stale.id, 20);
+
+    await repo.sweepStreaming();
+
+    const rows = await repo.findAllByChat(chatId, workspaceId);
+    const byId = new Map(rows.map((r) => [r.id, r]));
+    // Fresh (recently-updated) streaming row is left untouched...
+    expect(byId.get(fresh.id)!.status).toBe('streaming');
+    // ...while the stale one alongside it was swept to 'aborted'.
+    expect(byId.get(stale.id)!.status).toBe('aborted');
+  });
+
+  it('findAllByChat caps the result, keeping the NEWEST messages in order (#183 review)', async () => {
+    // A dedicated chat so the cap test is independent of the rows above.
+    const cappedChat = (
+      await createChat(db, { workspaceId, creatorId: userId })
+    ).id;
+    const base = Date.now();
+    // Three messages at strictly increasing timestamps.
+    await createMessage(db, {
+      workspaceId,
+      chatId: cappedChat,
+      content: 'm1-oldest',
+      createdAt: new Date(base),
+    });
+    await createMessage(db, {
+      workspaceId,
+      chatId: cappedChat,
+      content: 'm2',
+      createdAt: new Date(base + 1000),
+    });
+    await createMessage(db, {
+      workspaceId,
+      chatId: cappedChat,
+      content: 'm3-newest',
+      createdAt: new Date(base + 2000),
+    });
+
+    // Cap of 2 -> the OLDEST message is dropped; the newest two stay, in
+    // chronological order (oldest -> newest).
+    const capped = await repo.findAllByChat(cappedChat, workspaceId, 2);
+    expect(capped.map((r) => r.content)).toEqual(['m2', 'm3-newest']);
+
+    // Without a cap (well above the row count) all three come back in order.
+    const all = await repo.findAllByChat(cappedChat, workspaceId, 100);
+    expect(all.map((r) => r.content)).toEqual(['m1-oldest', 'm2', 'm3-newest']);
+  });
+});

apps/server/test/integration/ai-mcp-server-repo.int-spec.ts

@@ -0,0 +1,194 @@
+import { Kysely, sql } from 'kysely';
+import { randomUUID } from 'node:crypto';
+import { AiMcpServerRepo } from '@docmost/db/repos/ai-chat/ai-mcp-server.repo';
+import { getTestDb, destroyTestDb, createWorkspace } from './db';
+
+/**
+ * AiMcpServerRepo `tool_allowlist` jsonb round-trip (PR #172 / issue #173 §3).
+ *
+ * The fix under test is a DB round-trip, so a unit test cannot observe it: the
+ * write must land as a real jsonb ARRAY (not a double-encoded string scalar),
+ * and the read must repair any legacy string-scalar rows. The read-side
+ * `parseToolAllowlist` MASKS a write regression (it parses the string back), so
+ * without this integration check, reverting `::text::jsonb` to `::jsonb` would
+ * keep every unit test green while silently corrupting the column again.
+ */
+describe('AiMcpServerRepo tool_allowlist jsonb round-trip [integration]', () => {
+  let db: Kysely<any>;
+  let repo: AiMcpServerRepo;
+  let ws: string;
+
+  beforeAll(async () => {
+    db = getTestDb();
+    repo = new AiMcpServerRepo(db as any);
+    ws = (await createWorkspace(db)).id;
+  });
+
+  afterAll(async () => {
+    await destroyTestDb();
+  });
+
+  const jsonbTypeof = async (id: string): Promise<string | null> => {
+    const res = await sql<{ t: string | null }>`
+      SELECT jsonb_typeof(tool_allowlist) AS t
+      FROM ai_mcp_servers WHERE id = ${id}
+    `.execute(db);
+    return res.rows[0]?.t ?? null;
+  };
+
+  it('insert stores the allowlist as a jsonb ARRAY (not a string scalar)', async () => {
+    const row = await repo.insert({
+      workspaceId: ws,
+      name: `srv-${randomUUID()}`,
+      transport: 'http',
+      url: 'https://example.com/mcp',
+      toolAllowlist: ['search', 'crawl'],
+    });
+
+    // The column holds a real jsonb array — the whole point of ::text::jsonb.
+    expect(await jsonbTypeof(row.id)).toBe('array');
+
+    // And the read returns a genuine string[], not a JSON string.
+    const found = await repo.findById(row.id, ws);
+    expect(found?.toolAllowlist).toEqual(['search', 'crawl']);
+    expect(Array.isArray(found?.toolAllowlist)).toBe(true);
+  });
+
+  it('an empty allowlist is normalized to null (no restriction), not []', async () => {
+    const row = await repo.insert({
+      workspaceId: ws,
+      name: `srv-${randomUUID()}`,
+      transport: 'http',
+      url: 'https://example.com/mcp',
+      toolAllowlist: [],
+    });
+    // The column is SQL NULL, so jsonb_typeof returns SQL NULL (JS null).
+    expect(await jsonbTypeof(row.id)).toBeNull();
+    expect((await repo.findById(row.id, ws))?.toolAllowlist).toBeNull();
+  });
+
+  it('repairs a legacy double-encoded (string scalar) row on read (self-heal)', async () => {
+    // Seed a row whose tool_allowlist is a jsonb STRING SCALAR holding the JSON
+    // text — exactly what the old `::jsonb` double-encoding produced.
+    const id = randomUUID();
+    await sql`
+      INSERT INTO ai_mcp_servers (id, workspace_id, name, transport, url, tool_allowlist)
+      VALUES (
+        ${id}, ${ws}, ${`srv-${id}`}, 'http', 'https://example.com/mcp',
+        to_jsonb(${'["alpha","beta"]'}::text)
+      )
+    `.execute(db);
+
+    // Sanity: the seeded column really IS the corrupt string-scalar shape.
+    expect(await jsonbTypeof(id)).toBe('string');
+
+    // The repo read heals it back to a real string[].
+    expect((await repo.findById(id, ws))?.toolAllowlist).toEqual([
+      'alpha',
+      'beta',
+    ]);
+    const enabled = await repo.listEnabled(ws);
+    const healed = enabled.find((r) => r.id === id);
+    expect(healed?.toolAllowlist).toEqual(['alpha', 'beta']);
+  });
+
+  it('FAIL-OPEN: a present-but-corrupt tool_allowlist reads back as null (no restriction)', async () => {
+    // #185 re-review pt 8: normalizeRow's fail-open branch — the column is
+    // PRESENT but does not parse into a string[] (here a jsonb string scalar
+    // holding non-array JSON). The read must degrade to `null` ("no restriction"),
+    // not crash. (A warn is logged with the server id; not asserted here.)
+    const id = randomUUID();
+    await sql`
+      INSERT INTO ai_mcp_servers (id, workspace_id, name, transport, url, tool_allowlist)
+      VALUES (
+        ${id}, ${ws}, ${`srv-${id}`}, 'http', 'https://example.com/mcp',
+        to_jsonb(${'{"not":"an array"}'}::text)
+      )
+    `.execute(db);
+    // Sanity: the column is present (a jsonb string scalar), not SQL NULL.
+    expect(await jsonbTypeof(id)).toBe('string');
+    // ...yet the read degrades to null (fail-open).
+    expect((await repo.findById(id, ws))?.toolAllowlist).toBeNull();
+  });
+});
+
+/**
+ * AiMcpServerRepo `instructions` text round-trip (#180). The column is plain
+ * text (no jsonb); blank/whitespace is normalized to null on both insert and
+ * update so an empty guide is never persisted.
+ */
+describe('AiMcpServerRepo instructions round-trip [integration]', () => {
+  let db: Kysely<any>;
+  let repo: AiMcpServerRepo;
+  let ws: string;
+
+  beforeAll(async () => {
+    db = getTestDb();
+    repo = new AiMcpServerRepo(db as any);
+    ws = (await createWorkspace(db)).id;
+  });
+
+  afterAll(async () => {
+    await destroyTestDb();
+  });
+
+  it('insert stores trimmed non-blank instructions and reads them back', async () => {
+    const row = await repo.insert({
+      workspaceId: ws,
+      name: `srv-${randomUUID()}`,
+      transport: 'http',
+      url: 'https://example.com/mcp',
+      instructions: '  Use search for fresh facts.  ',
+    });
+    expect((await repo.findById(row.id, ws))?.instructions).toBe(
+      'Use search for fresh facts.',
+    );
+  });
+
+  it('insert normalizes blank/whitespace instructions to null', async () => {
+    const row = await repo.insert({
+      workspaceId: ws,
+      name: `srv-${randomUUID()}`,
+      transport: 'http',
+      url: 'https://example.com/mcp',
+      instructions: '   ',
+    });
+    expect((await repo.findById(row.id, ws))?.instructions).toBeNull();
+  });
+
+  it('insert with omitted instructions stores null', async () => {
+    const row = await repo.insert({
+      workspaceId: ws,
+      name: `srv-${randomUUID()}`,
+      transport: 'http',
+      url: 'https://example.com/mcp',
+    });
+    expect((await repo.findById(row.id, ws))?.instructions).toBeNull();
+  });
+
+  it('update sets, clears (blank => null), and leaves unchanged when absent', async () => {
+    const row = await repo.insert({
+      workspaceId: ws,
+      name: `srv-${randomUUID()}`,
+      transport: 'http',
+      url: 'https://example.com/mcp',
+      instructions: 'initial guide',
+    });
+
+    // Set a new value.
+    await repo.update(row.id, ws, { instructions: 'updated guide' });
+    expect((await repo.findById(row.id, ws))?.instructions).toBe(
+      'updated guide',
+    );
+
+    // Absent in the patch => unchanged.
+    await repo.update(row.id, ws, { name: 'renamed' });
+    expect((await repo.findById(row.id, ws))?.instructions).toBe(
+      'updated guide',
+    );
+
+    // Blank => cleared to null.
+    await repo.update(row.id, ws, { instructions: '   ' });
+    expect((await repo.findById(row.id, ws))?.instructions).toBeNull();
+  });
+});

apps/server/test/integration/db.ts

@@ -104,7 +104,8 @@ export async function createWorkspace(
       name: overrides.name ?? `ws-${suffix}`,
       // hostname is uniquely constrained; keep it unique per workspace.
       hostname: `host-${suffix}`,
-      settings: overrides.settings === undefined ? null : (overrides.settings as any),
+      settings:
+        overrides.settings === undefined ? null : (overrides.settings as any),
     })
     .returning(['id', 'settings'])
     .executeTakeFirstOrThrow();
@@ -226,3 +227,37 @@ export async function createChat(
     .executeTakeFirstOrThrow();
   return { id: row.id as string };
 }
+
+export async function createMessage(
+  db: Kysely<any>,
+  args: {
+    workspaceId: string;
+    chatId: string;
+    userId?: string | null;
+    role?: string;
+    content?: string | null;
+    status?: string | null;
+    metadata?: unknown;
+    // Explicit timestamp so a test can control message ORDER (the default DB
+    // now() can tie within a millisecond, and the v4 id is not time-ordered).
+    createdAt?: Date;
+  },
+): Promise<{ id: string }> {
+  const id = randomUUID();
+  const row = await db
+    .insertInto('aiChatMessages')
+    .values({
+      id,
+      workspaceId: args.workspaceId,
+      chatId: args.chatId,
+      userId: args.userId ?? null,
+      role: args.role ?? 'assistant',
+      content: args.content ?? null,
+      status: args.status ?? null,
+      metadata: (args.metadata ?? null) as any,
+      ...(args.createdAt ? { createdAt: args.createdAt } : {}),
+    })
+    .returning(['id'])
+    .executeTakeFirstOrThrow();
+  return { id: row.id as string };
+}

packages/editor-ext/src/lib/footnote/footnote-numbering.ts

@@ -1,14 +1,15 @@
-import { EditorState, Plugin, PluginKey } from "@tiptap/pm/state";
-import { Decoration, DecorationSet } from "@tiptap/pm/view";
-import { Node as ProseMirrorNode } from "@tiptap/pm/model";
+import { EditorState, Plugin, PluginKey } from '@tiptap/pm/state';
+import { Decoration, DecorationSet } from '@tiptap/pm/view';
+import { Node as ProseMirrorNode } from '@tiptap/pm/model';
 import {
   FOOTNOTE_DEFINITION_NAME,
   FOOTNOTE_REFERENCE_NAME,
   computeFootnoteNumbers,
-} from "./footnote-util";
+  computeFootnoteRefCounts,
+} from './footnote-util';
 
 export const footnoteNumberingPluginKey = new PluginKey<FootnoteNumberingState>(
-  "footnoteNumbering",
+  'footnoteNumbering',
 );
 
 /**
@@ -21,6 +22,9 @@ export const footnoteNumberingPluginKey = new PluginKey<FootnoteNumberingState>(
 interface FootnoteNumberingState {
   /** referenceId -> 1-based display number, for the current doc. */
   numbers: Map<string, number>;
+  /** referenceId -> number of reference occurrences (>= 1), for the definition's
+   *  multi-backlink UI (#168). */
+  refCounts: Map<string, number>;
   /** Decorations rendering those numbers (refs + definitions). */
   decorations: DecorationSet;
 }
@@ -46,6 +50,7 @@ function buildFootnoteNumberingState(
   doc: ProseMirrorNode,
 ): FootnoteNumberingState {
   const numbers = computeFootnoteNumbers(doc);
+  const refCounts = computeFootnoteRefCounts(doc);
   const decorations: Decoration[] = [];
 
   doc.descendants((node, pos) => {
@@ -54,7 +59,7 @@ function buildFootnoteNumberingState(
       if (num != null) {
         decorations.push(
           Decoration.node(pos, pos + node.nodeSize, {
-            "data-footnote-number": String(num),
+            'data-footnote-number': String(num),
             style: `--footnote-number: "${num}";`,
           }),
         );
@@ -65,7 +70,7 @@ function buildFootnoteNumberingState(
       if (num != null) {
         decorations.push(
           Decoration.node(pos, pos + node.nodeSize, {
-            "data-footnote-number": String(num),
+            'data-footnote-number': String(num),
             style: `--footnote-number: "${num}";`,
           }),
         );
@@ -73,7 +78,11 @@ function buildFootnoteNumberingState(
     }
   });
 
-  return { numbers, decorations: DecorationSet.create(doc, decorations) };
+  return {
+    numbers,
+    refCounts,
+    decorations: DecorationSet.create(doc, decorations),
+  };
 }
 
 /**
@@ -90,6 +99,16 @@ export function getFootnoteNumber(
   return footnoteNumberingPluginKey.getState(state)?.numbers.get(id);
 }
 
+/**
+ * Read the cached reference-occurrence count for `id` (how many `[^id]` links
+ * point at this definition). Drives the definition's multi-backlink UI (#168):
+ * `> 1` renders ↩ a b c …, each scrolling to its own occurrence. Returns 0 when
+ * the plugin is not installed or the id is unknown (caller treats as single).
+ */
+export function getFootnoteRefCount(state: EditorState, id: string): number {
+  return footnoteNumberingPluginKey.getState(state)?.refCounts.get(id) ?? 0;
+}
+
 /**
  * ProseMirror plugin that renders footnote numbers as decorations. It never
  * mutates the document (safe in read-only / share and in collaboration) — it

packages/editor-ext/src/lib/footnote/footnote-reference.ts

@@ -1,14 +1,14 @@
-import { mergeAttributes, Node } from "@tiptap/core";
-import { TextSelection, Transaction } from "@tiptap/pm/state";
-import { ReactNodeViewRenderer } from "@tiptap/react";
+import { mergeAttributes, Node } from '@tiptap/core';
+import { TextSelection, Transaction } from '@tiptap/pm/state';
+import { ReactNodeViewRenderer } from '@tiptap/react';
 import {
   FOOTNOTE_DEFINITION_NAME,
   FOOTNOTE_REFERENCE_NAME,
   FOOTNOTES_LIST_NAME,
   generateFootnoteId,
-} from "./footnote-util";
-import { footnoteNumberingPlugin } from "./footnote-numbering";
-import { footnoteSyncPlugin, footnotePastePlugin } from "./footnote-sync";
+} from './footnote-util';
+import { footnoteNumberingPlugin } from './footnote-numbering';
+import { footnoteSyncPlugin, footnotePastePlugin } from './footnote-sync';
 
 export interface FootnoteReferenceOptions {
   HTMLAttributes: Record<string, any>;
@@ -27,7 +27,7 @@ export interface FootnoteReferenceOptions {
   enableSync?: boolean;
 }
 
-declare module "@tiptap/core" {
+declare module '@tiptap/core' {
   interface Commands<ReturnType> {
     footnote: {
       /**
@@ -42,8 +42,11 @@ declare module "@tiptap/core" {
       removeFootnote: (id: string) => ReturnType;
       /** Scroll to (and focus) a footnote definition by id. */
       scrollToFootnote: (id: string) => ReturnType;
-      /** Scroll to (and select) a footnote reference by id. */
-      scrollToReference: (id: string) => ReturnType;
+      /** Scroll to a footnote reference by id. `index` selects WHICH occurrence
+       *  to scroll to when the id is referenced more than once (reuse, #166):
+       *  0-based, defaults to the first. Used by the definition's multi-backlink
+       *  UI (#168). */
+      scrollToReference: (id: string, index?: number) => ReturnType;
     };
   }
 }
@@ -66,7 +69,7 @@ export const FootnoteReference = Node.create<FootnoteReferenceOptions>({
   // Superscript mark's <sup> rule.
   priority: 101,
 
-  group: "inline",
+  group: 'inline',
   inline: true,
   atom: true,
   selectable: true,
@@ -99,10 +102,10 @@ export const FootnoteReference = Node.create<FootnoteReferenceOptions>({
     return {
       id: {
         default: null,
-        parseHTML: (element) => element.getAttribute("data-id"),
+        parseHTML: (element) => element.getAttribute('data-id'),
         renderHTML: (attributes) => {
           if (!attributes.id) return {};
-          return { "data-id": attributes.id };
+          return { 'data-id': attributes.id };
         },
       },
     };
@@ -113,7 +116,7 @@ export const FootnoteReference = Node.create<FootnoteReferenceOptions>({
       {
         // High priority so the Superscript mark (which also matches <sup>) does
         // not claim a footnote reference and drop it as empty content.
-        tag: "sup[data-footnote-ref]",
+        tag: 'sup[data-footnote-ref]',
         priority: 100,
       },
     ];
@@ -121,9 +124,9 @@ export const FootnoteReference = Node.create<FootnoteReferenceOptions>({
 
   renderHTML({ HTMLAttributes }) {
     return [
-      "sup",
+      'sup',
       mergeAttributes(
-        { "data-footnote-ref": "", class: "footnote-ref" },
+        { 'data-footnote-ref': '', class: 'footnote-ref' },
         this.options.HTMLAttributes,
         HTMLAttributes,
       ),
@@ -132,7 +135,7 @@ export const FootnoteReference = Node.create<FootnoteReferenceOptions>({
 
   // Plain-text representation (used by generateText / markdown text fallbacks).
   renderText({ node }) {
-    return `[^${node.attrs.id ?? ""}]`;
+    return `[^${node.attrs.id ?? ''}]`;
   },
 
   addNodeView() {
@@ -170,8 +173,10 @@ export const FootnoteReference = Node.create<FootnoteReferenceOptions>({
 
           // Make sure the parent accepts an inline atom here.
           const insertPos = selection.from;
-          if (!$from.parent.type.spec.content?.includes("inline") &&
-              !$from.parent.isTextblock) {
+          if (
+            !$from.parent.type.spec.content?.includes('inline') &&
+            !$from.parent.isTextblock
+          ) {
             return false;
           }
 
@@ -311,19 +316,23 @@ export const FootnoteReference = Node.create<FootnoteReferenceOptions>({
             `[data-footnote-def][data-id="${id}"]`,
           ) as HTMLElement | null;
           if (!dom) return false;
-          dom.scrollIntoView({ behavior: "smooth", block: "center" });
+          dom.scrollIntoView({ behavior: 'smooth', block: 'center' });
           return true;
         },
 
       scrollToReference:
-        (id: string) =>
+        (id: string, index = 0) =>
         ({ editor }) => {
           if (!id) return false;
-          const dom = editor.view.dom.querySelector(
+          // querySelectorAll returns the occurrences in document order, so the
+          // index maps 1:1 to the definition's a/b/c backlink (#168). Fall back
+          // to the first match for an out-of-range index.
+          const matches = editor.view.dom.querySelectorAll(
             `sup[data-footnote-ref][data-id="${id}"]`,
-          ) as HTMLElement | null;
+          );
+          const dom = (matches[index] ?? matches[0]) as HTMLElement | undefined;
           if (!dom) return false;
-          dom.scrollIntoView({ behavior: "smooth", block: "center" });
+          dom.scrollIntoView({ behavior: 'smooth', block: 'center' });
           return true;
         },
     };

packages/editor-ext/src/lib/footnote/footnote-util.ts

@@ -1,12 +1,12 @@
-import { Node as ProseMirrorNode } from "@tiptap/pm/model";
+import { Node as ProseMirrorNode } from '@tiptap/pm/model';
 
 /**
  * Node type names for the footnote feature. Centralized so every part of the
  * feature (nodes, plugins, commands) references the same string.
  */
-export const FOOTNOTE_REFERENCE_NAME = "footnoteReference";
-export const FOOTNOTES_LIST_NAME = "footnotesList";
-export const FOOTNOTE_DEFINITION_NAME = "footnoteDefinition";
+export const FOOTNOTE_REFERENCE_NAME = 'footnoteReference';
+export const FOOTNOTES_LIST_NAME = 'footnotesList';
+export const FOOTNOTE_DEFINITION_NAME = 'footnoteDefinition';
 
 /**
  * Generate a uuidv7-style id (time-ordered). Implemented locally so editor-ext
@@ -15,10 +15,10 @@ export const FOOTNOTE_DEFINITION_NAME = "footnoteDefinition";
  */
 export function generateFootnoteId(): string {
   const now = Date.now();
-  const timeHex = now.toString(16).padStart(12, "0");
+  const timeHex = now.toString(16).padStart(12, '0');
 
   const rand = (length: number) => {
-    let out = "";
+    let out = '';
     for (let i = 0; i < length; i++) {
       out += Math.floor(Math.random() * 16).toString(16);
     }
@@ -26,19 +26,19 @@ export function generateFootnoteId(): string {
   };
 
   // version 7 nibble, then variant (8..b) nibble.
-  const versioned = "7" + rand(3);
+  const versioned = '7' + rand(3);
   const variantNibble = (8 + Math.floor(Math.random() * 4)).toString(16);
   const variant = variantNibble + rand(3);
 
   return (
     timeHex.slice(0, 8) +
-    "-" +
+    '-' +
     timeHex.slice(8, 12) +
-    "-" +
+    '-' +
     versioned +
-    "-" +
+    '-' +
     variant +
-    "-" +
+    '-' +
     rand(12)
   );
 }
@@ -89,7 +89,7 @@ export function deriveFootnoteId(
  * Purely deterministic.
  */
 function suffix(n: number): string {
-  let out = "";
+  let out = '';
   let x = n;
   while (x > 0) {
     const rem = (x - 1) % 25;
@@ -131,3 +131,19 @@ export function computeFootnoteNumbers(
   }
   return numbers;
 }
+
+/**
+ * Build a map of `referenceId -> number of reference occurrences` (>= 1) from
+ * document order. After #166 the same id may be referenced multiple times
+ * (reuse: one number, one definition, N forward links); this count drives the
+ * definition's multi-backlink UI (↩ a b c …, #168). Pure function of the doc.
+ */
+export function computeFootnoteRefCounts(
+  doc: ProseMirrorNode,
+): Map<string, number> {
+  const counts = new Map<string, number>();
+  for (const id of collectReferenceIds(doc)) {
+    counts.set(id, (counts.get(id) ?? 0) + 1);
+  }
+  return counts;
+}

packages/git-sync/build/engine/client.types.d.ts

@@ -0,0 +1,109 @@
+/**
+ * The client seam. `pull.ts`/`push.ts` depend on a narrow STRUCTURAL interface
+ * rather than any concrete client, because the gitmost server writes NATIVELY —
+ * through repositories + collab `openDirectConnection`.
+ *
+ * `GitSyncClient` is that interface: the native datasource (server side)
+ * implements it, and the engine only ever uses `Pick<GitSyncClient, ...>`
+ * subsets of it. The signatures below MIRROR exactly the methods the engine's
+ * `pull.ts`/`push.ts` actually call (arg shapes + the fields the engine reads
+ * off each result), so a REST-style client is still structurally assignable and
+ * the native adapter has a precise contract.
+ */
+/**
+ * A page node as returned by `listSpaceTree` (the sidebar/tree walk, no body).
+ * The engine layout (`buildVaultLayout`) consumes `PageNode` from `./layout`,
+ * which only requires `id` (+ optional `title`/`slugId`/`parentPageId`); this
+ * lite shape documents the fields the tree walk surfaces. Real tree nodes also
+ * carry `position`, `icon`, `hasChildren` — kept open via the index signature.
+ */
+export interface GitSyncPageNodeLite {
+    id: string;
+    slugId?: string;
+    title?: string;
+    parentPageId?: string | null;
+    hasChildren?: boolean;
+    /** `listSpaceTree` nodes carry extra fields (position, icon, …). */
+    [key: string]: unknown;
+}
+/**
+ * The structural client the engine depends on. Only `Pick<GitSyncClient, ...>`
+ * subsets are ever used:
+ *   - pull reads:  `getPageJson` (+ the tree walk's `listSpaceTree`),
+ *   - push writes: `importPageMarkdown` / `createPage` / `deletePage` /
+ *                  `movePage` / `renamePage`,
+ *   - continuous (phase B+): `listRecentSince` / `listTrash` / `restorePage`.
+ */
+export interface GitSyncClient {
+    /**
+     * Full tree of page nodes for the space (or the subtree rooted at
+     * `rootPageId`), each WITHOUT body content. `complete` is `false` when the
+     * walk was truncated / a fetch failed — the pull side suppresses absence
+     * deletions on an incomplete tree (SPEC §8). Native impl returns
+     * `complete: true` always (reads the DB, not a paginated REST endpoint).
+     */
+    listSpaceTree(spaceId: string, rootPageId?: string): Promise<{
+        pages: GitSyncPageNodeLite[];
+        complete: boolean;
+    }>;
+    /**
+     * One page WITH its ProseMirror body content. `applyPullActions` reads
+     * `id`, `slugId`, `title`, `parentPageId`, `spaceId` (for the file meta) and
+     * `content` (to stabilize/serialize). `updatedAt` is carried for the
+     * poll-suppression loop-guard.
+     */
+    getPageJson(pageId: string): Promise<{
+        id: string;
+        slugId: string;
+        title: string;
+        parentPageId: string | null;
+        spaceId: string;
+        updatedAt: string;
+        content: unknown;
+    }>;
+    /**
+     * Merge a page's body from a self-contained markdown file (meta + body). The
+     * collab/Yjs write path (SPEC §2/§15.6) — never a raw jsonb overwrite.
+     * `applyPushActions` reads only an optional `updatedAt` off the result
+     * (via `extractUpdatedAt`, tolerant of extra fields).
+     *
+     * `baseMarkdown` is the last-synced version of the file (`refs/docmost/
+     * last-pushed`), the common ancestor for a THREE-WAY merge against the live
+     * doc so concurrent human edits survive (review #5). Optional/null -> 2-way.
+     */
+    importPageMarkdown(pageId: string, fullMarkdown: string, baseMarkdown?: string | null): Promise<{
+        updatedAt?: string;
+        [key: string]: unknown;
+    }>;
+    /**
+     * Create a new page and return the assigned id at `data.id`
+     * (`applyPushActions` reads `result.data.id`, then writes it back into the
+     * file's meta). An optional top-level/`data.updatedAt` feeds the loop-guard.
+     */
+    createPage(title: string, content: string, spaceId: string, parentPageId?: string): Promise<{
+        data: {
+            id: string;
+        };
+        updatedAt?: string;
+        [key: string]: unknown;
+    }>;
+    /** Soft-delete a page to Trash (SPEC §8). Result is not inspected. */
+    deletePage(pageId: string): Promise<unknown>;
+    /**
+     * Reparent a page (and optionally set its fractional-index `position`). The
+     * engine passes `position` UNDEFINED for now; the native impl computes a
+     * default between siblings. Result is not inspected.
+     */
+    movePage(pageId: string, parentPageId: string | null, position?: string): Promise<unknown>;
+    /** Change a page's title only (no body touch). Result is not inspected. */
+    renamePage(pageId: string, title: string): Promise<unknown>;
+    /**
+     * Pages updated since `sinceIso` (the poll-safety reconciliation, SPEC §8).
+     * `spaceId` may be undefined (all spaces); `hardPageCap` bounds the walk.
+     */
+    listRecentSince(spaceId: string | undefined, sinceIso: string | null, hardPageCap?: number): Promise<unknown[]>;
+    /** List soft-deleted (trashed) pages for the space (deletion detection). */
+    listTrash(spaceId: string): Promise<unknown[]>;
+    /** Restore a soft-deleted page from Trash. Result is not inspected. */
+    restorePage(pageId: string): Promise<unknown>;
+}

packages/git-sync/build/engine/client.types.js

@@ -0,0 +1,13 @@
+/**
+ * The client seam. `pull.ts`/`push.ts` depend on a narrow STRUCTURAL interface
+ * rather than any concrete client, because the gitmost server writes NATIVELY —
+ * through repositories + collab `openDirectConnection`.
+ *
+ * `GitSyncClient` is that interface: the native datasource (server side)
+ * implements it, and the engine only ever uses `Pick<GitSyncClient, ...>`
+ * subsets of it. The signatures below MIRROR exactly the methods the engine's
+ * `pull.ts`/`push.ts` actually call (arg shapes + the fields the engine reads
+ * off each result), so a REST-style client is still structurally assignable and
+ * the native adapter has a precise contract.
+ */
+export {};

packages/git-sync/build/engine/config-errors.d.ts

@@ -0,0 +1 @@
+export declare function loadSettingsOrExit<T>(factory: () => T): T;

packages/git-sync/build/engine/config-errors.js

@@ -0,0 +1,50 @@
+import { ZodError } from 'zod';
+// Turn a ZodError from settings validation into a clear, actionable startup
+// message that names the offending env var(s), then exit(1) — no raw stack
+// trace. Mirrors the Python new-project skeleton's load_settings_or_exit.
+// A non-ZodError is left to propagate unchanged.
+export function loadSettingsOrExit(factory) {
+    try {
+        return factory();
+    }
+    catch (err) {
+        if (!(err instanceof ZodError))
+            throw err;
+        const missing = [];
+        const invalid = [];
+        for (const issue of err.issues) {
+            const name = issue.path.length ? String(issue.path[0]) : '?';
+            // A missing required variable surfaces as an `invalid_type` issue whose
+            // received value was `undefined`. zod 3 exposed `issue.received` directly;
+            // zod 4 dropped that field and instead folds it into the message
+            // ("expected string, received undefined"). Detect both shapes so the
+            // missing-vs-invalid split holds across zod majors. NOTE: an invalid (but
+            // present) value uses a different code (invalid_format / invalid_value) or
+            // an `invalid_type` message that reports a non-undefined received (e.g.
+            // "received NaN" from a coerced number), so neither is misread as missing.
+            const i = issue;
+            const isMissing = issue.code === 'invalid_type' &&
+                (i.received === 'undefined' ||
+                    /received undefined/i.test(i.message ?? ''));
+            if (isMissing)
+                missing.push(name);
+            else
+                invalid.push(`${name}: ${issue.message}`);
+        }
+        const lines = ['Configuration error in environment / .env:'];
+        if (missing.length) {
+            lines.push('  Missing required variable(s):');
+            for (const n of [...new Set(missing)])
+                lines.push(`    - ${n}`);
+        }
+        if (invalid.length) {
+            lines.push('  Invalid value(s):');
+            for (const item of invalid)
+                lines.push(`    - ${item}`);
+        }
+        lines.push('');
+        lines.push('Set them in .env (see .env.example) and try again.');
+        process.stderr.write(lines.join('\n') + '\n');
+        process.exit(1);
+    }
+}

packages/git-sync/build/engine/cycle.d.ts

@@ -0,0 +1,70 @@
+import { VaultGit } from "./git.js";
+import { GitSyncClient } from "./client.types.js";
+import { Settings } from "./settings.js";
+/**
+ * Absolute-path filesystem primitives the cycle needs. Injected (not imported)
+ * so the engine stays IO-free and unit-testable. `mkdir` is recursive; `rm` is
+ * force (a missing file is a no-op).
+ */
+export interface CycleFs {
+    readFile: (absPath: string) => Promise<string>;
+    writeFile: (absPath: string, text: string) => Promise<void>;
+    mkdir: (absDir: string) => Promise<void>;
+    rm: (absPath: string) => Promise<void>;
+}
+export interface RunCycleDeps {
+    spaceId: string;
+    /** The Docmost seam (reads for pull, writes for push). */
+    client: GitSyncClient;
+    /** The per-space git vault (a real working repo). */
+    vault: VaultGit;
+    /** Engine settings; `vaultPath` roots the relPath -> absolute-path mapping. */
+    settings: Settings;
+    fs: CycleFs;
+    log: (line: string) => void;
+    /**
+     * Delete-cap hook (the ONLY caller-specific policy). Called with the push
+     * dry-run's planned delete count (`Number.POSITIVE_INFINITY` when the dry-run
+     * itself failed, so the hook can fail safe) and the live client; returns the
+     * client to use for the REAL apply. The default (omitted) applies every op
+     * unmodified. gitmost uses it to neutralize deletes when over its cap.
+     *
+     * When omitted, NO dry-run is performed (one fewer push planning pass).
+     */
+    resolveApplyClient?: (plannedDeletes: number, client: GitSyncClient) => GitSyncClient;
+}
+export interface RunCycleResult {
+    ran: boolean;
+    /** Set when the cycle short-circuited without running pull/push. */
+    skipped?: "merge-in-progress";
+    pull?: {
+        written: number;
+        deleted: number;
+        conflict: boolean;
+    };
+    push?: {
+        mode: string;
+        failures: number;
+    };
+}
+/**
+ * Run ONE full reconcile cycle for a space: PULL (Docmost -> vault) then PUSH
+ * (vault -> Docmost), under the engine's required branch choreography. This is
+ * the single entry point the app drives — it owns the staging order so it can
+ * never drift from the engine it ships with.
+ *
+ * Staging (the ⭐ data-loss-critical order, SPEC §6/§9):
+ *   1. assertGitAvailable + ensureRepo (the git state store must exist).
+ *   2. refuse on an unresolved merge (a prior conflicting pull); next checkout
+ *      would fail otherwise.
+ *   3. ensureBranch('docmost','main') + checkout('docmost'). Pull writes MUST
+ *      land on `docmost`, not `main`: applyPullActions commits on `docmost`,
+ *      then checks out `main` and merges docmost -> main. Writing Docmost
+ *      content straight onto `main` would clobber local file edits before push
+ *      can diff them.
+ *   4. PULL: readExisting -> listSpaceTree -> computePullActions -> apply.
+ *   5. PUSH: optional dry-run to feed the delete-cap hook, then the real apply.
+ *
+ * Lock + cap POLICY live in the caller; this owns only the mechanics.
+ */
+export declare function runCycle(deps: RunCycleDeps): Promise<RunCycleResult>;

packages/git-sync/build/engine/cycle.js

@@ -0,0 +1,97 @@
+import { readExisting, computePullActions, applyPullActions } from "./pull.js";
+import { runPush } from "./push.js";
+/**
+ * Run ONE full reconcile cycle for a space: PULL (Docmost -> vault) then PUSH
+ * (vault -> Docmost), under the engine's required branch choreography. This is
+ * the single entry point the app drives — it owns the staging order so it can
+ * never drift from the engine it ships with.
+ *
+ * Staging (the ⭐ data-loss-critical order, SPEC §6/§9):
+ *   1. assertGitAvailable + ensureRepo (the git state store must exist).
+ *   2. refuse on an unresolved merge (a prior conflicting pull); next checkout
+ *      would fail otherwise.
+ *   3. ensureBranch('docmost','main') + checkout('docmost'). Pull writes MUST
+ *      land on `docmost`, not `main`: applyPullActions commits on `docmost`,
+ *      then checks out `main` and merges docmost -> main. Writing Docmost
+ *      content straight onto `main` would clobber local file edits before push
+ *      can diff them.
+ *   4. PULL: readExisting -> listSpaceTree -> computePullActions -> apply.
+ *   5. PUSH: optional dry-run to feed the delete-cap hook, then the real apply.
+ *
+ * Lock + cap POLICY live in the caller; this owns only the mechanics.
+ */
+export async function runCycle(deps) {
+    const { spaceId, client, vault, settings, fs, log, resolveApplyClient } = deps;
+    const vaultRoot = settings.vaultPath;
+    const abs = (relPath) => `${vaultRoot}/${relPath}`;
+    // 1. The engine state store is git: make sure the repo + branches exist
+    //    before any tracked-file listing or diff.
+    await vault.assertGitAvailable();
+    await vault.ensureRepo();
+    // 2. Refuse to run on top of an unresolved merge (SPEC §9): a prior
+    //    conflicting pull leaves the vault mid-merge; the next checkout would fail.
+    if (await vault.isMergeInProgress()) {
+        log(`vault has an unresolved merge — resolve it (or 'git merge --abort') ` +
+            `and re-run (SPEC §9); skipping cycle.`);
+        return { ran: false, skipped: "merge-in-progress" };
+    }
+    // 3. Pull writes happen on `docmost`; be on it BEFORE applying (see docstring).
+    await vault.ensureBranch("docmost", "main");
+    await vault.checkout("docmost");
+    // 4. PULL --------------------------------------------------------------------
+    const existing = await readExisting({
+        listTracked: () => vault.listTrackedFiles("*.md"),
+        readFile: (relPath) => fs.readFile(abs(relPath)),
+    });
+    const tree = await client.listSpaceTree(spaceId);
+    const pullActions = computePullActions({
+        pages: tree.pages,
+        treeComplete: tree.complete,
+        existing,
+    });
+    const pullResult = await applyPullActions({
+        client,
+        git: vault,
+        writeFile: (absPath, text) => fs.writeFile(absPath, text),
+        mkdir: (absDir) => fs.mkdir(absDir),
+        rm: (absPath) => fs.rm(absPath),
+    }, pullActions, vaultRoot);
+    // 5. PUSH --------------------------------------------------------------------
+    const pushDeps = {
+        settings,
+        git: vault,
+        makeClient: () => client,
+        readFile: (relPath) => fs.readFile(abs(relPath)),
+        writeFile: (relPath, text) => fs.writeFile(abs(relPath), text),
+        log,
+    };
+    let applyClient = client;
+    if (resolveApplyClient) {
+        // Plan the push as a DRY-RUN first to read the delete count, then let the
+        // caller decide the apply client (e.g. neutralize deletes over a cap). A
+        // failed dry-run yields Infinity so the hook can fail safe.
+        let plannedDeletes;
+        try {
+            const dry = await runPush(pushDeps, { dryRun: true });
+            plannedDeletes = dry.planned?.deletes ?? 0;
+        }
+        catch (err) {
+            log(`push dry-run planning failed (${err instanceof Error ? err.message : String(err)}); deferring deletion policy to the cap hook (fail-safe).`);
+            plannedDeletes = Number.POSITIVE_INFINITY;
+        }
+        applyClient = resolveApplyClient(plannedDeletes, client);
+    }
+    const pushResult = await runPush({ ...pushDeps, makeClient: () => applyClient }, { dryRun: false });
+    return {
+        ran: true,
+        pull: {
+            written: pullResult.written,
+            deleted: pullResult.deleted,
+            conflict: pullResult.merge.conflict,
+        },
+        push: {
+            mode: pushResult.mode,
+            failures: pushResult.failures?.length ?? 0,
+        },
+    };
+}

packages/git-sync/build/engine/git.d.ts

@@ -0,0 +1,259 @@
+/** Bot identity used for engine-authored vault commits (SPEC §7.3). */
+export declare const BOT_AUTHOR_NAME = "Docmost Sync";
+export declare const BOT_AUTHOR_EMAIL = "docmost-sync@local";
+/** Default branch the vault repo is initialized on. */
+export declare const DEFAULT_BRANCH = "main";
+/**
+ * One row of `git diff --name-status` (SPEC §6 "ФС → Docmost"). `status` is the
+ * single-letter change code (`-M` rename detection on), `path` is the (new) file
+ * path; for a rename/copy (`R`/`C`) `oldPath` is the source and `path` is the
+ * destination, with `score` carrying git's similarity index (0–100).
+ */
+export interface DiffEntry {
+    status: "A" | "M" | "D" | "R" | "C";
+    /** New (destination) path. For A/M/D it is the only path. */
+    path: string;
+    /** Source path — present only for R/C. */
+    oldPath?: string;
+    /** Rename/copy similarity score (0–100) — present only for R/C. */
+    score?: number;
+}
+/** Result of a `merge`: whether it succeeded cleanly or left conflict markers. */
+export interface MergeResult {
+    /** True when the merge applied cleanly (fast-forward or clean 3-way). */
+    ok: boolean;
+    /** True when the merge stopped on conflicts (markers left in the worktree). */
+    conflict: boolean;
+    /** Raw combined stdout+stderr, for logging/diagnostics. */
+    output: string;
+}
+/** Options for an engine-authored commit (provenance, SPEC §7.3). */
+export interface CommitOptions {
+    authorName: string;
+    authorEmail: string;
+    /**
+     * Trailer lines appended to the commit message body (e.g.
+     * `Docmost-Sync-Source: docmost`). These are the machine-readable provenance
+     * the loop-guard keys on (SPEC §12, "commit-attribution").
+     */
+    trailers?: string[];
+}
+/**
+ * A git wrapper bound to a single vault path. Construct once per vault; every
+ * method runs git with `cwd = vaultPath`.
+ */
+export declare class VaultGit {
+    private readonly vaultPath;
+    constructor(vaultPath: string);
+    /**
+     * Preflight: verify a runnable `git` binary is on PATH. The daemon shells out
+     * to system `git` for every vault operation, so a missing binary (e.g. a slim
+     * container image without git) must fail fast with an actionable message
+     * rather than a cryptic ENOENT deep inside the first real git call. Presence
+     * check only — we do NOT gate on a specific version. Runs `git --version`
+     * with NO `cwd` (the vault dir may not exist yet at preflight time).
+     */
+    assertGitAvailable(): Promise<void>;
+    /**
+     * Run a git command in the vault and return trimmed stdout. THIN wrapper over
+     * the single `runRaw` primitive: throws a clear, unified Error (including
+     * stderr/stdout) on a non-zero exit.
+     */
+    private run;
+    /**
+     * The ONE primitive every git invocation in this module flows through. Builds
+     * the full argv (`--no-pager -c core.quotepath=false <args>`), env, cwd, and
+     * maxBuffer, runs git, and NEVER throws — it returns the exit info so callers
+     * can treat a non-zero exit as either an error (`run`) or a meaningful state
+     * (e.g. a merge conflict, a porcelain diff that "fails" deliberately).
+     *
+     *   - argv: ALWAYS prepends `--no-pager -c core.quotepath=false`, so git never
+     *     blocks on a pager and always prints verbatim UTF-8 paths (no octal
+     *     escaping/quoting). `quotepath=false` is the baseline for ALL path-
+     *     printing commands (ls-files, diff --name-only, …).
+     *   - cwd: `opts.cwd === null` -> do NOT set cwd (the preflight, where the
+     *     vault dir may not exist); otherwise `opts.cwd ?? this.vaultPath`.
+     *   - env: `vaultGitEnv(opts?.env)` (cwd-isolation + caller extras).
+     *   - On a spawn/exec error we capture the error `message` too, so a failure
+     *     before git could write to stderr (e.g. ENOENT) is NOT lost.
+     */
+    private runRaw;
+    /**
+     * Ensure the vault directory exists and is an initialized git repo on `main`
+     * with an initial (empty) commit so branches exist. Idempotent: safe to call
+     * on every run. Sets a LOCAL bot identity for the vault repo if none is set
+     * (so engine commits never fall back to a global/unset identity).
+     */
+    ensureRepo(): Promise<void>;
+    /** True if `cwd` is inside a git work-tree (the vault is initialized). */
+    private isRepo;
+    /** True if a LOCAL git config key is set in the vault repo. */
+    private hasLocalConfig;
+    /** True if the repo has at least one commit (HEAD resolves). */
+    private hasAnyCommit;
+    /** True if a branch with the given name exists. */
+    branchExists(name: string): Promise<boolean>;
+    /**
+     * Create `name` from `fromBranch` if it does not already exist. No-op (and no
+     * checkout) when the branch is already present.
+     */
+    ensureBranch(name: string, fromBranch: string): Promise<void>;
+    /** Name of the currently checked-out branch. */
+    currentBranch(): Promise<string>;
+    /** Check out an existing branch. */
+    checkout(name: string): Promise<void>;
+    /** Stage everything (adds, modifications, deletions). */
+    stageAll(): Promise<void>;
+    /**
+     * True if the vault is mid-merge (an unresolved merge from a previous run,
+     * SPEC §9 / §12). Detected via a `MERGE_HEAD` ref OR any unmerged
+     * (conflicted) index entries (`git ls-files -u`). The pull cycle checks this
+     * BEFORE any checkout so a left-over merge produces a clear, actionable
+     * message instead of a raw "you need to resolve your current index first"
+     * failure deep inside `checkout`. This is what makes re-runs converge
+     * (resumability, SPEC §12).
+     */
+    isMergeInProgress(): Promise<boolean>;
+    /**
+     * Commit the currently STAGED changes with an explicit author/committer
+     * identity and the given trailers appended to the message body (SPEC §7.3
+     * provenance). Returns `true` if a commit was made, `false` if there was
+     * nothing to commit (graceful no-op). The caller is expected to have staged
+     * its changes first (e.g. via `stageAll`).
+     */
+    commit(message: string, opts: CommitOptions): Promise<boolean>;
+    /**
+     * Low-level commit used by both `commit` and `ensureRepo`'s initial commit.
+     * Builds the full message with appended trailers and sets author + committer
+     * identity via env vars (so the committer matches the author, not the repo
+     * default).
+     */
+    private commitRaw;
+    /**
+     * Merge `fromBranch` into the current branch (`git merge --no-edit`).
+     * Fast-forwards when possible; performs a real 3-way merge otherwise. Conflict
+     * state is SURFACED (returned), NOT auto-resolved (SPEC §9): the conflict
+     * markers are left in the worktree for manual resolution by a later increment,
+     * and — critically — nothing is pushed to Docmost (we never write to Docmost
+     * anyway).
+     */
+    merge(fromBranch: string): Promise<MergeResult>;
+    /** True if the index has any unmerged (conflicted) paths. */
+    private hasUnmergedPaths;
+    /**
+     * List tracked files on the current branch (paths relative to the vault
+     * root, forward-slash separated). An optional glob (a git pathspec) narrows
+     * the listing, e.g. `"*.md"`.
+     *
+     * The target wiki is RUSSIAN, so vault file names routinely contain Cyrillic
+     * (e.g. `Колонка.md`). With git's DEFAULT `core.quotepath=true`, `ls-files`
+     * returns non-ASCII paths octal-escaped and double-quoted (`"\320\232..."`),
+     * which `src/pull.ts` `readExisting` would then parse as garbage paths,
+     * breaking move/duplicate detection. We defeat that two ways at once:
+     *   - `core.quotepath=false` disables the octal-escape/quoting. It is now the
+     *     `runRaw` argv baseline (prepended to EVERY invocation), so we no longer
+     *     pass it inline here.
+     *   - `-z` emits NUL-delimited RAW UTF-8 paths (no quoting, no newline
+     *     ambiguity), which we split on `\0`.
+     * We read the RAW stdout (NOT the trimming `run()` helper, which would mangle
+     * the NUL-delimited bytes) and split on `\0`, dropping empty entries. Paths
+     * are returned verbatim — git already emits forward slashes.
+     */
+    listTrackedFiles(glob?: string): Promise<string[]>;
+    /**
+     * Diff two refs with `--name-status -M -z` and parse the NUL-delimited output
+     * (SPEC §6: the FS→Docmost push direction diffs `main` against
+     * `refs/docmost/last-pushed`). Rename detection is ON (`-M`), so a moved/renamed
+     * file is reported as a single `R` row with both its old and new path instead
+     * of a delete+add pair — that distinction is what lets the push planner tell a
+     * move from a delete+create (SPEC §8 "Move vs delete").
+     *
+     * `-z` makes git emit NUL-delimited RAW UTF-8 records (the Russian wiki has
+     * Cyrillic file names) with NO quoting/escaping. The record shape differs by
+     * status:
+     *   - A/M/D:  `status\0path\0`
+     *   - R/C:    `Rnnn\0oldPath\0newPath\0`  (nnn = similarity score, e.g. `R100`)
+     * We read the RAW stdout (not the trimming `run()` helper, which would mangle
+     * the NUL bytes), split on `\0`, drop the trailing empty entry, and walk the
+     * tokens pulling 1 or 2 path tokens per status. Paths are returned verbatim.
+     */
+    diffNameStatus(fromRef: string, toRef: string): Promise<DiffEntry[]>;
+    /**
+     * Resolve a ref/commit-ish to its full SHA, or `null` if it does not exist.
+     * `rev-parse --verify --quiet` exits non-zero (and prints nothing) for an
+     * unknown ref, so a non-zero exit maps cleanly to `null`. Used to read
+     * `refs/docmost/last-pushed` (SPEC §5) — which is absent before the first push.
+     */
+    revParse(ref: string): Promise<string | null>;
+    /**
+     * Read a ref to its SHA, or `null` if unset. Thin alias over `revParse`,
+     * named for the push direction's marker `refs/docmost/last-pushed` (SPEC §5:
+     * "что из `main` уже отражено в Docmost").
+     */
+    readRef(ref: string): Promise<string | null>;
+    /**
+     * Point `ref` at `target` (`git update-ref <ref> <target>`). Used to advance
+     * `refs/docmost/last-pushed` to the just-pushed `main` commit after a push
+     * (SPEC §6 step 3 / §5). `target` may be a SHA or any commit-ish git accepts.
+     */
+    updateRef(ref: string, target: string): Promise<void>;
+    /**
+     * Fast-forward `branch` to `toCommit` — but ONLY if it is a TRUE fast-forward,
+     * i.e. the current `branch` tip is an ancestor of `toCommit` (verified via
+     * `git merge-base --is-ancestor <branch> <toCommit>`). Used to advance the
+     * `docmost` mirror branch after a clean push (SPEC §6 step 3 / §10): once a
+     * push succeeds, Docmost already contains the pushed `main` content, so the
+     * mirror must reflect it — otherwise the NEXT pull would diff our own write
+     * back and re-pull it (loop-guard).
+     *
+     * SAFETY — never force, never clobber divergent history:
+     *   - If `branch` IS an ancestor of `toCommit`, advance it with
+     *     `git update-ref refs/heads/<branch> <toCommit>`. The `docmost` branch is
+     *     NOT checked out during a push (push works on `main`), so updating the ref
+     *     directly is safe and avoids any working-tree touch.
+     *   - If `branch` is NOT an ancestor (divergent / would-be non-fast-forward),
+     *     do NOT move it — return `{ ok: false, reason: 'not-fast-forward' }` and
+     *     let the caller log it. We must never overwrite a `docmost` history that
+     *     has commits the push base does not contain.
+     *
+     * Returns `{ ok: true }` when the branch was advanced (or already at
+     * `toCommit`, a degenerate fast-forward), `{ ok: false, reason }` otherwise.
+     * A missing `branch` or `toCommit` also yields `{ ok: false }` with a reason.
+     */
+    fastForwardBranch(branch: string, toCommit: string): Promise<{
+        ok: boolean;
+        reason?: string;
+    }>;
+    /**
+     * Read a file's content at a specific ref (`git show <ref>:<path>`), or `null`
+     * if the path does not exist there. Used by the push direction to read the
+     * PRE-IMAGE of a DELETED file (e.g. at `refs/docmost/last-pushed`) so its
+     * `docmost:meta` — and therefore its `pageId` — can be recovered to translate
+     * the deletion into a `delete_page` (SPEC §6/§8: only TRACKED files, i.e. ones
+     * that had a pageId, are deleted in Docmost). A non-zero exit (path absent at
+     * that ref) maps to `null` rather than throwing.
+     */
+    showFileAtRef(ref: string, path: string): Promise<string | null>;
+}
+/**
+ * Build the environment for a vault git invocation (SPEC §12 cwd-isolation).
+ * Used by the single `runRaw` primitive every git command flows through, so
+ * these pins apply uniformly (including the `git --version` preflight).
+ *
+ * cwd-isolation is this module's central safety guarantee: every git command
+ * MUST operate on the vault repo at `cwd: vaultPath` and nothing else. An
+ * inherited `GIT_DIR` / `GIT_WORK_TREE` in `process.env` would silently
+ * redirect the operation away from `cwd` (e.g. to the source repo or another
+ * checkout), defeating that guarantee. So we always strip them, regardless of
+ * whatever else the caller adds (author/committer identity, etc.).
+ *
+ * Exported for unit testing.
+ */
+export declare function vaultGitEnv(extra?: Record<string, string>): NodeJS.ProcessEnv;
+/**
+ * Build a commit message body with trailer lines appended (SPEC §7.3). The
+ * trailers are separated from the subject by a blank line so `git interpret-
+ * trailers` / `git log --format=%(trailers)` parse them as trailers.
+ * Exported for unit testing.
+ */
+export declare function buildCommitMessage(subject: string, trailers?: string[]): string;

packages/git-sync/build/engine/git.js

@@ -0,0 +1,570 @@
+/**
+ * Thin async wrapper over the system `git` binary (SPEC §5: state store = git).
+ *
+ * IMPORTANT — VAULT-SCOPED: every operation here runs with `cwd = vaultPath`,
+ * which is the vault's OWN git repository (default `data/vault`), SEPARATE from
+ * the gitmost application repo. This module MUST NEVER run git against the
+ * application repo. `data/` is gitignored, so a nested repo under `data/vault`
+ * is safe. The pull cycle is READ-ONLY toward Docmost; this module only touches
+ * the local vault git, never a git remote (push is deferred, see SPEC §7).
+ *
+ * Implementation notes:
+ *   - We shell out via `node:child_process` `execFile` (promisified), passing
+ *     ARGS AS AN ARRAY — no shell, so there is no command injection surface even
+ *     if a page title / branch name contains shell metacharacters.
+ *   - EVERY git invocation funnels through the single `runRaw` primitive, which
+ *     ALWAYS prepends `--no-pager -c core.quotepath=false` to the argv (so git
+ *     never blocks on a pager and always prints verbatim UTF-8 paths). There is
+ *     no exception — even the `git --version` preflight goes through `runRaw`.
+ *   - "nothing to commit" is treated as a graceful no-op, not an error.
+ */
+import { execFile } from "node:child_process";
+import { mkdir } from "node:fs/promises";
+import { promisify } from "node:util";
+const execFileAsync = promisify(execFile);
+/** Bot identity used for engine-authored vault commits (SPEC §7.3). */
+export const BOT_AUTHOR_NAME = "Docmost Sync";
+export const BOT_AUTHOR_EMAIL = "docmost-sync@local";
+/** Default branch the vault repo is initialized on. */
+export const DEFAULT_BRANCH = "main";
+/**
+ * A git wrapper bound to a single vault path. Construct once per vault; every
+ * method runs git with `cwd = vaultPath`.
+ */
+export class VaultGit {
+    vaultPath;
+    constructor(vaultPath) {
+        this.vaultPath = vaultPath;
+    }
+    /**
+     * Preflight: verify a runnable `git` binary is on PATH. The daemon shells out
+     * to system `git` for every vault operation, so a missing binary (e.g. a slim
+     * container image without git) must fail fast with an actionable message
+     * rather than a cryptic ENOENT deep inside the first real git call. Presence
+     * check only — we do NOT gate on a specific version. Runs `git --version`
+     * with NO `cwd` (the vault dir may not exist yet at preflight time).
+     */
+    async assertGitAvailable() {
+        // Goes through the single `runRaw` primitive like every other invocation.
+        // `cwd: null` means "do not set a cwd" — the vault dir may not exist yet at
+        // preflight time, so we must not point git at a missing directory.
+        const r = await this.runRaw(["--version"], { cwd: null });
+        if (r.code !== 0) {
+            const detail = (r.stderr || r.stdout || "").trim();
+            throw new Error("git binary not found or not runnable — install git (the vault state " +
+                `store requires it). Underlying error: ${detail}`);
+        }
+    }
+    /**
+     * Run a git command in the vault and return trimmed stdout. THIN wrapper over
+     * the single `runRaw` primitive: throws a clear, unified Error (including
+     * stderr/stdout) on a non-zero exit.
+     */
+    async run(args, opts) {
+        const r = await this.runRaw(args, opts);
+        if (r.code !== 0) {
+            const detail = (r.stderr || r.stdout || "").trim();
+            throw new Error(`git ${args.join(" ")} failed: ${detail}`);
+        }
+        return r.stdout.trim();
+    }
+    /**
+     * The ONE primitive every git invocation in this module flows through. Builds
+     * the full argv (`--no-pager -c core.quotepath=false <args>`), env, cwd, and
+     * maxBuffer, runs git, and NEVER throws — it returns the exit info so callers
+     * can treat a non-zero exit as either an error (`run`) or a meaningful state
+     * (e.g. a merge conflict, a porcelain diff that "fails" deliberately).
+     *
+     *   - argv: ALWAYS prepends `--no-pager -c core.quotepath=false`, so git never
+     *     blocks on a pager and always prints verbatim UTF-8 paths (no octal
+     *     escaping/quoting). `quotepath=false` is the baseline for ALL path-
+     *     printing commands (ls-files, diff --name-only, …).
+     *   - cwd: `opts.cwd === null` -> do NOT set cwd (the preflight, where the
+     *     vault dir may not exist); otherwise `opts.cwd ?? this.vaultPath`.
+     *   - env: `vaultGitEnv(opts?.env)` (cwd-isolation + caller extras).
+     *   - On a spawn/exec error we capture the error `message` too, so a failure
+     *     before git could write to stderr (e.g. ENOENT) is NOT lost.
+     */
+    async runRaw(args, opts) {
+        const cwd = opts?.cwd === null ? undefined : (opts?.cwd ?? this.vaultPath);
+        try {
+            const { stdout, stderr } = await execFileAsync("git", ["--no-pager", "-c", "core.quotepath=false", ...args], {
+                // Generous buffer: file listings / porcelain output on a large vault
+                // can be sizable.
+                ...(cwd !== undefined ? { cwd } : {}),
+                maxBuffer: 64 * 1024 * 1024,
+                env: vaultGitEnv(opts?.env),
+            });
+            return { code: 0, stdout, stderr };
+        }
+        catch (err) {
+            const e = err;
+            return {
+                code: typeof e.code === "number" ? e.code : 1,
+                stdout: e.stdout ?? "",
+                // Preserve the error message when there is no stderr (e.g. a spawn
+                // failure like ENOENT, where promisified execFile sets stderr to an
+                // EMPTY STRING — so `||`, not `??`, to fall through to `message`).
+                stderr: e.stderr || e.message || "",
+            };
+        }
+    }
+    /**
+     * Ensure the vault directory exists and is an initialized git repo on `main`
+     * with an initial (empty) commit so branches exist. Idempotent: safe to call
+     * on every run. Sets a LOCAL bot identity for the vault repo if none is set
+     * (so engine commits never fall back to a global/unset identity).
+     */
+    async ensureRepo() {
+        await mkdir(this.vaultPath, { recursive: true });
+        if (!(await this.isRepo())) {
+            // `git init -b main` sets the initial branch on modern git; we still
+            // guard the branch name below for safety on older binaries.
+            await this.run(["init", "-b", DEFAULT_BRANCH]);
+        }
+        // Set a local identity for the vault repo if unset, so engine commits have
+        // a deterministic committer even on a machine with no global git config.
+        if (!(await this.hasLocalConfig("user.name"))) {
+            await this.run(["config", "user.name", BOT_AUTHOR_NAME]);
+        }
+        if (!(await this.hasLocalConfig("user.email"))) {
+            await this.run(["config", "user.email", BOT_AUTHOR_EMAIL]);
+        }
+        // Neutralize correctness-affecting git config in the vault's LOCAL config so
+        // a user's GLOBAL/system config cannot change porcelain BEHAVIOR (not just
+        // output) and corrupt the vault. The vault is OUR dedicated repo, so LOCAL
+        // values (which override global/system) are the right scope. Set
+        // UNCONDITIONALLY every run — idempotent and cheap; `git config <key>`
+        // writes to `--local` by default inside the repo. These MUST be in place
+        // before any add/commit/checkout that could be affected, hence they run
+        // before the initial-commit block below.
+        //   - core.autocrlf=false — CRITICAL (SPEC §11): a global core.autocrlf=true
+        //     would rewrite LF<->CRLF on add/checkout, making our deterministic,
+        //     byte-stable markdown churn and breaking the round-trip invariant.
+        //     `false` guarantees git stores/checks out verbatim bytes.
+        //   - core.safecrlf=false — avoid CRLF-related warnings/aborts on add.
+        //   - commit.gpgsign=false — the headless daemon must never try to GPG-sign
+        //     a commit (would fail/hang; we already set GIT_TERMINAL_PROMPT=0).
+        //   - core.attributesFile=/dev/null — neutralize the user's GLOBAL
+        //     gitattributes so a global clean/smudge filter (filter.<name>.clean)
+        //     cannot rewrite the STORED blob and break §11 byte-stability (a config
+        //     that core.autocrlf=false does not cover). POSIX-only path, which is
+        //     fine: the daemon runs on Linux (Docker) / macOS. A system
+        //     /etc/gitattributes remains the host admin's domain (out of scope).
+        // NOTE: these stay PERSISTED LOCAL config (not `-c` flags) on purpose — a
+        // human running git by hand in the vault must inherit the same neutralized
+        // behavior; a transient `-c` would not persist. (core.quotepath, by
+        // contrast, only affects OUR parsing of output and so is baked into the
+        // `runRaw` argv baseline instead.)
+        try {
+            await this.run(["config", "core.autocrlf", "false"]);
+            await this.run(["config", "core.safecrlf", "false"]);
+            await this.run(["config", "commit.gpgsign", "false"]);
+            await this.run(["config", "core.attributesFile", "/dev/null"]);
+        }
+        catch (err) {
+            const detail = err instanceof Error ? err.message : String(err);
+            throw new Error(`failed to pin vault git config (SPEC §11) — ensure ${this.vaultPath}` +
+                "/.git/config is writable and not locked (e.g. stale config.lock): " +
+                detail);
+        }
+        // Create the initial empty commit on `main` if the repo has no commits yet,
+        // so both `main` and (later) `docmost` branches have a common base.
+        if (!(await this.hasAnyCommit())) {
+            // Make sure we are on the default branch before the first commit (covers
+            // the older-git case where `init -b` was not honored).
+            await this.run(["checkout", "-B", DEFAULT_BRANCH]);
+            await this.commitRaw("init vault", {
+                authorName: BOT_AUTHOR_NAME,
+                authorEmail: BOT_AUTHOR_EMAIL,
+                allowEmpty: true,
+            });
+        }
+    }
+    /** True if `cwd` is inside a git work-tree (the vault is initialized). */
+    async isRepo() {
+        const r = await this.runRaw(["rev-parse", "--is-inside-work-tree"]);
+        return r.code === 0 && r.stdout.trim() === "true";
+    }
+    /** True if a LOCAL git config key is set in the vault repo. */
+    async hasLocalConfig(key) {
+        const r = await this.runRaw(["config", "--local", "--get", key]);
+        return r.code === 0 && r.stdout.trim().length > 0;
+    }
+    /** True if the repo has at least one commit (HEAD resolves). */
+    async hasAnyCommit() {
+        const r = await this.runRaw(["rev-parse", "--verify", "HEAD"]);
+        return r.code === 0;
+    }
+    /** True if a branch with the given name exists. */
+    async branchExists(name) {
+        const r = await this.runRaw([
+            "rev-parse",
+            "--verify",
+            `refs/heads/${name}`,
+        ]);
+        return r.code === 0;
+    }
+    /**
+     * Create `name` from `fromBranch` if it does not already exist. No-op (and no
+     * checkout) when the branch is already present.
+     */
+    async ensureBranch(name, fromBranch) {
+        if (await this.branchExists(name))
+            return;
+        await this.run(["branch", name, fromBranch]);
+    }
+    /** Name of the currently checked-out branch. */
+    async currentBranch() {
+        return this.run(["rev-parse", "--abbrev-ref", "HEAD"]);
+    }
+    /** Check out an existing branch. */
+    async checkout(name) {
+        await this.run(["checkout", name]);
+    }
+    /** Stage everything (adds, modifications, deletions). */
+    async stageAll() {
+        await this.run(["add", "-A"]);
+    }
+    /**
+     * True if the vault is mid-merge (an unresolved merge from a previous run,
+     * SPEC §9 / §12). Detected via a `MERGE_HEAD` ref OR any unmerged
+     * (conflicted) index entries (`git ls-files -u`). The pull cycle checks this
+     * BEFORE any checkout so a left-over merge produces a clear, actionable
+     * message instead of a raw "you need to resolve your current index first"
+     * failure deep inside `checkout`. This is what makes re-runs converge
+     * (resumability, SPEC §12).
+     */
+    async isMergeInProgress() {
+        // MERGE_HEAD exists exactly while a merge is in progress.
+        const mergeHead = await this.runRaw([
+            "rev-parse",
+            "--verify",
+            "--quiet",
+            "MERGE_HEAD",
+        ]);
+        if (mergeHead.code === 0 && mergeHead.stdout.trim().length > 0)
+            return true;
+        // Fallback / belt-and-suspenders: any unmerged index entries also mean the
+        // working tree is mid-conflict and a checkout would refuse.
+        const unmerged = await this.runRaw(["ls-files", "-u"]);
+        return unmerged.code === 0 && unmerged.stdout.trim().length > 0;
+    }
+    /**
+     * Commit the currently STAGED changes with an explicit author/committer
+     * identity and the given trailers appended to the message body (SPEC §7.3
+     * provenance). Returns `true` if a commit was made, `false` if there was
+     * nothing to commit (graceful no-op). The caller is expected to have staged
+     * its changes first (e.g. via `stageAll`).
+     */
+    async commit(message, opts) {
+        // Nothing staged -> nothing to commit. Treat as a no-op (SPEC §11: a
+        // deterministic re-pull of unchanged pages produces identical bytes, so
+        // git sees no diff and we must not error).
+        const staged = await this.runRaw([
+            "diff",
+            "--cached",
+            "--quiet",
+        ]);
+        // `diff --cached --quiet` exits 0 when the index matches HEAD (nothing
+        // staged), 1 when there are staged changes.
+        if (staged.code === 0)
+            return false;
+        await this.commitRaw(message, opts);
+        return true;
+    }
+    /**
+     * Low-level commit used by both `commit` and `ensureRepo`'s initial commit.
+     * Builds the full message with appended trailers and sets author + committer
+     * identity via env vars (so the committer matches the author, not the repo
+     * default).
+     */
+    async commitRaw(message, opts) {
+        const fullMessage = buildCommitMessage(message, opts.trailers);
+        // `--no-verify` skips pre-commit/commit-msg hooks: a global core.hooksPath
+        // (or any injected hook) must never interfere with engine commits in our
+        // dedicated vault repo.
+        const args = ["commit", "--no-verify", "-m", fullMessage];
+        if (opts.allowEmpty)
+            args.push("--allow-empty");
+        // Route through the single `runRaw` primitive; set author + committer
+        // identity via env vars (so the committer matches the author, not the repo
+        // default). Throw via the same unified message on a non-zero exit.
+        const r = await this.runRaw(args, {
+            env: {
+                GIT_AUTHOR_NAME: opts.authorName,
+                GIT_AUTHOR_EMAIL: opts.authorEmail,
+                GIT_COMMITTER_NAME: opts.authorName,
+                GIT_COMMITTER_EMAIL: opts.authorEmail,
+            },
+        });
+        if (r.code !== 0) {
+            const detail = (r.stderr || r.stdout || "").trim();
+            throw new Error(`git ${args.join(" ")} failed: ${detail}`);
+        }
+    }
+    /**
+     * Merge `fromBranch` into the current branch (`git merge --no-edit`).
+     * Fast-forwards when possible; performs a real 3-way merge otherwise. Conflict
+     * state is SURFACED (returned), NOT auto-resolved (SPEC §9): the conflict
+     * markers are left in the worktree for manual resolution by a later increment,
+     * and — critically — nothing is pushed to Docmost (we never write to Docmost
+     * anyway).
+     */
+    async merge(fromBranch) {
+        const r = await this.runRaw(["merge", "--no-edit", fromBranch]);
+        const output = `${r.stdout}\n${r.stderr}`.trim();
+        if (r.code === 0) {
+            return { ok: true, conflict: false, output };
+        }
+        // A non-zero exit on merge most commonly means a conflict. Confirm by
+        // checking for unmerged paths (porcelain "U" status) so we don't mislabel
+        // an unrelated failure as a conflict.
+        const conflict = await this.hasUnmergedPaths();
+        return { ok: false, conflict, output };
+    }
+    /** True if the index has any unmerged (conflicted) paths. */
+    async hasUnmergedPaths() {
+        const r = await this.runRaw(["diff", "--name-only", "--diff-filter=U"]);
+        return r.code === 0 && r.stdout.trim().length > 0;
+    }
+    /**
+     * List tracked files on the current branch (paths relative to the vault
+     * root, forward-slash separated). An optional glob (a git pathspec) narrows
+     * the listing, e.g. `"*.md"`.
+     *
+     * The target wiki is RUSSIAN, so vault file names routinely contain Cyrillic
+     * (e.g. `Колонка.md`). With git's DEFAULT `core.quotepath=true`, `ls-files`
+     * returns non-ASCII paths octal-escaped and double-quoted (`"\320\232..."`),
+     * which `src/pull.ts` `readExisting` would then parse as garbage paths,
+     * breaking move/duplicate detection. We defeat that two ways at once:
+     *   - `core.quotepath=false` disables the octal-escape/quoting. It is now the
+     *     `runRaw` argv baseline (prepended to EVERY invocation), so we no longer
+     *     pass it inline here.
+     *   - `-z` emits NUL-delimited RAW UTF-8 paths (no quoting, no newline
+     *     ambiguity), which we split on `\0`.
+     * We read the RAW stdout (NOT the trimming `run()` helper, which would mangle
+     * the NUL-delimited bytes) and split on `\0`, dropping empty entries. Paths
+     * are returned verbatim — git already emits forward slashes.
+     */
+    async listTrackedFiles(glob) {
+        const r = await this.runRaw(["ls-files", "-z", ...(glob ? [glob] : [])]);
+        if (r.code !== 0) {
+            const detail = (r.stderr || r.stdout || "").trim();
+            throw new Error(`git ls-files failed: ${detail}`);
+        }
+        return r.stdout.split("\0").filter((p) => p.length > 0);
+    }
+    /**
+     * Diff two refs with `--name-status -M -z` and parse the NUL-delimited output
+     * (SPEC §6: the FS→Docmost push direction diffs `main` against
+     * `refs/docmost/last-pushed`). Rename detection is ON (`-M`), so a moved/renamed
+     * file is reported as a single `R` row with both its old and new path instead
+     * of a delete+add pair — that distinction is what lets the push planner tell a
+     * move from a delete+create (SPEC §8 "Move vs delete").
+     *
+     * `-z` makes git emit NUL-delimited RAW UTF-8 records (the Russian wiki has
+     * Cyrillic file names) with NO quoting/escaping. The record shape differs by
+     * status:
+     *   - A/M/D:  `status\0path\0`
+     *   - R/C:    `Rnnn\0oldPath\0newPath\0`  (nnn = similarity score, e.g. `R100`)
+     * We read the RAW stdout (not the trimming `run()` helper, which would mangle
+     * the NUL bytes), split on `\0`, drop the trailing empty entry, and walk the
+     * tokens pulling 1 or 2 path tokens per status. Paths are returned verbatim.
+     */
+    async diffNameStatus(fromRef, toRef) {
+        const r = await this.runRaw([
+            "diff",
+            "--name-status",
+            "-M",
+            "-z",
+            fromRef,
+            toRef,
+        ]);
+        if (r.code !== 0) {
+            const detail = (r.stderr || r.stdout || "").trim();
+            throw new Error(`git diff --name-status failed: ${detail}`);
+        }
+        // Tokens alternate: <status> <path...> <status> <path...> ... With `-z`,
+        // each token (status code AND each path) is its own NUL-delimited field.
+        const tokens = r.stdout.split("\0").filter((t) => t.length > 0);
+        const entries = [];
+        let i = 0;
+        while (i < tokens.length) {
+            const raw = tokens[i++];
+            // The status token is e.g. `A`, `M`, `D`, or `R100` / `C075`. The leading
+            // letter is the change kind; any trailing digits are the similarity score.
+            const letter = raw[0];
+            if (letter === "R" || letter === "C") {
+                const score = Number.parseInt(raw.slice(1), 10);
+                const oldPath = tokens[i++];
+                const path = tokens[i++];
+                if (oldPath === undefined || path === undefined)
+                    break; // malformed tail
+                entries.push({
+                    status: letter,
+                    path,
+                    oldPath,
+                    ...(Number.isFinite(score) ? { score } : {}),
+                });
+            }
+            else if (letter === "A" || letter === "M" || letter === "D") {
+                const path = tokens[i++];
+                if (path === undefined)
+                    break; // malformed tail
+                entries.push({ status: letter, path });
+            }
+            else {
+                // Unknown/other status (e.g. T type-change, U unmerged) — consume one
+                // path token defensively so the walk stays aligned, but do not emit it
+                // (the push planner only handles A/M/D/R/C).
+                i++;
+            }
+        }
+        return entries;
+    }
+    /**
+     * Resolve a ref/commit-ish to its full SHA, or `null` if it does not exist.
+     * `rev-parse --verify --quiet` exits non-zero (and prints nothing) for an
+     * unknown ref, so a non-zero exit maps cleanly to `null`. Used to read
+     * `refs/docmost/last-pushed` (SPEC §5) — which is absent before the first push.
+     */
+    async revParse(ref) {
+        const r = await this.runRaw(["rev-parse", "--verify", "--quiet", ref]);
+        if (r.code !== 0)
+            return null;
+        const sha = r.stdout.trim();
+        return sha.length > 0 ? sha : null;
+    }
+    /**
+     * Read a ref to its SHA, or `null` if unset. Thin alias over `revParse`,
+     * named for the push direction's marker `refs/docmost/last-pushed` (SPEC §5:
+     * "что из `main` уже отражено в Docmost").
+     */
+    async readRef(ref) {
+        return this.revParse(ref);
+    }
+    /**
+     * Point `ref` at `target` (`git update-ref <ref> <target>`). Used to advance
+     * `refs/docmost/last-pushed` to the just-pushed `main` commit after a push
+     * (SPEC §6 step 3 / §5). `target` may be a SHA or any commit-ish git accepts.
+     */
+    async updateRef(ref, target) {
+        await this.run(["update-ref", ref, target]);
+    }
+    /**
+     * Fast-forward `branch` to `toCommit` — but ONLY if it is a TRUE fast-forward,
+     * i.e. the current `branch` tip is an ancestor of `toCommit` (verified via
+     * `git merge-base --is-ancestor <branch> <toCommit>`). Used to advance the
+     * `docmost` mirror branch after a clean push (SPEC §6 step 3 / §10): once a
+     * push succeeds, Docmost already contains the pushed `main` content, so the
+     * mirror must reflect it — otherwise the NEXT pull would diff our own write
+     * back and re-pull it (loop-guard).
+     *
+     * SAFETY — never force, never clobber divergent history:
+     *   - If `branch` IS an ancestor of `toCommit`, advance it with
+     *     `git update-ref refs/heads/<branch> <toCommit>`. The `docmost` branch is
+     *     NOT checked out during a push (push works on `main`), so updating the ref
+     *     directly is safe and avoids any working-tree touch.
+     *   - If `branch` is NOT an ancestor (divergent / would-be non-fast-forward),
+     *     do NOT move it — return `{ ok: false, reason: 'not-fast-forward' }` and
+     *     let the caller log it. We must never overwrite a `docmost` history that
+     *     has commits the push base does not contain.
+     *
+     * Returns `{ ok: true }` when the branch was advanced (or already at
+     * `toCommit`, a degenerate fast-forward), `{ ok: false, reason }` otherwise.
+     * A missing `branch` or `toCommit` also yields `{ ok: false }` with a reason.
+     */
+    async fastForwardBranch(branch, toCommit) {
+        const branchRef = `refs/heads/${branch}`;
+        // Resolve both endpoints first so a missing ref is a clean refusal, not a
+        // confusing `merge-base` failure.
+        const branchSha = await this.revParse(branchRef);
+        if (branchSha === null) {
+            return { ok: false, reason: `branch ${branch} does not exist` };
+        }
+        const targetSha = await this.revParse(toCommit);
+        if (targetSha === null) {
+            return { ok: false, reason: `target ${toCommit} does not resolve` };
+        }
+        // Already at the target -> a no-op fast-forward (still ok).
+        if (branchSha === targetSha)
+            return { ok: true };
+        // `merge-base --is-ancestor A B` exits 0 iff A is an ancestor of B. Only a
+        // true ancestor is a fast-forward; anything else is divergent and refused.
+        const ancestor = await this.runRaw([
+            "merge-base",
+            "--is-ancestor",
+            branchSha,
+            targetSha,
+        ]);
+        if (ancestor.code !== 0) {
+            return { ok: false, reason: "not-fast-forward" };
+        }
+        // Safe to advance: the branch is not checked out during push, so a direct
+        // ref update avoids a checkout/working-tree touch.
+        await this.updateRef(branchRef, targetSha);
+        return { ok: true };
+    }
+    /**
+     * Read a file's content at a specific ref (`git show <ref>:<path>`), or `null`
+     * if the path does not exist there. Used by the push direction to read the
+     * PRE-IMAGE of a DELETED file (e.g. at `refs/docmost/last-pushed`) so its
+     * `docmost:meta` — and therefore its `pageId` — can be recovered to translate
+     * the deletion into a `delete_page` (SPEC §6/§8: only TRACKED files, i.e. ones
+     * that had a pageId, are deleted in Docmost). A non-zero exit (path absent at
+     * that ref) maps to `null` rather than throwing.
+     */
+    async showFileAtRef(ref, path) {
+        // `git show <ref>:<path>` requires the path relative to the repo root; pass
+        // it verbatim (forward-slash, matching `listTrackedFiles` / diff output).
+        const r = await this.runRaw(["show", `${ref}:${path}`]);
+        if (r.code !== 0)
+            return null;
+        return r.stdout;
+    }
+}
+/**
+ * Build the environment for a vault git invocation (SPEC §12 cwd-isolation).
+ * Used by the single `runRaw` primitive every git command flows through, so
+ * these pins apply uniformly (including the `git --version` preflight).
+ *
+ * cwd-isolation is this module's central safety guarantee: every git command
+ * MUST operate on the vault repo at `cwd: vaultPath` and nothing else. An
+ * inherited `GIT_DIR` / `GIT_WORK_TREE` in `process.env` would silently
+ * redirect the operation away from `cwd` (e.g. to the source repo or another
+ * checkout), defeating that guarantee. So we always strip them, regardless of
+ * whatever else the caller adds (author/committer identity, etc.).
+ *
+ * Exported for unit testing.
+ */
+export function vaultGitEnv(extra) {
+    const env = {
+        ...process.env,
+        // Locale-independent output (defense in depth). We never parse localized
+        // prose, but pinning the locale prevents a future regression where some
+        // git message we DO key on is translated by an inherited LC_ALL/LANG.
+        LC_ALL: "C",
+        LANG: "C",
+        // Never page (we already pass --no-pager, but a stray GIT_PAGER could still
+        // bite) and never block on an interactive prompt (e.g. credentials) — the
+        // daemon runs unattended and must not hang.
+        GIT_PAGER: "cat",
+        GIT_TERMINAL_PROMPT: "0",
+        ...extra,
+    };
+    delete env.GIT_DIR;
+    delete env.GIT_WORK_TREE;
+    return env;
+}
+/**
+ * Build a commit message body with trailer lines appended (SPEC §7.3). The
+ * trailers are separated from the subject by a blank line so `git interpret-
+ * trailers` / `git log --format=%(trailers)` parse them as trailers.
+ * Exported for unit testing.
+ */
+export function buildCommitMessage(subject, trailers) {
+    if (!trailers || trailers.length === 0)
+        return subject;
+    return `${subject}\n\n${trailers.join("\n")}`;
+}

packages/git-sync/build/engine/layout.d.ts

@@ -0,0 +1,44 @@
+/**
+ * Pure page-tree -> vault path mapping (SPEC §12).
+ *
+ * Given the flat list of page nodes for a space (as returned by
+ * `listAllSpacePages`), compute for every page a deterministic, collision-free
+ * destination: a folder path (root -> leaf ancestors) plus a file stem (the
+ * page's own name, no extension). This module is intentionally PURE and
+ * dependency-free apart from the sanitization helpers, so the whole tree ->
+ * path logic is unit-testable without any I/O. The names are COSMETIC; identity
+ * lives in each file's meta block (pageId / slugId).
+ */
+/** Flat page node as returned by `listAllSpacePages` (no content). */
+export interface PageNode {
+    id: string;
+    title?: string;
+    slugId?: string;
+    parentPageId?: string | null;
+    hasChildren?: boolean;
+}
+/** A page's resolved vault destination: folder path + file stem. */
+export interface VaultEntry {
+    /** Folder path, root -> leaf (the page's ancestors). Empty for a root page. */
+    segments: string[];
+    /** The page's own file name without extension. */
+    stem: string;
+}
+/**
+ * Build the full vault layout for a space.
+ *
+ * Returns a Map keyed by pageId -> `{ segments, stem }`. The result is
+ * deterministic for a given input and guarantees every full destination path
+ * (`[...segments, stem].join("/")`) is unique, so no page can silently overwrite
+ * another.
+ *
+ * Disambiguation is layered:
+ *   1. Sibling collisions (same sanitized title under the same parent) are
+ *      resolved with a stable ` ~<slugId>` suffix (the suffix is itself
+ *      sanitized, since slugId/id is untrusted data that must never inject a
+ *      path separator).
+ *   2. A final full-path pass catches residual collisions that sibling-scoping
+ *      cannot see — e.g. two pages whose parents are BOTH outside the input set
+ *      both bucket at the root with `segments: []`.
+ */
+export declare function buildVaultLayout(pages: PageNode[]): Map<string, VaultEntry>;

packages/git-sync/build/engine/layout.js

@@ -0,0 +1,170 @@
+/**
+ * Pure page-tree -> vault path mapping (SPEC §12).
+ *
+ * Given the flat list of page nodes for a space (as returned by
+ * `listAllSpacePages`), compute for every page a deterministic, collision-free
+ * destination: a folder path (root -> leaf ancestors) plus a file stem (the
+ * page's own name, no extension). This module is intentionally PURE and
+ * dependency-free apart from the sanitization helpers, so the whole tree ->
+ * path logic is unit-testable without any I/O. The names are COSMETIC; identity
+ * lives in each file's meta block (pageId / slugId).
+ */
+import { sanitizeTitle, disambiguate } from "./sanitize.js";
+/**
+ * Build the full vault layout for a space.
+ *
+ * Returns a Map keyed by pageId -> `{ segments, stem }`. The result is
+ * deterministic for a given input and guarantees every full destination path
+ * (`[...segments, stem].join("/")`) is unique, so no page can silently overwrite
+ * another.
+ *
+ * Disambiguation is layered:
+ *   1. Sibling collisions (same sanitized title under the same parent) are
+ *      resolved with a stable ` ~<slugId>` suffix (the suffix is itself
+ *      sanitized, since slugId/id is untrusted data that must never inject a
+ *      path separator).
+ *   2. A final full-path pass catches residual collisions that sibling-scoping
+ *      cannot see — e.g. two pages whose parents are BOTH outside the input set
+ *      both bucket at the root with `segments: []`.
+ */
+export function buildVaultLayout(pages) {
+    // Index pages by id so the parent chain can be walked. Guard against
+    // duplicate ids in the input (first one wins).
+    const byId = new Map();
+    for (const p of pages) {
+        if (p && p.id && !byId.has(p.id))
+            byId.set(p.id, p);
+    }
+    // Resolve each node's display name once, deterministically, tracking sibling
+    // collisions per parent. `usedBySibling` maps a parent key -> set of names
+    // already taken under that parent. The bucket key is the node's parent ONLY
+    // when that parent is actually present in `byId`; otherwise (null parent, or
+    // an orphan whose parent is outside the input set) the node buckets at
+    // `"__root__"`. This is critical: orphans land at the vault root (see
+    // `folderSegmentsFor`), so they MUST share the root bucket with real root
+    // pages to be disambiguated against each other here — making `nameById` final
+    // before any `segments` are computed, so no ancestor name can drift later.
+    const usedBySibling = new Map();
+    const nameById = new Map();
+    for (const p of pages) {
+        if (p && p.id && !nameById.has(p.id)) {
+            const parentKey = p.parentPageId && byId.has(p.parentPageId) ? p.parentPageId : "__root__";
+            nameById.set(p.id, nameForNode(p, parentKey, usedBySibling));
+        }
+    }
+    // Every id we index above MUST get a resolved name; this helper returns it
+    // and THROWS if it is somehow absent, rather than silently recomputing a
+    // DIFFERENT, non-disambiguated name (which would desync a folder segment from
+    // its target file).
+    const nameOf = (id) => {
+        const name = nameById.get(id);
+        if (name === undefined) {
+            throw new Error(`buildVaultLayout: no resolved name for page id ${id}`);
+        }
+        return name;
+    };
+    // Build the folder path for a page by walking parentPageId to the root. The
+    // page's OWN name is the file stem; its ancestors become folders. A `visited`
+    // guard prevents an infinite loop on a malformed parent cycle.
+    const folderSegmentsFor = (node) => {
+        const ancestors = [];
+        const visited = new Set();
+        let current = node.parentPageId
+            ? byId.get(node.parentPageId)
+            : undefined;
+        while (current && current.id && !visited.has(current.id)) {
+            visited.add(current.id);
+            ancestors.unshift(nameOf(current.id));
+            current = current.parentPageId
+                ? byId.get(current.parentPageId)
+                : undefined;
+        }
+        return ancestors;
+    };
+    // First pass: compute the provisional { segments, stem } for every node.
+    const layout = new Map();
+    for (const p of pages) {
+        if (!p || !p.id || layout.has(p.id))
+            continue;
+        layout.set(p.id, {
+            segments: folderSegmentsFor(p),
+            stem: nameOf(p.id),
+        });
+    }
+    // FOLDER-NOTE transform (native-Obsidian layout): a page WITH CHILDREN lives at
+    // `<…>/<stem>/<stem>.md` — its body is the folder-note INSIDE its own folder
+    // (LostPaul Folder Notes convention), and its children sit alongside it in that
+    // folder. A leaf stays `<…>/<stem>.md`. Children's segments already point into
+    // the parent's folder (folderSegmentsFor walks ancestor NAMES), so only the
+    // parent's own file relocates here; the sibling name pass above already made
+    // the parent name unique, so folder == file name stays consistent.
+    for (const p of pages) {
+        if (!p || !p.id)
+            continue;
+        const entry = layout.get(p.id);
+        if (entry && p.hasChildren) {
+            entry.segments = [...entry.segments, entry.stem];
+        }
+    }
+    // Final full-path uniqueness pass — a belt-and-suspenders safety net. Note
+    // that cross-bucket (orphan/root) collisions are now resolved in the name pass
+    // above (orphans share the "__root__" bucket), so ancestor names are final
+    // before `segments` are built and this pass should rarely/never re-stem an
+    // ancestor. It only re-stems the colliding LATER leaf via the sanitized
+    // slugId/id, then (if still colliding) appends the id.
+    //
+    // Process FOLDER-NOTES (pages with children) FIRST so a parent claims its
+    // canonical `<name>/<name>.md` before a same-named CHILD — the child (a leaf)
+    // is the one that disambiguates, never the folder-note.
+    const usedPaths = new Set();
+    const seenIds = new Set();
+    const pathKey = (e) => [...e.segments, e.stem].join("/");
+    const ordered = pages
+        .filter((p) => Boolean(p && p.id))
+        .sort((a, b) => Number(Boolean(b.hasChildren)) - Number(Boolean(a.hasChildren)));
+    for (const p of ordered) {
+        if (seenIds.has(p.id))
+            continue;
+        seenIds.add(p.id);
+        const entry = layout.get(p.id);
+        if (!entry)
+            continue;
+        if (usedPaths.has(pathKey(entry))) {
+            // First attempt: disambiguate the stem with the sanitized slugId (or id).
+            entry.stem = disambiguate(entry.stem, sanitizeTitle(p.slugId ?? p.id));
+            if (usedPaths.has(pathKey(entry))) {
+                // Still colliding: append the (sanitized) id as a last resort. The id
+                // is globally unique, so this always resolves the collision.
+                entry.stem = disambiguate(entry.stem, sanitizeTitle(p.id));
+            }
+        }
+        usedPaths.add(pathKey(entry));
+    }
+    return layout;
+}
+/**
+ * Compute a deterministic, collision-free name for a node among its SIBLINGS.
+ * `usedBySibling` maps a parent key -> set of names already taken, so two
+ * siblings that sanitize to the same name get a stable ` ~slugId` suffix
+ * (SPEC §12). The suffix is itself passed through `sanitizeTitle`, because the
+ * slugId/id is a second untrusted-data channel that must never leak a path
+ * separator into the name. `parentKey` is supplied by the caller (it resolves
+ * to `"__root__"` for root pages AND for orphans whose parent is outside the
+ * input set, so they share one bucket). The name is COSMETIC; identity lives in
+ * the meta block.
+ */
+function nameForNode(node, parentKey, usedBySibling) {
+    let used = usedBySibling.get(parentKey);
+    if (!used) {
+        used = new Set();
+        usedBySibling.set(parentKey, used);
+    }
+    let name = sanitizeTitle(node.title ?? "");
+    if (used.has(name)) {
+        // Sibling collision: disambiguate with the stable, sanitized slugId (fall
+        // back to the sanitized pageId if no slugId is present).
+        name = disambiguate(name, sanitizeTitle(node.slugId ?? node.id));
+    }
+    used.add(name);
+    return name;
+}

packages/git-sync/build/engine/loop-guard.d.ts

@@ -0,0 +1,13 @@
+/**
+ * Stable hash of a page's markdown BODY (SPEC §10 "хэш тела"). Deterministic:
+ * the same input string always yields the same digest, a different input a
+ * different one. Used to recognize our own write later (loop suppression).
+ *
+ * We hash the body STRING as-is (UTF-8) with SHA-256 and return lowercase hex.
+ * SPEC §10 keys on the body hash rather than file bytes; callers decide WHAT
+ * counts as "the body" (here it is the exact string passed in — typically the
+ * self-contained markdown that was pushed). No normalization is applied: the
+ * caller is responsible for passing a canonical/stable representation if it
+ * wants hash equality across cosmetic-only differences.
+ */
+export declare function bodyHash(markdownBody: string): string;

packages/git-sync/build/engine/loop-guard.js

@@ -0,0 +1,28 @@
+/**
+ * Loop-guard primitives (SPEC §10). The sync engine must never re-pull its OWN
+ * write as if it were a remote edit: after a push, the next poll will see the
+ * page it just wrote with a fresh `updatedAt`. To suppress that, we key on two
+ * signals — the body HASH of what we pushed (this module) and the `updatedAt`
+ * returned by the write — recorded per page at push time.
+ *
+ * This module owns the PURE, deterministic body-hash. The CONSUMPTION on the
+ * pull side (comparing an incoming page's body hash against the last pushed hash
+ * to decide "this is our own write, ignore it") is a future increment — here we
+ * only PRODUCE the hash and the per-page push record (see `src/push.ts`).
+ */
+import { createHash } from "node:crypto";
+/**
+ * Stable hash of a page's markdown BODY (SPEC §10 "хэш тела"). Deterministic:
+ * the same input string always yields the same digest, a different input a
+ * different one. Used to recognize our own write later (loop suppression).
+ *
+ * We hash the body STRING as-is (UTF-8) with SHA-256 and return lowercase hex.
+ * SPEC §10 keys on the body hash rather than file bytes; callers decide WHAT
+ * counts as "the body" (here it is the exact string passed in — typically the
+ * self-contained markdown that was pushed). No normalization is applied: the
+ * caller is responsible for passing a canonical/stable representation if it
+ * wants hash equality across cosmetic-only differences.
+ */
+export function bodyHash(markdownBody) {
+    return createHash("sha256").update(markdownBody, "utf8").digest("hex");
+}

packages/git-sync/build/engine/pull.d.ts

@@ -0,0 +1,136 @@
+import type { GitSyncClient } from "./client.types.js";
+import { type PageNode } from "./layout.js";
+import { VaultGit } from "./git.js";
+import { type MovedEntry, type DeletionDecision } from "./reconcile.js";
+/**
+ * Injectable IO for `readExisting` (R-Pull-1, test-strategy report §5). The real
+ * `main` wires these to `git.listTrackedFiles("*.md")` and an `fs.readFile`
+ * rooted at the vault; tests pass fakes so the parsing/skip rules are unit-
+ * testable without a real git repo or filesystem.
+ */
+export interface ReadExistingDeps {
+    /** List tracked .md paths (forward-slash, vault-relative). */
+    listTracked: () => Promise<string[]>;
+    /** Read a tracked file's text by its (forward-slash) vault-relative path. */
+    readFile: (relPath: string) => Promise<string>;
+}
+/**
+ * Read every tracked .md file in the vault and recover `{ pageId, relPath }` from
+ * its `gitmost_id` frontmatter (native-Obsidian format). Files without a
+ * `gitmost_id` are skipped (they are not engine-tracked pages yet — e.g. a stray
+ * hand-written Obsidian file; PUSH adopts those separately).
+ *
+ * The IO is injected (R-Pull-1) so this is testable with fakes. Skip rules:
+ *   - a `readFile` rejection (tracked but missing on disk, a mid-operation race)
+ *     -> skipped, NOT thrown; the next pull converges;
+ *   - no `gitmost_id` frontmatter (`parsePageFile` -> id null) -> skipped.
+ */
+export declare function readExisting(deps: ReadExistingDeps): Promise<{
+    pageId: string;
+    relPath: string;
+}[]>;
+/**
+ * Input to the PURE `computePullActions` (R-Pull-2). All data, no IO: the live
+ * tree nodes + completeness flag (from `listSpaceTree`) and the parsed
+ * `existing` tracked files (from `readExisting`).
+ */
+export interface PullActionsInput {
+    /** Live page nodes for the space (from `listSpaceTree`). */
+    pages: PageNode[];
+    /** Whether the live tree fetch was COMPLETE (SPEC §8 suppression). */
+    treeComplete: boolean;
+    /** Parsed tracked files: `{ pageId, relPath }` (from `readExisting`). */
+    existing: {
+        pageId: string;
+        relPath: string;
+    }[];
+}
+/**
+ * The PURE decisions object computed by `computePullActions` (no IO). It holds
+ * the reconciliation plan plus the SPEC §8 absence-deletion decision, with the
+ * suppression already folded in: `toDelete` is the POST-suppression set the
+ * caller should actually remove (empty when `deletionDecision.apply` is false).
+ */
+export interface PullActions {
+    /** Pages to (re)write at their relPath (add + update + move target). */
+    toWrite: {
+        pageId: string;
+        relPath: string;
+    }[];
+    /** Moves: write new path, then remove old path (only on a successful write). */
+    moved: MovedEntry[];
+    /**
+     * Absence-based paths to delete AFTER suppression. Empty when the decision
+     * suppressed deletions this cycle, so the caller can apply it unconditionally.
+     */
+    toDelete: string[];
+    /** Why absence deletions were (or were not) applied (for logging + tests). */
+    deletionDecision: DeletionDecision;
+    /** Tracked-file count (for the suppression log messages). */
+    existingCount: number;
+    /** Planned absence-delete count BEFORE suppression (for the log message). */
+    plannedDeleteCount: number;
+}
+/**
+ * PURE pull-action planner (R-Pull-2, test-strategy report §5). Takes the live
+ * tree nodes + completeness + existing tracked files and returns the full set of
+ * decisions with NO IO:
+ *
+ *   - builds the vault layout (deterministic relPath per live page),
+ *   - `planReconciliation` -> toWrite / moved / absence-toDelete,
+ *   - `decideAbsenceDeletions` -> the SPEC §8 suppression (incomplete-fetch +
+ *     empty-live + mass-delete guard), folded IN here so `toDelete` is the
+ *     POST-suppression set (empty when suppressed).
+ *
+ * Moves are NOT governed by the suppression: a moved page is present in `live`,
+ * so its old-path removal is real (the caller still gates it on the write
+ * succeeding). The expensive content fetch / file write / git ops happen in the
+ * thin `applyPullActions`.
+ */
+export declare function computePullActions(input: PullActionsInput): PullActions;
+/**
+ * Injectable IO for `applyPullActions` (R-Pull-2). The real `main` wires these
+ * to the live client, the vault git wrapper, and `node:fs/promises`; tests pass
+ * fakes that RECORD calls so the ordering + the move-on-success data-loss guard
+ * are testable without real git/fs/network.
+ */
+export interface ApplyPullActionsDeps {
+    client: Pick<GitSyncClient, "getPageJson">;
+    git: Pick<VaultGit, "stageAll" | "commit" | "checkout" | "merge">;
+    /** Write a file by ABSOLUTE path (mkdir of the parent is done internally). */
+    writeFile: (absPath: string, text: string) => Promise<void>;
+    /** Recursive mkdir of an ABSOLUTE directory path. */
+    mkdir: (absDir: string) => Promise<void>;
+    /** Remove a file by ABSOLUTE path (force: a missing file is a no-op). */
+    rm: (absPath: string) => Promise<void>;
+}
+/** Outcome counters from `applyPullActions` (for the summary + tests). */
+export interface ApplyResult {
+    written: number;
+    movedApplied: number;
+    deleted: number;
+    failed: number;
+    committed: boolean;
+    merge: {
+        ok: boolean;
+        conflict: boolean;
+        output: string;
+    };
+}
+/**
+ * THIN IO applier (R-Pull-2). Performs the side effects in the EXACT current
+ * order, with all the original safety guards preserved bit-for-bit:
+ *
+ *   1. for each `toWrite`: fetch content (`client.getPageJson`) -> stabilize
+ *      (normalize-on-write fixpoint, SPEC §11) -> mkdir + write. One bad page
+ *      never aborts the pull (bounded-concurrency pool, fault-tolerant).
+ *   2. apply MOVE old-path removals — ONLY when the planner marked the old path
+ *      removable AND the new-path write SUCCEEDED (the ⭐ data-loss guard: a
+ *      failed move-write keeps the old path so the page never vanishes).
+ *   3. apply (post-suppression) absence deletes.
+ *   4. stageAll + commit on `docmost` (subject from ACTUAL written/deleted
+ *      counts) + checkout main + merge docmost (conflicts surfaced, SPEC §9).
+ *
+ * `vaultRoot` roots the relPath -> absolute-path conversion for the fs deps.
+ */
+export declare function applyPullActions(deps: ApplyPullActionsDeps, actions: PullActions, vaultRoot: string): Promise<ApplyResult>;

packages/git-sync/build/engine/pull.js

@@ -0,0 +1,284 @@
+/**
+ * Pull cycle — Docmost -> vault (SPEC §6 "Docmost -> ФС").
+ *
+ * This increment turns the read-only mirror into the git-backed pull cycle:
+ *
+ *   1. ensureRepo(vault); refuse if a merge is in progress (SPEC §9/§12);
+ *      ensureBranch("docmost", "main")   (SPEC §5 branches)
+ *   2. checkout docmost
+ *   3. fetch the live tree (listSpaceTree -> {pages, complete}) -> compute the
+ *      desired `live` files (relPath via the pure sanitize/disambiguation layout)
+ *   4. parse `existing` tracked .md files (pageId + relPath from gitmost_id frontmatter)
+ *   5. plan = planReconciliation(live, existing)   (pure, SPEC §5/§8); toDelete
+ *      is absence-only, moves are separate
+ *   6. decideAbsenceDeletions: SUPPRESS absence deletions on an incomplete tree
+ *      fetch (SPEC §8) and behind the mass-delete guard (defense in depth)
+ *   7. write each live page in its fixpoint form (normalize-on-write, SPEC §11);
+ *      apply moved-old-path removals (only when the move write SUCCEEDED) and
+ *      absence-delete removals (only when the decision allowed them)
+ *   8. stageAll + commit on `docmost` with the provenance trailer (SPEC §7.3)
+ *   9. checkout main + merge docmost (conflicts are surfaced, NOT auto-resolved,
+ *      SPEC §9); push is deferred (SPEC §7)
+ *  10. one-line summary
+ *
+ * DIRECTION IS Docmost -> vault ONLY. Nothing here ever writes to Docmost
+ * (read-only: listSpaceTree + getPageJson). All git operations run against
+ * the vault repo (`cwd = vaultPath`), never the source repo (see ./git.ts).
+ *
+ * The client seam is the native `GitSyncClient` (`Pick<GitSyncClient, ...>`);
+ * the gitmost server drives the engine in-process (there is no standalone CLI
+ * entry point).
+ */
+import { dirname } from "node:path";
+import { sep } from "node:path";
+import { parsePageFile, serializePageFile } from "../lib/page-file.js";
+import { buildVaultLayout } from "./layout.js";
+import { BOT_AUTHOR_NAME, BOT_AUTHOR_EMAIL, DEFAULT_BRANCH, } from "./git.js";
+import { planReconciliation, decideAbsenceDeletions, } from "./reconcile.js";
+import { stabilizePageBody } from "./stabilize.js";
+// Engine-only mirror branch (SPEC §5): the engine writes here, humans never do.
+const DOCMOST_BRANCH = "docmost";
+// Machine-readable provenance the loop-guard keys on (SPEC §7.3 / §12).
+const SOURCE_TRAILER = "Docmost-Sync-Source: docmost";
+// Number of pages fetched/stabilized concurrently. Bounded so a large space
+// does not open thousands of simultaneous requests/conversions at once.
+const CONCURRENCY = 6;
+// How often to log incremental progress (every N completed pages).
+const PROGRESS_EVERY = 25;
+/** Convert a vault-relative path (forward-slash) to an absolute FS path. */
+function relToAbs(vaultRoot, relPath) {
+    return [vaultRoot, ...relPath.split("/")].join("/");
+}
+/** Convert an absolute/relative segment list under the vault to a relPath. */
+function segmentsToRelPath(segments, stem) {
+    return [...segments, `${stem}.md`].join("/");
+}
+/**
+ * Read every tracked .md file in the vault and recover `{ pageId, relPath }` from
+ * its `gitmost_id` frontmatter (native-Obsidian format). Files without a
+ * `gitmost_id` are skipped (they are not engine-tracked pages yet — e.g. a stray
+ * hand-written Obsidian file; PUSH adopts those separately).
+ *
+ * The IO is injected (R-Pull-1) so this is testable with fakes. Skip rules:
+ *   - a `readFile` rejection (tracked but missing on disk, a mid-operation race)
+ *     -> skipped, NOT thrown; the next pull converges;
+ *   - no `gitmost_id` frontmatter (`parsePageFile` -> id null) -> skipped.
+ */
+export async function readExisting(deps) {
+    const tracked = await deps.listTracked();
+    const existing = [];
+    for (const relPath of tracked) {
+        // git ls-files always emits forward-slash paths; normalize just in case.
+        const rel = relPath.split(sep).join("/");
+        let text;
+        try {
+            text = await deps.readFile(rel);
+        }
+        catch {
+            // Tracked but missing on disk (mid-operation race) — skip; the next pull
+            // converges.
+            continue;
+        }
+        const { id } = parsePageFile(text);
+        if (id)
+            existing.push({ pageId: id, relPath: rel });
+    }
+    return existing;
+}
+/**
+ * PURE pull-action planner (R-Pull-2, test-strategy report §5). Takes the live
+ * tree nodes + completeness + existing tracked files and returns the full set of
+ * decisions with NO IO:
+ *
+ *   - builds the vault layout (deterministic relPath per live page),
+ *   - `planReconciliation` -> toWrite / moved / absence-toDelete,
+ *   - `decideAbsenceDeletions` -> the SPEC §8 suppression (incomplete-fetch +
+ *     empty-live + mass-delete guard), folded IN here so `toDelete` is the
+ *     POST-suppression set (empty when suppressed).
+ *
+ * Moves are NOT governed by the suppression: a moved page is present in `live`,
+ * so its old-path removal is real (the caller still gates it on the write
+ * succeeding). The expensive content fetch / file write / git ops happen in the
+ * thin `applyPullActions`.
+ */
+export function computePullActions(input) {
+    const { pages, treeComplete, existing } = input;
+    const layout = buildVaultLayout(pages);
+    const live = [];
+    for (const p of pages) {
+        if (!p || !p.id)
+            continue;
+        const entry = layout.get(p.id);
+        if (!entry)
+            continue;
+        live.push({
+            pageId: p.id,
+            relPath: segmentsToRelPath(entry.segments, entry.stem),
+        });
+    }
+    // Plan reconciliation (pure). `plan.toDelete` is ABSENCE-based only;
+    // `plan.moved` carries move old-path removals separately.
+    const plan = planReconciliation(live, existing);
+    // Decide whether the ABSENCE-based deletions may be applied this cycle
+    // (SPEC §8): incomplete-fetch suppression + empty-live + mass-delete guard.
+    // Moves are NOT governed by this.
+    const deletionDecision = decideAbsenceDeletions({
+        treeComplete,
+        liveCount: live.length,
+        existingCount: existing.length,
+        deleteCount: plan.toDelete.length,
+    });
+    return {
+        toWrite: plan.toWrite,
+        moved: plan.moved,
+        // Fold the suppression in: a suppressed cycle deletes nothing.
+        toDelete: deletionDecision.apply ? plan.toDelete : [],
+        deletionDecision,
+        existingCount: existing.length,
+        plannedDeleteCount: plan.toDelete.length,
+    };
+}
+/**
+ * THIN IO applier (R-Pull-2). Performs the side effects in the EXACT current
+ * order, with all the original safety guards preserved bit-for-bit:
+ *
+ *   1. for each `toWrite`: fetch content (`client.getPageJson`) -> stabilize
+ *      (normalize-on-write fixpoint, SPEC §11) -> mkdir + write. One bad page
+ *      never aborts the pull (bounded-concurrency pool, fault-tolerant).
+ *   2. apply MOVE old-path removals — ONLY when the planner marked the old path
+ *      removable AND the new-path write SUCCEEDED (the ⭐ data-loss guard: a
+ *      failed move-write keeps the old path so the page never vanishes).
+ *   3. apply (post-suppression) absence deletes.
+ *   4. stageAll + commit on `docmost` (subject from ACTUAL written/deleted
+ *      counts) + checkout main + merge docmost (conflicts surfaced, SPEC §9).
+ *
+ * `vaultRoot` roots the relPath -> absolute-path conversion for the fs deps.
+ */
+export async function applyPullActions(deps, actions, vaultRoot) {
+    const { client, git } = deps;
+    // Emit the SPEC §8 suppression warnings (preserved from the original `main`).
+    const decision = actions.deletionDecision;
+    if (!decision.apply) {
+        if (decision.reason === "incomplete-fetch") {
+            console.warn("pull: tree fetch incomplete — deletions suppressed this cycle (SPEC §8)");
+        }
+        else if (decision.reason === "empty-live") {
+            console.warn(`pull: live fetch returned 0 pages but ${actions.existingCount} file(s) are ` +
+                `tracked — deletions suppressed this cycle (SPEC §8). Re-run when ` +
+                `Docmost is reachable.`);
+        }
+        else {
+            console.warn(`pull: plan would delete ${actions.plannedDeleteCount} of ${actions.existingCount} ` +
+                `tracked file(s) (mass-delete guard) — deletions suppressed this ` +
+                `cycle (SPEC §8). Verify the live Docmost tree, then re-run.`);
+        }
+    }
+    // 1. Write each live page in its fixpoint form (normalize-on-write, SPEC §11).
+    let written = 0;
+    let failed = 0;
+    let completed = 0;
+    let nextIndex = 0;
+    // pageIds whose write FAILED. A moved page whose new-path write failed must
+    // NOT have its old path removed (otherwise the page vanishes entirely).
+    const failedPageIds = new Set();
+    const writeOne = async (w) => {
+        try {
+            const page = await client.getPageJson(w.pageId);
+            // Native-Obsidian format: a minimal `gitmost_id` frontmatter + the fixpoint
+            // markdown body. title/parent/space are DERIVED (filename / folder / repo),
+            // so nothing but the pageId is persisted as meta.
+            const text = serializePageFile(page.id, await stabilizePageBody(page.content));
+            const abs = relToAbs(vaultRoot, w.relPath);
+            await deps.mkdir(dirname(abs));
+            await deps.writeFile(abs, text);
+            written++;
+        }
+        catch (err) {
+            failed++;
+            failedPageIds.add(w.pageId);
+            console.error(`pull: failed page ${w.pageId}:`, err instanceof Error ? err.message : String(err));
+        }
+        finally {
+            completed++;
+            if (completed % PROGRESS_EVERY === 0) {
+                console.log(`pulled ${completed}/${actions.toWrite.length}`);
+            }
+        }
+    };
+    // Bounded-concurrency pool (dependency-free): a fixed set of runners each
+    // take the next index until the write list is exhausted. One bad page never
+    // aborts the whole pull (mirrors the fault-tolerant tree walk).
+    const runner = async () => {
+        while (true) {
+            const i = nextIndex++;
+            if (i >= actions.toWrite.length)
+                return;
+            await writeOne(actions.toWrite[i]);
+        }
+    };
+    await Promise.all(Array.from({ length: Math.min(CONCURRENCY, actions.toWrite.length) || 1 }, () => runner()));
+    // Helper: `rm` with force:true is a no-op if the file is already gone.
+    const removePath = async (rel, what) => {
+        try {
+            await deps.rm(relToAbs(vaultRoot, rel));
+            return true;
+        }
+        catch (err) {
+            console.error(`pull: failed to ${what} ${rel}:`, err instanceof Error ? err.message : String(err));
+            return false;
+        }
+    };
+    // 2. Apply MOVE old-path removals. A moved page IS present in `live`, so its
+    //    old path is genuinely stale — NOT subject to the incomplete-fetch
+    //    suppression. BUT only remove the old path when (a) the planner marked it
+    //    removable (not reused by another live page) AND (b) the new-path write
+    //    actually SUCCEEDED — otherwise we would delete the only copy of a page
+    //    whose move-write failed (⭐ data-loss guard).
+    let movedApplied = 0;
+    for (const m of actions.moved) {
+        if (!m.removeOldPath)
+            continue;
+        if (failedPageIds.has(m.pageId)) {
+            console.warn(`pull: move write for ${m.pageId} failed — keeping old path ` +
+                `${m.fromRelPath} (SPEC §8)`);
+            continue;
+        }
+        if (await removePath(m.fromRelPath, "remove moved old path"))
+            movedApplied++;
+    }
+    // 3. Apply ABSENCE-based deletions — `actions.toDelete` is ALREADY the
+    //    post-suppression set (empty when the decision suppressed them, SPEC §8).
+    let deleted = 0;
+    for (const rel of actions.toDelete) {
+        if (await removePath(rel, "delete"))
+            deleted++;
+    }
+    // 4. Stage + commit on `docmost` (only if there is something to commit).
+    //    Deterministic stabilized output means unchanged pages produce identical
+    //    bytes -> git sees no diff -> no churn (SPEC §11). The subject reflects the
+    //    ACTUAL work applied (pages written + files deleted), not the planned size,
+    //    so a run with failures does not over-report (SPEC §5 nit).
+    const subject = deleted > 0
+        ? `docmost: sync ${written} page(s), ${deleted} deleted`
+        : `docmost: sync ${written} page(s)`;
+    await git.stageAll();
+    const committed = await git.commit(subject, {
+        authorName: BOT_AUTHOR_NAME,
+        authorEmail: BOT_AUTHOR_EMAIL,
+        trailers: [SOURCE_TRAILER],
+    });
+    // Merge docmost -> main. Conflicts are surfaced and left in git (SPEC §9);
+    // we never push to Docmost. Push to a git remote is deferred (SPEC §7).
+    await git.checkout(DEFAULT_BRANCH);
+    const merge = await git.merge(DOCMOST_BRANCH);
+    if (merge.conflict) {
+        console.error("pull: merge of docmost -> main CONFLICTED. Conflict markers were left " +
+            "in the vault for manual resolution (SPEC §9). Nothing is pushed to " +
+            "Docmost (read-only). Resolve locally, then re-run.");
+    }
+    else if (!merge.ok) {
+        console.error(`pull: merge of docmost -> main failed: ${merge.output}`);
+    }
+    console.log("pull: git push to remote is DEFERRED in this increment (SPEC §7).");
+    return { written, movedApplied, deleted, failed, committed, merge };
+}

packages/git-sync/build/engine/push.d.ts

@@ -0,0 +1,504 @@
+/**
+ * Push cycle — vault -> Docmost (SPEC §6 "ФС → Docmost"), FIRST increment.
+ *
+ * This module mirrors the structure of `./pull.ts`: a set of VaultGit diff/ref
+ * primitives (in `./git.ts`), a PURE planner (`computePushActions`) that turns
+ * a git diff into a classified action set with NO IO, and a THIN injectable
+ * applier (`applyPushActions`) exercised in tests via fakes only.
+ *
+ * Direction is vault -> Docmost. The diff is `main` against
+ * `refs/docmost/last-pushed` (SPEC §6 step 2); each `A`/`M`/`D`/`R` row is
+ * translated into a Docmost mutation by `pageId` identity (SPEC §4):
+ *   - A without pageId   -> create_page (then write the assigned pageId back).
+ *   - A with    pageId   -> update (restored/copied file; the page already exists).
+ *   - M                  -> update content (collab/Yjs path, SPEC §2/§15.6).
+ *   - D                  -> delete_page (pageId recovered from the PRE-IMAGE meta).
+ *   - R                  -> rename/move (CLASSIFIED here, APPLIED in push #3).
+ *
+ * MOVE/RENAME APPLY (push #3) — DONE here. `classifyRenameMoves` (PURE) resolves
+ * each `renamesMoves` entry into the Docmost op(s) it needs, comparing the PATH-
+ * derived parent (SPEC §5: the file path is the source of truth for tree
+ * position, NOT stale `meta.parentPageId`) and the meta title; `applyPushActions`
+ * then calls `move_page` / `rename_page` (both for a reparent+retitle), or
+ * records a NO-OP for a cosmetic local-only file-path rename.
+ *
+ * The client seam is the native `GitSyncClient` (`Pick<GitSyncClient, ...>`);
+ * the gitmost server drives the engine in-process (there is no standalone CLI
+ * entry point).
+ */
+import { type DocmostMdMeta } from "../lib/index.js";
+import type { GitSyncClient } from "./client.types.js";
+import type { DiffEntry } from "./git.js";
+import { VaultGit } from "./git.js";
+import { type Settings } from "./settings.js";
+export type { DiffEntry } from "./git.js";
+/** A page to CREATE in Docmost (new local file, meta has no pageId yet). */
+export interface CreateAction {
+    /** Vault-relative path of the new file. */
+    path: string;
+}
+/** A page whose CONTENT changed (meta carries the existing pageId). */
+export interface UpdateAction {
+    pageId: string;
+    /** Vault-relative path of the changed file. */
+    path: string;
+}
+/** A page to soft-delete in Docmost (Trash, SPEC §8). */
+export interface DeleteAction {
+    pageId: string;
+}
+/** A renamed/moved page (same pageId, new path). Resolution DEFERRED. */
+export interface RenameMoveAction {
+    pageId: string;
+    oldPath: string;
+    newPath: string;
+}
+/**
+ * A CLASSIFIED rename/move (push #3): a `RenameMoveAction` resolved into the
+ * Docmost op(s) it actually needs. The file PATH is the source of truth for tree
+ * position (SPEC §5: "истина связи — pageId, не путь" — the path is COSMETIC and
+ * LOCAL, the page identity is its pageId), so we compare the RESOLVED parent of
+ * the new path against the resolved parent of the old path, and the title in the
+ * current meta against the title in the previous meta. Each sub-op is emitted
+ * ONLY when something real changed:
+ *   - `move`  — the resolved parent page changed (reparent in Docmost). A `null`
+ *     `parentPageId` means the new parent is ROOT (the file sits at the space
+ *     root, no enclosing folder).
+ *   - `rename` — the page title changed (a pure title edit in Docmost).
+ *   - `noop`  — neither changed: a purely LOCAL file-path rename (same parent,
+ *     same title). The page identity is its pageId, so Docmost is NOT called.
+ * `move` and `rename` are independent and may BOTH be present (reparent + retitle).
+ */
+export interface RenameMoveActionClassified {
+    pageId: string;
+    oldPath: string;
+    newPath: string;
+    /** Present iff the resolved parent changed -> `move_page` (reparent). */
+    move?: {
+        parentPageId: string | null;
+    };
+    /** Present iff the title changed -> `rename_page` (title-only). */
+    rename?: {
+        title: string;
+    };
+    /** True iff neither parent nor title changed (cosmetic local-only rename). */
+    noop?: true;
+}
+/**
+ * Injected resolvers for the PURE `classifyRenameMoves` (push #3). Both are PURE
+ * given a path + side; the real `main` (a follow-up) wires them to the file tree
+ * (`readFile` for `current`, `git.showFileAtRef` for `prev`), tests pass plain
+ * lookups. SPEC §5 path-as-truth:
+ *   - `metaAt`: the file's synthetic native meta at that side (title from the
+ *     filename, pageId from the `gitmost_id` frontmatter).
+ *   - `resolveParentPageId`: the pageId of the page whose FILE is the parent
+ *     FOLDER's `.md` (one level up from the given path), or `null` for ROOT.
+ */
+export interface ClassifyRenameMovesDeps {
+    metaAt: (path: string, side: MetaSide) => DocmostMdMeta | null;
+    resolveParentPageId: (path: string, side: MetaSide) => string | null;
+}
+/**
+ * PURE classifier for the `renamesMoves` produced by `computePushActions`
+ * (push #3, SPEC §5/§6/§8). Resolves each `{pageId, oldPath, newPath}` into the
+ * Docmost op(s) it needs, with NO IO (both resolvers are injected).
+ *
+ * SPEC §5 — the file PATH is the source of truth for tree position, NOT the
+ * (possibly stale) `meta.parentPageId`. So the NEW parent is resolved from
+ * `newPath`'s enclosing folder, and the OLD parent from `oldPath`'s enclosing
+ * folder, via `deps.resolveParentPageId`. The title comes from the meta.
+ *
+ * For each entry:
+ *   - `newParent = resolveParentPageId(newPath, 'current')`,
+ *     `oldParent = resolveParentPageId(oldPath, 'prev')`.
+ *   - `newTitle = metaAt(newPath,'current')?.title`,
+ *     `oldTitle = metaAt(oldPath,'prev')?.title`.
+ *   - include `move` iff `newParent !== oldParent` (a real reparent),
+ *   - include `rename` iff `newTitle` is a NON-EMPTY string AND differs from
+ *     `oldTitle` (a real title edit; an empty/absent new title is never a rename),
+ *   - if NEITHER applies -> `noop: true` (a cosmetic local-only file-path rename;
+ *     the page is its pageId, so Docmost is not touched).
+ */
+export declare function classifyRenameMoves(renamesMoves: RenameMoveAction[], deps: ClassifyRenameMovesDeps): RenameMoveActionClassified[];
+/** The classified set of push actions (PURE output of `computePushActions`). */
+export interface PushActions {
+    creates: CreateAction[];
+    updates: UpdateAction[];
+    deletes: DeleteAction[];
+    renamesMoves: RenameMoveAction[];
+    /**
+     * Diff rows that could NOT be classified into an action, with a reason — e.g.
+     * a deleted file whose PRE-IMAGE meta carried no recoverable pageId (the
+     * untracked-file guard, SPEC §8: only files that were tracked with a pageId
+     * are deleted in Docmost). Carried so the caller can log them.
+     */
+    skipped: {
+        path: string;
+        status: DiffEntry["status"];
+        reason: string;
+    }[];
+}
+/**
+ * Which tree a `metaAt` lookup reads the file's native meta from:
+ *   - `current`: the current `main` tree (the live file content) — used for
+ *     A/M/R, where the file still exists.
+ *   - `prev`: the last-pushed PRE-IMAGE (e.g. `refs/docmost/last-pushed:<path>`)
+ *     — used for D, where the file is gone from `main` but its pageId must be
+ *     recovered from the version Docmost last knew (SPEC §6/§8).
+ */
+export type MetaSide = "current" | "prev";
+/** Input to the PURE planner. `metaAt` is injected (no IO inside the planner). */
+export interface PushActionsInput {
+    /** Diff rows of `main` vs `refs/docmost/last-pushed` (SPEC §6 step 2). */
+    changes: DiffEntry[];
+    /**
+     * Resolve a file's synthetic native meta at a given side, or `null` if the file is
+     * absent there / has no parseable meta. PURE injection: the real `main` reads
+     * the working tree (current) or `git show <last-pushed>:<path>` (prev); tests
+     * pass a plain lookup.
+     */
+    metaAt: (path: string, side: MetaSide) => DocmostMdMeta | null;
+    /**
+     * The pageIds present at ANY path in the current `main` tree (optional). When
+     * given, a deleted file whose pageId still lives somewhere in the tree is NOT
+     * a deletion but a MOVE — guards against trashing a live page when a layout
+     * reshuffle relocated its file (possibly across two cycles, so the matching
+     * add isn't in THIS diff). When omitted, only the in-diff D+A/M coalescing
+     * applies.
+     */
+    currentPageIds?: Set<string>;
+}
+/**
+ * PURE push planner (SPEC §4/§6/§8). Classifies each diff row into a Docmost
+ * action by `pageId` identity, with NO IO (the `metaAt` resolver is injected).
+ *
+ * Classification rules:
+ *   - `A` (added):
+ *       - current meta HAS a pageId  -> UPDATE (a restored/copied file whose
+ *         page already exists; we push its content rather than create a dup).
+ *       - current meta has NO pageId but HAS a non-empty spaceId -> CREATE (a
+ *         brand-new local file; the page does not exist in Docmost yet).
+ *       - current meta has NO pageId and NO usable spaceId -> SKIP with reason
+ *         `create-without-spaceId`: Docmost `create_page` REQUIRES a spaceId
+ *         (§16), and a new local file may carry only partial human meta. We
+ *         refuse to create rather than guess a space (SPEC §8 guard spirit).
+ *   - `M` (modified): current meta has a pageId -> UPDATE content. (If a modified
+ *       file somehow lost its pageId it is skipped — there is nothing to target.)
+ *   - `D` (deleted): recover the pageId from the PRE-IMAGE meta (`metaAt(path,
+ *       'prev')`) -> DELETE. If no pageId can be recovered, SKIP with a reason
+ *       (untracked-file guard, SPEC §8: never delete an untracked page).
+ *   - `R` (renamed/moved): same pageId (from current meta), path changed ->
+ *       RENAME/MOVE. Resolution of move-vs-rename + the new parentPageId is
+ *       DEFERRED to the next increment; here we only record oldPath/newPath/
+ *       pageId. If the renamed file has no recoverable pageId it is SKIPPED.
+ *       (`C` copy is treated the same as `R` for recording purposes.)
+ */
+export declare function computePushActions(input: PushActionsInput): PushActions;
+/** The marker the push direction advances after a successful push (SPEC §5/§6). */
+export declare const LAST_PUSHED_REF = "refs/docmost/last-pushed";
+/**
+ * The mirror branch fast-forwarded after a clean push (SPEC §5/§6 step 3). It
+ * reflects "what Docmost currently contains"; advancing it to the pushed `main`
+ * commit closes the loop so the next pull diffs empty for the pushed pages.
+ */
+export declare const DOCMOST_BRANCH = "docmost";
+/**
+ * Injectable IO for `applyPushActions`. The real `main` (NEXT increment) wires
+ * these to the live client, `node:fs/promises`, and the vault git wrapper; this
+ * increment drives them only through FAKES in tests (no live destructive run).
+ *   - `client`: the create/update/delete/move/rename subset of `GitSyncClient`.
+ *   - `readFile`/`writeFile`: read a changed file's body / write a file back
+ *     (by vault-relative path; the applier does not resolve absolute paths so
+ *     fakes stay trivial).
+ *   - `git`: `updateRef` (advance `refs/docmost/last-pushed`) and
+ *     `fastForwardBranch` (advance the `docmost` mirror after a clean push, the
+ *     loop-close — SPEC §6 step 3 / §10).
+ */
+export interface ApplyPushDeps {
+    client: Pick<GitSyncClient, "importPageMarkdown" | "createPage" | "deletePage" | "movePage" | "renamePage">;
+    /** Read a changed file's full text by its vault-relative path. */
+    readFile: (path: string) => Promise<string>;
+    /** Write a file's full text by its vault-relative path. */
+    writeFile: (path: string, text: string) => Promise<void>;
+    /**
+     * The Docmost spaceId this vault mirrors. A CREATE targets this space (the
+     * native file carries no spaceId — every file in the vault belongs to it), and
+     * it backs the synthetic native meta the classifier reads.
+     */
+    spaceId: string;
+    /**
+     * `updateRef` advances `refs/docmost/last-pushed`; `fastForwardBranch` advances
+     * the `docmost` mirror after a clean push. `showFileAtRef` reads a file's text
+     * at a ref (used by the move/rename classifier to resolve the PREVIOUS parent
+     * folder's `.md` at `refs/docmost/last-pushed`, SPEC §5 path-as-truth).
+     */
+    git: Pick<VaultGit, "updateRef" | "fastForwardBranch" | "showFileAtRef">;
+}
+/** A file whose meta was rewritten with a freshly-assigned pageId (post-create). */
+export interface WrittenBackPage {
+    path: string;
+    pageId: string;
+}
+/**
+ * The per-page push record consulted by a FUTURE poll-suppression (SPEC §10): a
+ * pulled page whose body hash + `updatedAt` match a record here is OUR OWN write
+ * and must not be re-pulled. PRODUCED here; CONSUMED on the pull side later.
+ */
+export interface PushedPageRecord {
+    /** The Docmost pageId that was updated/created. */
+    pageId: string;
+    /**
+     * The `updatedAt` from the create/update client result, when the result
+     * exposed one. Absent when the (fake) client did not return it.
+     */
+    updatedAt?: string;
+    /** Stable hash of the markdown BODY that was pushed (SPEC §10 "хэш тела"). */
+    bodyHash: string;
+}
+/**
+ * One page whose operation FAILED during apply (SPEC §12 resumability). The bad
+ * page is isolated — recorded here — and the rest of the batch still runs; the
+ * refs are NOT advanced when there is any failure, so a re-run retries cleanly.
+ */
+export interface PushFailure {
+    kind: "update" | "create" | "delete" | "move" | "rename";
+    /** The pageId for update/delete/move/rename; absent for a never-id'd create. */
+    pageId?: string;
+    /** The vault-relative path for create/update/move/rename; absent for delete. */
+    path?: string;
+    /** The error message captured from the thrown error. */
+    error: string;
+}
+/**
+ * A rename/move action that resolved to a NO-OP (push #3, SPEC §5): a purely
+ * LOCAL file-path rename whose resolved parent AND title are both unchanged. The
+ * page identity is its pageId and the path is COSMETIC/local-only, so Docmost is
+ * NOT called — the skip is recorded here (with the reason) for logging.
+ */
+export interface PushNoop {
+    pageId: string;
+    oldPath: string;
+    newPath: string;
+    /** Why no Docmost op was emitted (currently always a path-only rename). */
+    reason: "path-only-rename";
+}
+/** Structured outcome of `applyPushActions` (counts + write-backs + noops). */
+export interface ApplyPushResult {
+    created: number;
+    updated: number;
+    deleted: number;
+    /** Pages reparented in Docmost via `move_page` (push #3, SPEC §5/§16). */
+    moved: number;
+    /** Pages retitled in Docmost via `rename_page` (push #3, SPEC §5/§6). */
+    renamed: number;
+    /**
+     * Files whose `gitmost_id` frontmatter was written with the pageId Docmost assigned on
+     * create — these now need a FOLLOW-UP commit (the meta on disk changed). The
+     * commit itself is the caller's job (NEXT increment); recorded here so it is
+     * not lost.
+     */
+    writtenBack: WrittenBackPage[];
+    /**
+     * Per-page push records (pageId + optional `updatedAt` + body hash) for every
+     * page successfully updated/created — the §10 loop-guard data a future
+     * poll-suppression (pull side) will consult so it does not re-pull our own
+     * write. Deletes are not included (no body was pushed).
+     */
+    pushed: PushedPageRecord[];
+    /**
+     * Pages whose operation threw — isolated and recorded, the batch continued
+     * (SPEC §12). Non-empty here means the refs were NOT advanced.
+     */
+    failures: PushFailure[];
+    /**
+     * Rename/move actions that resolved to a NO-OP — a purely LOCAL file-path
+     * rename (same parent, same title). NO Docmost call was made for these (SPEC
+     * §5: the page is its pageId, the path is local-only). Recorded for logging.
+     */
+    noops: PushNoop[];
+    /** Diff rows the planner could not classify (carried through for logging). */
+    skipped: PushActions["skipped"];
+    /** Whether `refs/docmost/last-pushed` was advanced (only on a CLEAN push). */
+    lastPushedAdvanced: boolean;
+    /**
+     * Result of fast-forwarding the `docmost` mirror branch after a CLEAN push
+     * (the loop-close, SPEC §6 step 3 / §10). `null` when no advance was attempted
+     * (no `pushedCommit`, or there were failures). `{ ok:false, reason }` when a
+     * non-fast-forward was REFUSED (divergent `docmost` history is never clobbered).
+     */
+    docmostFastForward: {
+        ok: boolean;
+        reason?: string;
+    } | null;
+}
+/**
+ * THIN IO applier for the COMMON push cases (create/update/delete). Exercised
+ * via FAKES only in this increment — there is no live wiring.
+ *
+ *   - UPDATE: read the file body, then `client.importPageMarkdown(pageId, body)`.
+ *     This is the collab/Yjs write path (SPEC §2/§15.6) — NEVER a raw jsonb
+ *     overwrite. The full self-contained markdown (meta + body) is sent as-is;
+ *     `importPageMarkdown` parses the meta/body itself.
+ *   - CREATE: derive title/spaceId/parentPageId from the file's current meta,
+ *     `client.createPage(...)`, take the assigned pageId from the result, and
+ *     write it BACK as the file's `gitmost_id` frontmatter (re-serialized via
+ *     `serializePageFile`, body preserved) so the file becomes
+ *     tracked. The write-back is recorded in `writtenBack` (a follow-up commit
+ *     is needed — NEXT increment).
+ *   - DELETE: `client.deletePage(pageId)` — soft-delete to Trash (SPEC §8).
+ *   - RENAME/MOVE (push #3, SPEC §5/§6/§16): classify each `renamesMoves` entry
+ *     with `classifyRenameMoves` (resolvers read the parent FOLDER's `.md` for
+ *     the parent pageId — path-as-truth — and the meta for the title), then:
+ *       - `move`   -> `client.movePage(pageId, parentPageId, position?)` (reparent;
+ *         `position` is UNDEFINED for now — the client supplies a default),
+ *       - `rename` -> `client.renamePage(pageId, title)` (title-only),
+ *       - BOTH     -> move (reparent) THEN rename (title), in that order,
+ *       - `noop`   -> NO client call; recorded in `noops` (a cosmetic local-only
+ *         file-path rename: the page is its pageId, the path is local, SPEC §5).
+ *
+ * FAIL-SAFE / per-page isolation (SPEC §12 resumability). Each page's operation
+ * is wrapped in its own try/catch: a single failing page is recorded in
+ * `failures[]` (with its kind + pageId/path + error) and the batch CONTINUES —
+ * one bad page must never block the rest. Crucially, the refs are advanced ONLY
+ * when `failures.length === 0`: a PARTIAL push must NOT advance
+ * `refs/docmost/last-pushed` or the `docmost` mirror, so a re-run retries the
+ * whole batch cleanly (the already-applied pages are idempotent re-applies).
+ *
+ * LOOP-CLOSE (SPEC §6 step 3 / §10). After a fully-successful push, when a
+ * `pushedCommit` is supplied:
+ *   - advance `refs/docmost/last-pushed` to it (what of `main` is in Docmost), AND
+ *   - fast-forward the `docmost` mirror branch to it via
+ *     `git.fastForwardBranch('docmost', pushedCommit)` — so the mirror reflects
+ *     what Docmost now contains and the NEXT pull diffs EMPTY for these pages
+ *     (it does not re-pull our own write). The ff is REFUSED (not forced) if
+ *     `docmost` is not an ancestor of the pushed commit; the result is surfaced
+ *     in `docmostFastForward`. On ANY failure, NEITHER ref is advanced.
+ *
+ * LOOP-GUARD DATA (SPEC §10). For every page successfully updated/created the
+ * result carries a `pushed` record `{ pageId, updatedAt?, bodyHash }` — the body
+ * hash of what was pushed plus the write's `updatedAt` (when the client returned
+ * one). A future pull-side poll-suppression consults this so it does not re-pull
+ * our own write; producing it is in scope here, consuming it is deferred.
+ *
+ * @param pushedCommit The `main` commit just reflected into Docmost (SHA or
+ *   commit-ish). When omitted, NEITHER ref is advanced (e.g. a dry plan).
+ */
+export declare function applyPushActions(deps: ApplyPushDeps, actions: PushActions, pushedCommit?: string): Promise<ApplyPushResult>;
+/**
+ * SPEC §5 path-as-truth: the parent FOLDER's `.md` file for a vault-relative
+ * (forward-slash) path. `buildVaultLayout` puts a page with children at
+ * `<...>/Title.md` and nests its children under `<...>/Title/`, so for
+ * `newPath = <dir>/Child.md` the parent page's file is `<dir>.md` (the enclosing
+ * folder, one level up). A path with NO enclosing folder (`Child.md`, at the
+ * space root) has no parent folder file -> `null` (the parent is ROOT).
+ */
+export declare function parentFolderFile(path: string): string | null;
+/**
+ * Whether a vault path is a Docmost PAGE file (design §"Адопция"): a `.md` file
+ * with NO dot-segment anywhere in its path. This excludes `.obsidian/` config,
+ * `.trash/`, dotfiles (`.foo.md`), and every non-`.md` file (attachments, JSON,
+ * …) — Obsidian owns those; they live in the vault but are never pages. Used to
+ * screen the PUSH diff so non-page files are never created/updated/deleted in
+ * Docmost (and never get a `gitmost_id` frontmatter written into them).
+ */
+export declare function isPageFile(path: string): boolean;
+/**
+ * The human ("local") git identity used for engine-made commits on `main` in the
+ * push direction (SPEC §7.3). The provenance is carried by the trailer (below),
+ * which the loop-guard keys on; the identity is for history readability only.
+ * When the vault repo already has a configured `user.name`/`user.email`, git
+ * uses that for the working-tree commit; this is the fallback the daemon stamps.
+ */
+export declare const LOCAL_AUTHOR_NAME = "Local";
+export declare const LOCAL_AUTHOR_EMAIL = "local@local";
+/** The provenance trailer marking a `main`-side (human/local) commit (SPEC §7.3). */
+export declare const LOCAL_SOURCE_TRAILER = "Docmost-Sync-Source: local";
+/**
+ * Injectable deps for `runPush` (mirrors `pull.ts`'s wiring; everything that
+ * touches the outside world is here so tests pass fakes). `makeClient` is a
+ * FACTORY, not a client — a dry-run must build NO client at all (it is never
+ * called), and only `--apply` invokes it.
+ */
+export interface PushDeps {
+    settings: Settings;
+    git: Pick<VaultGit, "assertGitAvailable" | "ensureRepo" | "isMergeInProgress" | "checkout" | "stageAll" | "commit" | "readRef" | "revParse" | "diffNameStatus" | "showFileAtRef" | "updateRef" | "fastForwardBranch" | "listTrackedFiles">;
+    /** Build a real client — called ONLY on `--apply`, never on dry-run. */
+    makeClient: (settings: Settings) => ApplyPushDeps["client"];
+    /** Read a file's full text by its vault-relative (forward-slash) path. */
+    readFile: (path: string) => Promise<string>;
+    /** Write a file's full text by its vault-relative path. */
+    writeFile: (path: string, text: string) => Promise<void>;
+    /** Structured logger (defaults to console in `main`; a recorder in tests). */
+    log: (line: string) => void;
+}
+/** The structured outcome of a `runPush` cycle (returned + summarized). */
+export interface PushRunResult {
+    /** Which path ran: `dry-run` (plan only) or `apply` (Docmost mutated). */
+    mode: "dry-run" | "apply";
+    /** Why the cycle stopped before planning, if it did (e.g. a left-over merge). */
+    aborted?: "merge-in-progress";
+    /** The diff base the plan was computed against (`last-pushed` else `docmost`). */
+    base?: {
+        ref: string;
+        source: "last-pushed" | "docmost";
+        sha: string | null;
+    };
+    /** The `main` commit the plan targets (the would-be pushed commit). */
+    pushedCommit?: string;
+    /** Planned action counts from the PURE planner (present once a plan was built). */
+    planned?: {
+        creates: number;
+        updates: number;
+        deletes: number;
+        renamesMoves: number;
+        skipped: number;
+    };
+    /** The applier's structured result — ONLY present on the `--apply` path. */
+    applied?: ApplyPushResult;
+    /**
+     * True when `applyPushActions` REFUSED to fast-forward a divergent `docmost`
+     * mirror (SPEC §5 invariant broken). Escalated (logged prominently) and folded
+     * into the CLI's non-zero exit.
+     */
+    divergentDocmost?: boolean;
+    /** Per-page failures from the applier (empty/absent on a clean run). */
+    failures?: PushFailure[];
+}
+/**
+ * Run one FS->Docmost push cycle (SPEC §6 "ФС → Docmost"), DRY-RUN BY DEFAULT.
+ *
+ * Steps (mirrors `pull.ts`):
+ *   1. Preflight git: `assertGitAvailable` + `ensureRepo`; ABORT (clear message +
+ *      non-zero-ish result) if a merge is in progress — never push on top of an
+ *      unresolved conflict (SPEC §9/§12). Conflict markers must NEVER reach
+ *      Docmost (SPEC §9).
+ *   2. Checkout `main` (the human-facing branch the push reads from).
+ *   3. Commit the human's pending working-tree changes on `main` with the
+ *      `local` provenance trailer (SPEC §7.3). A no-op when nothing changed.
+ *   4. Pick the diff BASE: `refs/docmost/last-pushed` if it resolves, else the
+ *      `docmost` mirror branch (what Docmost currently has). Resolve `main`.
+ *   5. `diffNameStatus(base, main)` -> changes; build the `metaAt(path, side)`
+ *      resolver (current = working tree, prev = `git show <base>:<path>`); run
+ *      the PURE `computePushActions`.
+ *   6. DRY-RUN (default): LOG the full plan and RETURN — NO client, NO Docmost
+ *      calls, NO ref advance.
+ *   7. `--apply`: build the client, run `applyPushActions(..., pushedCommit=main)`,
+ *      then (a) if any pageIds were written back (creates), commit them on `main`
+ *      with the `local` trailer and RE-advance `refs/docmost/last-pushed` to the
+ *      new commit so the recorded pageIds are persisted in what Docmost mirrors;
+ *      (b) ESCALATE a divergent-`docmost` ff refusal (SPEC §5) with a prominent
+ *      WARNING and a non-zero-ish flag. Then log a one-line summary.
+ */
+export declare function runPush(deps: PushDeps, opts: {
+    dryRun: boolean;
+}): Promise<PushRunResult>;
+/** Parsed `push` CLI flags. DRY-RUN is the default; `--apply` opts into writes. */
+export interface PushParsedArgs {
+    /** True when `--apply` was passed (the ONLY path that writes to Docmost). */
+    apply: boolean;
+}
+/**
+ * Parse the `push` CLI flags. SAFE BY DEFAULT: without `--apply` the run is a
+ * DRY-RUN (plan only). Exported so the flag handling is unit-testable.
+ */
+export declare function parseArgs(argv: string[]): PushParsedArgs;

packages/git-sync/build/engine/push.js

@@ -0,0 +1,971 @@
+import { parsePageFile, serializePageFile } from "../lib/page-file.js";
+import { DEFAULT_BRANCH } from "./git.js";
+import { bodyHash } from "./loop-guard.js";
+/**
+ * PURE classifier for the `renamesMoves` produced by `computePushActions`
+ * (push #3, SPEC §5/§6/§8). Resolves each `{pageId, oldPath, newPath}` into the
+ * Docmost op(s) it needs, with NO IO (both resolvers are injected).
+ *
+ * SPEC §5 — the file PATH is the source of truth for tree position, NOT the
+ * (possibly stale) `meta.parentPageId`. So the NEW parent is resolved from
+ * `newPath`'s enclosing folder, and the OLD parent from `oldPath`'s enclosing
+ * folder, via `deps.resolveParentPageId`. The title comes from the meta.
+ *
+ * For each entry:
+ *   - `newParent = resolveParentPageId(newPath, 'current')`,
+ *     `oldParent = resolveParentPageId(oldPath, 'prev')`.
+ *   - `newTitle = metaAt(newPath,'current')?.title`,
+ *     `oldTitle = metaAt(oldPath,'prev')?.title`.
+ *   - include `move` iff `newParent !== oldParent` (a real reparent),
+ *   - include `rename` iff `newTitle` is a NON-EMPTY string AND differs from
+ *     `oldTitle` (a real title edit; an empty/absent new title is never a rename),
+ *   - if NEITHER applies -> `noop: true` (a cosmetic local-only file-path rename;
+ *     the page is its pageId, so Docmost is not touched).
+ */
+export function classifyRenameMoves(renamesMoves, deps) {
+    return renamesMoves.map((rm) => {
+        const newParent = deps.resolveParentPageId(rm.newPath, "current");
+        const oldParent = deps.resolveParentPageId(rm.oldPath, "prev");
+        const newTitle = deps.metaAt(rm.newPath, "current")?.title;
+        const oldTitle = deps.metaAt(rm.oldPath, "prev")?.title;
+        const out = {
+            pageId: rm.pageId,
+            oldPath: rm.oldPath,
+            newPath: rm.newPath,
+        };
+        // A reparent: the new path's resolved parent page differs from the old's.
+        if (newParent !== oldParent) {
+            out.move = { parentPageId: newParent };
+        }
+        // A title edit: only when there is a real, non-empty new title that changed.
+        if (typeof newTitle === "string" &&
+            newTitle.length > 0 &&
+            newTitle !== oldTitle) {
+            out.rename = { title: newTitle };
+        }
+        // Neither changed -> a purely LOCAL file-path rename; do NOT call Docmost.
+        if (!out.move && !out.rename) {
+            out.noop = true;
+        }
+        return out;
+    });
+}
+/**
+ * PURE push planner (SPEC §4/§6/§8). Classifies each diff row into a Docmost
+ * action by `pageId` identity, with NO IO (the `metaAt` resolver is injected).
+ *
+ * Classification rules:
+ *   - `A` (added):
+ *       - current meta HAS a pageId  -> UPDATE (a restored/copied file whose
+ *         page already exists; we push its content rather than create a dup).
+ *       - current meta has NO pageId but HAS a non-empty spaceId -> CREATE (a
+ *         brand-new local file; the page does not exist in Docmost yet).
+ *       - current meta has NO pageId and NO usable spaceId -> SKIP with reason
+ *         `create-without-spaceId`: Docmost `create_page` REQUIRES a spaceId
+ *         (§16), and a new local file may carry only partial human meta. We
+ *         refuse to create rather than guess a space (SPEC §8 guard spirit).
+ *   - `M` (modified): current meta has a pageId -> UPDATE content. (If a modified
+ *       file somehow lost its pageId it is skipped — there is nothing to target.)
+ *   - `D` (deleted): recover the pageId from the PRE-IMAGE meta (`metaAt(path,
+ *       'prev')`) -> DELETE. If no pageId can be recovered, SKIP with a reason
+ *       (untracked-file guard, SPEC §8: never delete an untracked page).
+ *   - `R` (renamed/moved): same pageId (from current meta), path changed ->
+ *       RENAME/MOVE. Resolution of move-vs-rename + the new parentPageId is
+ *       DEFERRED to the next increment; here we only record oldPath/newPath/
+ *       pageId. If the renamed file has no recoverable pageId it is SKIPPED.
+ *       (`C` copy is treated the same as `R` for recording purposes.)
+ */
+export function computePushActions(input) {
+    const { metaAt, currentPageIds } = input;
+    // PAGE-FILE FILTER (design §"Адопция"): only `.md` files OUTSIDE any dot-folder
+    // are Docmost pages. `.obsidian/*`, attachments, and other non-page files are
+    // committed to the vault (no `.gitignore`) and so appear in the diff, but they
+    // are NEVER pages — Obsidian owns them. Without this filter every ADDED such
+    // file would be mis-classified as a CREATE (nativeMeta always supplies a
+    // spaceId, so the old `create-without-spaceId` skip no longer screens them),
+    // creating junk pages in Docmost and corrupting the file with a `gitmost_id`
+    // frontmatter. Filter BEFORE any classification so non-page A/M/D/R are ignored.
+    const changes = input.changes.filter((c) => isPageFile(c.path));
+    const actions = {
+        creates: [],
+        updates: [],
+        deletes: [],
+        renamesMoves: [],
+        skipped: [],
+    };
+    // GHOST-MOVE coalescing (⭐ data-loss guard). git's rename detection (`-M`)
+    // can miss a move when the two files are too dissimilar — which is exactly the
+    // case for the tiny meta-only files a layout RESHUFFLE produces (e.g.
+    // several untitled pages sharing the `_` fallback name; retitling one frees the
+    // bare `_` and another page's file relocates `_ ~slug.md` -> `_.md`). git then
+    // reports the move as a DELETE of the old path + an ADD of the new one. Taken
+    // literally that soft-deletes a page that merely MOVED — a live page vanishing
+    // into Trash. Identity is the pageId, not git's heuristic: a pageId that is
+    // BOTH deleted (pre-image) and added (current) is one page that relocated, so
+    // we classify it as a rename/move and NEVER as a delete.
+    // A pageId can land at its new path two ways: as an ADD (the path was free) or
+    // as a MODIFY (the path was occupied by ANOTHER page that left — the reshuffle
+    // case, where `_.md`'s occupant changes pageId). Both are "the page survives at
+    // a new path", so the surviving side is the CURRENT-meta pageId of A *and* M.
+    const deletedPath = new Map();
+    const survivingPath = new Map();
+    for (const change of changes) {
+        if (change.status === "D") {
+            const pid = metaAt(change.path, "prev")?.pageId;
+            if (pid)
+                deletedPath.set(pid, change.path);
+        }
+        else if (change.status === "A" || change.status === "M") {
+            const pid = metaAt(change.path, "current")?.pageId;
+            if (pid)
+                survivingPath.set(pid, change.path);
+        }
+    }
+    const ghostMove = new Map();
+    for (const [pid, oldPath] of deletedPath) {
+        const newPath = survivingPath.get(pid);
+        if (newPath && newPath !== oldPath) {
+            ghostMove.set(pid, { oldPath, newPath });
+        }
+    }
+    for (const change of changes) {
+        switch (change.status) {
+            case "A": {
+                const meta = metaAt(change.path, "current");
+                const pageId = meta?.pageId;
+                if (pageId && ghostMove.has(pageId)) {
+                    // Half of a git-undetected move (a matching DELETE exists): record it
+                    // as a rename/move (like a real `R`), NOT an update — the `D` side is
+                    // suppressed so the page is never soft-deleted.
+                    actions.renamesMoves.push({
+                        pageId,
+                        oldPath: ghostMove.get(pageId).oldPath,
+                        newPath: change.path,
+                    });
+                }
+                else if (pageId) {
+                    // Added but already carries a pageId (restored/copied file): the page
+                    // exists in Docmost, so push content as an UPDATE — never a duplicate.
+                    actions.updates.push({ pageId, path: change.path });
+                }
+                else if (meta?.spaceId) {
+                    // Brand-new local file with a target space -> create the page, then
+                    // write the assigned pageId back into its meta (in `applyPushActions`).
+                    // `meta.spaceId` is truthy here, so empty-string is also rejected.
+                    actions.creates.push({ path: change.path });
+                }
+                else {
+                    // A create needs a spaceId (Docmost `create_page` requires it, §16). A
+                    // new file with partial meta and no usable spaceId is SKIPPED rather
+                    // than created into a guessed space (SPEC §8 guard spirit).
+                    actions.skipped.push({
+                        path: change.path,
+                        status: "A",
+                        reason: "create-without-spaceId",
+                    });
+                }
+                break;
+            }
+            case "M": {
+                const meta = metaAt(change.path, "current");
+                const pageId = meta?.pageId;
+                if (pageId && ghostMove.has(pageId)) {
+                    // This path's occupant changed pageId: the previous page left and THIS
+                    // page relocated here (a reshuffle). Its old file was DELETED elsewhere
+                    // — coalesce into a rename/move so the page is never trashed.
+                    actions.renamesMoves.push({
+                        pageId,
+                        oldPath: ghostMove.get(pageId).oldPath,
+                        newPath: change.path,
+                    });
+                }
+                else if (pageId) {
+                    actions.updates.push({ pageId, path: change.path });
+                }
+                else {
+                    // A modified file with no pageId has no Docmost target to update.
+                    actions.skipped.push({
+                        path: change.path,
+                        status: "M",
+                        reason: "modified file has no pageId in meta",
+                    });
+                }
+                break;
+            }
+            case "D": {
+                // The file is gone from `main`; recover its pageId from the PRE-IMAGE
+                // (the version last pushed to Docmost) so we delete the RIGHT page.
+                const prevMeta = metaAt(change.path, "prev");
+                const pageId = prevMeta?.pageId;
+                if (pageId && ghostMove.has(pageId)) {
+                    // The same pageId was re-ADDED at a new path: this is a git-undetected
+                    // MOVE, handled by the `A` branch above. Suppress the delete so a moved
+                    // page is never trashed (⭐ data-loss guard).
+                    actions.skipped.push({
+                        path: change.path,
+                        status: "D",
+                        reason: "ghost-move (re-added at a new path) — not a deletion",
+                    });
+                }
+                else if (pageId && currentPageIds?.has(pageId)) {
+                    // The pageId still EXISTS elsewhere in the current tree: the file moved
+                    // (a layout reshuffle whose matching add was in an earlier cycle, so it
+                    // is not in this diff). A live page must never be trashed because its
+                    // FILENAME changed — identity is the pageId (⭐ data-loss guard).
+                    actions.skipped.push({
+                        path: change.path,
+                        status: "D",
+                        reason: "pageId still present in the tree (moved) — not a deletion",
+                    });
+                }
+                else if (pageId) {
+                    actions.deletes.push({ pageId });
+                }
+                else {
+                    // Untracked-file guard (SPEC §8): a file with no recoverable pageId was
+                    // never a Docmost page — do NOT translate its removal into a delete.
+                    actions.skipped.push({
+                        path: change.path,
+                        status: "D",
+                        reason: "deleted file has no recoverable pageId (pre-image meta)",
+                    });
+                }
+                break;
+            }
+            case "R":
+            case "C": {
+                // Same page, new path. Identity comes from the CURRENT (post-rename) meta
+                // since the file still exists. RESOLUTION (move vs rename, parentPageId)
+                // is deferred — record oldPath/newPath/pageId only.
+                const meta = metaAt(change.path, "current");
+                const pageId = meta?.pageId;
+                const oldPath = change.oldPath ?? change.path;
+                if (pageId) {
+                    actions.renamesMoves.push({
+                        pageId,
+                        oldPath,
+                        newPath: change.path,
+                    });
+                }
+                else {
+                    actions.skipped.push({
+                        path: change.path,
+                        status: change.status,
+                        reason: "renamed/moved file has no pageId in meta",
+                    });
+                }
+                break;
+            }
+            default: {
+                // Unreachable for A/M/D/R/C; defensive for any future status.
+                actions.skipped.push({
+                    path: change.path,
+                    status: change.status,
+                    reason: `unhandled diff status ${change.status}`,
+                });
+            }
+        }
+    }
+    return actions;
+}
+// --- thin apply (create/update/delete), fakes-only in this increment ---------
+/** The marker the push direction advances after a successful push (SPEC §5/§6). */
+export const LAST_PUSHED_REF = "refs/docmost/last-pushed";
+/**
+ * The mirror branch fast-forwarded after a clean push (SPEC §5/§6 step 3). It
+ * reflects "what Docmost currently contains"; advancing it to the pushed `main`
+ * commit closes the loop so the next pull diffs empty for the pushed pages.
+ */
+export const DOCMOST_BRANCH = "docmost";
+/**
+ * THIN IO applier for the COMMON push cases (create/update/delete). Exercised
+ * via FAKES only in this increment — there is no live wiring.
+ *
+ *   - UPDATE: read the file body, then `client.importPageMarkdown(pageId, body)`.
+ *     This is the collab/Yjs write path (SPEC §2/§15.6) — NEVER a raw jsonb
+ *     overwrite. The full self-contained markdown (meta + body) is sent as-is;
+ *     `importPageMarkdown` parses the meta/body itself.
+ *   - CREATE: derive title/spaceId/parentPageId from the file's current meta,
+ *     `client.createPage(...)`, take the assigned pageId from the result, and
+ *     write it BACK as the file's `gitmost_id` frontmatter (re-serialized via
+ *     `serializePageFile`, body preserved) so the file becomes
+ *     tracked. The write-back is recorded in `writtenBack` (a follow-up commit
+ *     is needed — NEXT increment).
+ *   - DELETE: `client.deletePage(pageId)` — soft-delete to Trash (SPEC §8).
+ *   - RENAME/MOVE (push #3, SPEC §5/§6/§16): classify each `renamesMoves` entry
+ *     with `classifyRenameMoves` (resolvers read the parent FOLDER's `.md` for
+ *     the parent pageId — path-as-truth — and the meta for the title), then:
+ *       - `move`   -> `client.movePage(pageId, parentPageId, position?)` (reparent;
+ *         `position` is UNDEFINED for now — the client supplies a default),
+ *       - `rename` -> `client.renamePage(pageId, title)` (title-only),
+ *       - BOTH     -> move (reparent) THEN rename (title), in that order,
+ *       - `noop`   -> NO client call; recorded in `noops` (a cosmetic local-only
+ *         file-path rename: the page is its pageId, the path is local, SPEC §5).
+ *
+ * FAIL-SAFE / per-page isolation (SPEC §12 resumability). Each page's operation
+ * is wrapped in its own try/catch: a single failing page is recorded in
+ * `failures[]` (with its kind + pageId/path + error) and the batch CONTINUES —
+ * one bad page must never block the rest. Crucially, the refs are advanced ONLY
+ * when `failures.length === 0`: a PARTIAL push must NOT advance
+ * `refs/docmost/last-pushed` or the `docmost` mirror, so a re-run retries the
+ * whole batch cleanly (the already-applied pages are idempotent re-applies).
+ *
+ * LOOP-CLOSE (SPEC §6 step 3 / §10). After a fully-successful push, when a
+ * `pushedCommit` is supplied:
+ *   - advance `refs/docmost/last-pushed` to it (what of `main` is in Docmost), AND
+ *   - fast-forward the `docmost` mirror branch to it via
+ *     `git.fastForwardBranch('docmost', pushedCommit)` — so the mirror reflects
+ *     what Docmost now contains and the NEXT pull diffs EMPTY for these pages
+ *     (it does not re-pull our own write). The ff is REFUSED (not forced) if
+ *     `docmost` is not an ancestor of the pushed commit; the result is surfaced
+ *     in `docmostFastForward`. On ANY failure, NEITHER ref is advanced.
+ *
+ * LOOP-GUARD DATA (SPEC §10). For every page successfully updated/created the
+ * result carries a `pushed` record `{ pageId, updatedAt?, bodyHash }` — the body
+ * hash of what was pushed plus the write's `updatedAt` (when the client returned
+ * one). A future pull-side poll-suppression consults this so it does not re-pull
+ * our own write; producing it is in scope here, consuming it is deferred.
+ *
+ * @param pushedCommit The `main` commit just reflected into Docmost (SHA or
+ *   commit-ish). When omitted, NEITHER ref is advanced (e.g. a dry plan).
+ */
+export async function applyPushActions(deps, actions, pushedCommit) {
+    const { client, git } = deps;
+    let created = 0;
+    let updated = 0;
+    let deleted = 0;
+    let moved = 0;
+    let renamed = 0;
+    const writtenBack = [];
+    const pushed = [];
+    const failures = [];
+    const noops = [];
+    // 1. UPDATES — collab/Yjs write path (SPEC §2/§15.6), never a raw overwrite.
+    //    Each update is isolated: a thrown page is recorded and the batch goes on.
+    for (const u of actions.updates) {
+        try {
+            // Push the CLEAN body only (no `gitmost_id` frontmatter): the frontmatter
+            // is engine metadata, never page content. The server converts the markdown
+            // it receives verbatim, so stripping here keeps the id out of Docmost.
+            const body = parsePageFile(await deps.readFile(u.path)).body;
+            // The last-synced version of this file (pre-image) is the common ancestor
+            // for a 3-way merge against the live page, so concurrent human edits are
+            // not clobbered (review #5). Null when the file is new at last-pushed. Its
+            // body is stripped the SAME way so the merge compares body-to-body.
+            const baseFull = await deps.git.showFileAtRef(LAST_PUSHED_REF, u.path);
+            const baseMarkdown = baseFull === null ? null : parsePageFile(baseFull).body;
+            const result = await client.importPageMarkdown(u.pageId, body, baseMarkdown);
+            updated++;
+            // §10 loop-guard data: hash the BODY we pushed + capture `updatedAt`.
+            pushed.push({
+                pageId: u.pageId,
+                ...extractUpdatedAt(result),
+                bodyHash: bodyHash(body),
+            });
+        }
+        catch (err) {
+            failures.push({
+                kind: "update",
+                pageId: u.pageId,
+                path: u.path,
+                error: errMessage(err),
+            });
+        }
+    }
+    // 2. CREATES — create the page, then write the assigned pageId back to meta so
+    //    the file becomes tracked (SPEC §4 "записать присвоенный pageId обратно").
+    //    Isolated per page like updates.
+    for (const c of actions.creates) {
+        try {
+            const text = await deps.readFile(c.path);
+            const { body } = parsePageFile(text);
+            // Derive create args from the PATH (native-Obsidian, SPEC §5): title from
+            // the filename, parent from the enclosing folder's folder-note, space from
+            // the run (the vault's space). `parentPageId: null` -> created at ROOT.
+            const title = titleFromPath(c.path);
+            const parentPageId = (await resolveParentPageIdViaTree(deps, c.path, "current")) ?? undefined;
+            const result = await client.createPage(title, body, deps.spaceId, parentPageId);
+            // `createPage` returns `{ data: { id, ... }, success }`; the assigned
+            // pageId is at `result.data.id`.
+            const assignedPageId = result?.data?.id;
+            if (assignedPageId) {
+                // Write the assigned pageId back as the `gitmost_id` frontmatter, body
+                // preserved — the file becomes engine-tracked (SPEC §4).
+                const rewritten = serializePageFile(assignedPageId, body);
+                await deps.writeFile(c.path, rewritten);
+                writtenBack.push({ path: c.path, pageId: assignedPageId });
+                // §10 loop-guard data for the created page (hash the pushed BODY).
+                pushed.push({
+                    pageId: assignedPageId,
+                    ...extractUpdatedAt(result),
+                    bodyHash: bodyHash(body),
+                });
+            }
+            created++;
+        }
+        catch (err) {
+            failures.push({ kind: "create", path: c.path, error: errMessage(err) });
+        }
+    }
+    // 3. DELETES — soft-delete to Trash (SPEC §8), reversible. Isolated per page.
+    for (const d of actions.deletes) {
+        try {
+            await client.deletePage(d.pageId);
+            deleted++;
+        }
+        catch (err) {
+            failures.push({
+                kind: "delete",
+                pageId: d.pageId,
+                error: errMessage(err),
+            });
+        }
+    }
+    // 4. RENAME/MOVE (push #3, SPEC §5/§6/§16). Classify each entry against the
+    //    tree-backed resolvers (the NEW parent comes from the new path's enclosing
+    //    folder `.md`, the OLD parent from the old path's at last-pushed — PATH is
+    //    the truth, not stale `meta.parentPageId`; the title from the meta), then
+    //    apply only the real ops. Each page is isolated like the cases above: a
+    //    thrown op is recorded in `failures` and the batch continues. ORDER for a
+    //    page that needs both: reparent (move) FIRST, then retitle (rename).
+    if (actions.renamesMoves.length > 0) {
+        // The classifier is PURE over sync resolvers; the tree reads are async, so
+        // prefetch every (path, side) lookup it will make into plain tables first.
+        const parentTable = new Map();
+        const metaTable = new Map();
+        // A tree read (readFile / git.showFileAtRef) throwing must isolate THAT page
+        // into `failures`, NOT abort the whole batch (§12 resumability). The helpers
+        // already swallow their own errors, but this per-entry try/catch keeps the
+        // batch-isolation invariant holding regardless of future changes to them.
+        const prefetchFailed = new Set();
+        for (const rm of actions.renamesMoves) {
+            // newParent + newTitle from the CURRENT tree; oldParent + oldTitle from the
+            // last-pushed pre-image (`prev`). Keyed by `path|side` so duplicates fold.
+            try {
+                parentTable.set(`${rm.newPath}|current`, await resolveParentPageIdViaTree(deps, rm.newPath, "current"));
+                parentTable.set(`${rm.oldPath}|prev`, await resolveParentPageIdViaTree(deps, rm.oldPath, "prev"));
+                metaTable.set(`${rm.newPath}|current`, await metaAtViaTree(deps, rm.newPath, "current", deps.spaceId));
+                metaTable.set(`${rm.oldPath}|prev`, await metaAtViaTree(deps, rm.oldPath, "prev", deps.spaceId));
+            }
+            catch (err) {
+                prefetchFailed.add(rm.pageId);
+                failures.push({
+                    kind: "move",
+                    pageId: rm.pageId,
+                    path: rm.newPath,
+                    error: errMessage(err),
+                });
+            }
+        }
+        const classified = classifyRenameMoves(actions.renamesMoves.filter((rm) => !prefetchFailed.has(rm.pageId)), {
+            metaAt: (path, side) => metaTable.get(`${path}|${side}`) ?? null,
+            resolveParentPageId: (path, side) => parentTable.get(`${path}|${side}`) ?? null,
+        });
+        for (const c of classified) {
+            if (c.noop) {
+                // Cosmetic local-only file-path rename — no Docmost op (SPEC §5).
+                noops.push({
+                    pageId: c.pageId,
+                    oldPath: c.oldPath,
+                    newPath: c.newPath,
+                    reason: "path-only-rename",
+                });
+                continue;
+            }
+            // Track which op is in flight so a failure is attributed to the op that
+            // ACTUALLY threw: for a page needing both, a move that succeeds then a
+            // rename that throws must be recorded as `rename`, not `move`.
+            let failingKind = c.move ? "move" : "rename";
+            try {
+                // Reparent FIRST so the page is in its new tree position, THEN retitle.
+                if (c.move) {
+                    failingKind = "move";
+                    // TODO(next): compute a fractional-index position between siblings
+                    // (SPEC §16). `position` is UNDEFINED here; the client supplies a valid
+                    // default. Pass `parentPageId: null` for a move to the space ROOT.
+                    await client.movePage(c.pageId, c.move.parentPageId);
+                    moved++;
+                }
+                if (c.rename) {
+                    failingKind = "rename";
+                    await client.renamePage(c.pageId, c.rename.title);
+                    renamed++;
+                }
+            }
+            catch (err) {
+                // Isolate the failed page: the op that ACTUALLY threw is recorded so a
+                // re-run can retry. A move that threw before its rename leaves `rename`
+                // for the next run (idempotent re-apply); refs are NOT advanced (below).
+                failures.push({
+                    kind: failingKind,
+                    pageId: c.pageId,
+                    path: c.newPath,
+                    error: errMessage(err),
+                });
+            }
+        }
+    }
+    // 5. Advance the refs ONLY on a CLEAN push (no failures) AND when a pushed
+    //    commit is supplied. A partial push must advance NEITHER ref, so a re-run
+    //    retries the whole batch (SPEC §12). The loop-close (SPEC §6 step 3 / §10):
+    //    advance `refs/docmost/last-pushed` AND fast-forward the `docmost` mirror,
+    //    so Docmost's new content is mirrored and the next pull diffs empty.
+    let lastPushedAdvanced = false;
+    let docmostFastForward = null;
+    if (pushedCommit && failures.length === 0) {
+        await git.updateRef(LAST_PUSHED_REF, pushedCommit);
+        lastPushedAdvanced = true;
+        // Fast-forward the mirror (refused, not forced, on a non-fast-forward — the
+        // caller logs the reason). Surfaced in the result.
+        docmostFastForward = await git.fastForwardBranch(DOCMOST_BRANCH, pushedCommit);
+    }
+    return {
+        created,
+        updated,
+        deleted,
+        moved,
+        renamed,
+        writtenBack,
+        pushed,
+        failures,
+        noops,
+        skipped: actions.skipped,
+        lastPushedAdvanced,
+        docmostFastForward,
+    };
+}
+/** Stringify a thrown value into a stable error message. */
+function errMessage(err) {
+    return err instanceof Error ? err.message : String(err);
+}
+/**
+ * SPEC §5 path-as-truth: the parent FOLDER's `.md` file for a vault-relative
+ * (forward-slash) path. `buildVaultLayout` puts a page with children at
+ * `<...>/Title.md` and nests its children under `<...>/Title/`, so for
+ * `newPath = <dir>/Child.md` the parent page's file is `<dir>.md` (the enclosing
+ * folder, one level up). A path with NO enclosing folder (`Child.md`, at the
+ * space root) has no parent folder file -> `null` (the parent is ROOT).
+ */
+export function parentFolderFile(path) {
+    const slash = path.lastIndexOf("/");
+    if (slash < 0)
+        return null; // root-level file: parent is ROOT.
+    const dir = path.slice(0, slash); // the enclosing folder
+    // The page that OWNS the enclosing folder is its folder-note `<dir>/<base>.md`.
+    const folderNote = `${dir}/${baseSegment(dir)}.md`;
+    if (path === folderNote) {
+        // This path IS its folder's folder-note, so its parent is ONE LEVEL UP: the
+        // folder-note of the grandparent folder (or ROOT at the top level).
+        const up = dir.lastIndexOf("/");
+        if (up < 0)
+            return null; // top-level folder -> parent is ROOT.
+        const grandDir = dir.slice(0, up);
+        return `${grandDir}/${baseSegment(grandDir)}.md`;
+    }
+    // A leaf (or a nested folder-note) sitting inside `dir`: its parent is `dir`'s
+    // folder-note.
+    return folderNote;
+}
+/**
+ * Whether a vault path is a Docmost PAGE file (design §"Адопция"): a `.md` file
+ * with NO dot-segment anywhere in its path. This excludes `.obsidian/` config,
+ * `.trash/`, dotfiles (`.foo.md`), and every non-`.md` file (attachments, JSON,
+ * …) — Obsidian owns those; they live in the vault but are never pages. Used to
+ * screen the PUSH diff so non-page files are never created/updated/deleted in
+ * Docmost (and never get a `gitmost_id` frontmatter written into them).
+ */
+export function isPageFile(path) {
+    if (!path.endsWith(".md"))
+        return false;
+    return !path.split("/").some((seg) => seg.startsWith("."));
+}
+/** The last path segment of a forward-slash path (the folder/file base name). */
+function baseSegment(path) {
+    const slash = path.lastIndexOf("/");
+    return slash < 0 ? path : path.slice(slash + 1);
+}
+/**
+ * The page TITLE derived from a vault path: the file's base name without the
+ * `.md` extension. In the native-Obsidian layout the filename IS the title — for
+ * a folder-note `<dir>/<base>.md` that base equals the folder name, so the same
+ * rule yields the folder's title. Self-consistent across pull/push: a pulled
+ * (possibly disambiguated) filename round-trips to the same title, so a stable
+ * file never pushes a spurious rename.
+ */
+function titleFromPath(path) {
+    const base = baseSegment(path);
+    return base.endsWith(".md") ? base.slice(0, -3) : base;
+}
+/**
+ * Build the synthetic `DocmostMdMeta` the planner/classifier consume, from the
+ * NATIVE format: `pageId` from the `gitmost_id` frontmatter, `title` from the
+ * filename, `spaceId` from the run (the vault's space — every file belongs to
+ * it). `parentPageId` is intentionally absent: tree position is resolved from the
+ * PATH (`resolveParentPageId`), never from a stored field (SPEC §5).
+ */
+function nativeMeta(text, path, spaceId) {
+    const { id } = parsePageFile(text);
+    const meta = { version: 1, title: titleFromPath(path), spaceId };
+    if (id)
+        meta.pageId = id;
+    return meta;
+}
+/**
+ * Build the `resolveParentPageId(path, side)` resolver `classifyRenameMoves`
+ * needs, reading the PARENT FOLDER's `.md` (SPEC §5 path-as-truth):
+ *   - `current` -> `deps.readFile(<dir>.md)` (the live working tree),
+ *   - `prev`    -> `git.showFileAtRef('refs/docmost/last-pushed', <dir>.md)` (the
+ *     last-pushed pre-image),
+ * then read its `gitmost_id` frontmatter and return that page's pageId. A root-level path
+ * (no enclosing folder), a missing/unreadable parent file, or a parent file with
+ * no parseable pageId all resolve to `null` (parent is ROOT / unknown ->
+ * `parentPageId: null`, SPEC §16 "parentPageId: null -> в корень").
+ *
+ * The IO is async, so this returns an ASYNC resolver; the call sites prefetch the
+ * parent pageIds (the classifier itself stays pure/sync over a plain table).
+ */
+async function resolveParentPageIdViaTree(deps, path, side) {
+    const parentFile = parentFolderFile(path);
+    if (parentFile === null)
+        return null; // root-level: parent is ROOT.
+    let text;
+    try {
+        text =
+            side === "current"
+                ? await deps.readFile(parentFile)
+                : await deps.git.showFileAtRef(LAST_PUSHED_REF, parentFile);
+    }
+    catch {
+        // Parent folder file missing/unreadable at that side -> treat as ROOT.
+        return null;
+    }
+    if (text === null)
+        return null; // showFileAtRef returns null when absent.
+    // The parent page's identity is its `gitmost_id` frontmatter; folder position
+    // is irrelevant here, only the pageId.
+    return parsePageFile(text).id;
+}
+/**
+ * Resolve the synthetic native meta at a side for the rename/move classifier (the
+ * title — derived from the path — comes from here). Mirrors
+ * `resolveParentPageIdViaTree`'s IO sides: `current` reads the working tree,
+ * `prev` reads `refs/docmost/last-pushed`. Returns `null` only when the file is
+ * missing/unreadable at that side (a real absence the classifier must see).
+ */
+async function metaAtViaTree(deps, path, side, spaceId) {
+    let text;
+    try {
+        text =
+            side === "current"
+                ? await deps.readFile(path)
+                : await deps.git.showFileAtRef(LAST_PUSHED_REF, path);
+    }
+    catch {
+        return null;
+    }
+    if (text === null)
+        return null;
+    return nativeMeta(text, path, spaceId);
+}
+/**
+ * Pull an `updatedAt` out of a create/update client result, if present. The
+ * shape is `{ data: { updatedAt? }, ... }` (createPage) or a flatter object;
+ * absent in the simple fakes, so the field is omitted rather than `undefined`.
+ */
+function extractUpdatedAt(result) {
+    const r = result;
+    const raw = r?.data?.updatedAt ?? r?.updatedAt;
+    return typeof raw === "string" ? { updatedAt: raw } : {};
+}
+// --- runnable push orchestration (`runPush`) ---------------------------------
+//
+// `runPush` is the FS->Docmost twin of `pull.ts`'s `main`: it wires the VaultGit
+// diff/ref primitives + the PURE `computePushActions` planner + the THIN
+// `applyPushActions` applier into one runnable cycle. SAFE BY DEFAULT — the
+// engine's FIRST write path to Docmost defaults to DRY-RUN (plan only, NO
+// Docmost writes, NO ref advance); an explicit `--apply` is the ONLY path that
+// builds a client and mutates Docmost.
+//
+// Every external effect is injected (`PushDeps`) so the whole orchestration is
+// driven by FAKES in tests — no live Docmost, git, fs, or network.
+/**
+ * The human ("local") git identity used for engine-made commits on `main` in the
+ * push direction (SPEC §7.3). The provenance is carried by the trailer (below),
+ * which the loop-guard keys on; the identity is for history readability only.
+ * When the vault repo already has a configured `user.name`/`user.email`, git
+ * uses that for the working-tree commit; this is the fallback the daemon stamps.
+ */
+export const LOCAL_AUTHOR_NAME = "Local";
+export const LOCAL_AUTHOR_EMAIL = "local@local";
+/** The provenance trailer marking a `main`-side (human/local) commit (SPEC §7.3). */
+export const LOCAL_SOURCE_TRAILER = "Docmost-Sync-Source: local";
+/**
+ * Run one FS->Docmost push cycle (SPEC §6 "ФС → Docmost"), DRY-RUN BY DEFAULT.
+ *
+ * Steps (mirrors `pull.ts`):
+ *   1. Preflight git: `assertGitAvailable` + `ensureRepo`; ABORT (clear message +
+ *      non-zero-ish result) if a merge is in progress — never push on top of an
+ *      unresolved conflict (SPEC §9/§12). Conflict markers must NEVER reach
+ *      Docmost (SPEC §9).
+ *   2. Checkout `main` (the human-facing branch the push reads from).
+ *   3. Commit the human's pending working-tree changes on `main` with the
+ *      `local` provenance trailer (SPEC §7.3). A no-op when nothing changed.
+ *   4. Pick the diff BASE: `refs/docmost/last-pushed` if it resolves, else the
+ *      `docmost` mirror branch (what Docmost currently has). Resolve `main`.
+ *   5. `diffNameStatus(base, main)` -> changes; build the `metaAt(path, side)`
+ *      resolver (current = working tree, prev = `git show <base>:<path>`); run
+ *      the PURE `computePushActions`.
+ *   6. DRY-RUN (default): LOG the full plan and RETURN — NO client, NO Docmost
+ *      calls, NO ref advance.
+ *   7. `--apply`: build the client, run `applyPushActions(..., pushedCommit=main)`,
+ *      then (a) if any pageIds were written back (creates), commit them on `main`
+ *      with the `local` trailer and RE-advance `refs/docmost/last-pushed` to the
+ *      new commit so the recorded pageIds are persisted in what Docmost mirrors;
+ *      (b) ESCALATE a divergent-`docmost` ff refusal (SPEC §5) with a prominent
+ *      WARNING and a non-zero-ish flag. Then log a one-line summary.
+ */
+export async function runPush(deps, opts) {
+    const { git, settings, log } = deps;
+    const dryRun = opts.dryRun;
+    // 1. Preflight git. Fail fast (actionable message via main().catch) if the git
+    //    binary is missing — the vault state store relies on it.
+    await git.assertGitAvailable();
+    await git.ensureRepo();
+    // 1b. Refuse to push on top of an unresolved merge (SPEC §9/§12). A previous
+    //     conflicting pull leaves the vault mid-merge; pushing now could leak
+    //     conflict markers into Docmost (SPEC §9, the cardinal invariant). Detect
+    //     it BEFORE any checkout/diff and stop with a clear, actionable message so
+    //     re-runs converge once the human resolves (or aborts) the merge.
+    if (await git.isMergeInProgress()) {
+        log(`push: vault has an unresolved merge at ${settings.vaultPath} — resolve ` +
+            `it (or 'git merge --abort') and re-run. Nothing was pushed to Docmost ` +
+            `(conflict markers must never reach Docmost, SPEC §9).`);
+        return { mode: dryRun ? "dry-run" : "apply", aborted: "merge-in-progress" };
+    }
+    // 2. Work on `main` — the human-facing branch the push diffs FROM.
+    await git.checkout(DEFAULT_BRANCH);
+    // 3. Commit the human's pending working-tree changes on `main` with the `local`
+    //    provenance trailer (SPEC §7.3). A no-op commit when nothing changed is
+    //    fine (`commit` returns false). The loop-guard keys on the trailer.
+    //    Even on a "plan only" dry-run this commits the working tree (it is the
+    //    only way to diff `base..main`, acceptable §6.1 behavior) — so make that
+    //    LOCAL git mutation VISIBLE, never silent: a created commit is local-only
+    //    and nothing is sent to Docmost.
+    await git.stageAll();
+    const committedWorkingTree = await git.commit("local: working-tree changes", {
+        authorName: LOCAL_AUTHOR_NAME,
+        authorEmail: LOCAL_AUTHOR_EMAIL,
+        trailers: [LOCAL_SOURCE_TRAILER],
+    });
+    if (committedWorkingTree) {
+        const sha = await git.revParse(DEFAULT_BRANCH);
+        log(`push: committed local working-tree changes on main` +
+            (sha ? ` as ${sha.slice(0, 8)}` : "") +
+            ` (local git only — nothing sent to Docmost).`);
+    }
+    else {
+        log("push: working tree clean (no local changes to push).");
+    }
+    // 4. Pick the diff BASE (SPEC §5/§6): `refs/docmost/last-pushed` if it resolves
+    //    (the marker of what `main` is already in Docmost), else fall back to the
+    //    `docmost` mirror branch (the mirror of what Docmost currently has) — which
+    //    is what exists before the first push ever advanced last-pushed.
+    let base;
+    const lastPushedSha = await git.readRef(LAST_PUSHED_REF);
+    if (lastPushedSha) {
+        base = { ref: LAST_PUSHED_REF, source: "last-pushed", sha: lastPushedSha };
+    }
+    else {
+        base = {
+            ref: DOCMOST_BRANCH,
+            source: "docmost",
+            sha: await git.revParse(DOCMOST_BRANCH),
+        };
+    }
+    const pushedCommit = await git.revParse(DEFAULT_BRANCH);
+    if (!pushedCommit) {
+        // `main` has no commit — `ensureRepo` always makes an initial one, so this is
+        // defensive. Nothing to diff.
+        log("push: `main` has no commit to push — nothing to do.");
+        return { mode: dryRun ? "dry-run" : "apply", base };
+    }
+    // 5. Diff the base against `main` and build the `metaAt` resolver (PURE planner
+    //    input). `current` reads the live working tree; `prev` reads the base ref's
+    //    pre-image via `git show <base>:<path>` (so a DELETE recovers its pageId).
+    const changes = await git.diffNameStatus(base.ref, DEFAULT_BRANCH);
+    // Synchronous resolver over PREFETCHED meta tables: `computePushActions` is
+    // PURE/sync, but the file/ref reads are async — so we prefetch every (path,
+    // side) the diff will ask for into a table first, then resolve from it.
+    const metaTable = new Map();
+    for (const change of changes) {
+        // `current`: A/M/R/C still have the file on `main`. `prev`: D needs the
+        // pre-image; R/C also benefit (old title). Prefetch both sides per path.
+        const currentPath = change.path;
+        const prevPath = change.oldPath ?? change.path;
+        if (!metaTable.has(`${currentPath}|current`)) {
+            metaTable.set(`${currentPath}|current`, await readMetaCurrent(deps, currentPath, settings.docmostSpaceId));
+        }
+        if (!metaTable.has(`${prevPath}|prev`)) {
+            metaTable.set(`${prevPath}|prev`, await readMetaPrev(deps, base.ref, prevPath, settings.docmostSpaceId));
+        }
+    }
+    const metaAt = (path, side) => metaTable.get(`${path}|${side}`) ?? null;
+    // The set of pageIds that STILL EXIST somewhere in the current `main` tree.
+    // Identity is the pageId, NOT the filename: a file vanishing from one path
+    // while the SAME pageId lives at another path is a MOVE (often a layout
+    // reshuffle of `_`-fallback names, whose two halves can even land in separate
+    // cycles), never a deletion. Built only when the diff contains deletes — the
+    // guard's whole job is to stop a phantom delete from trashing a live page.
+    let currentPageIds;
+    if (changes.some((c) => c.status === "D")) {
+        currentPageIds = new Set();
+        for (const relPath of await git.listTrackedFiles("*.md")) {
+            const pid = (await readMetaCurrent(deps, relPath, settings.docmostSpaceId))
+                ?.pageId;
+            if (pid)
+                currentPageIds.add(pid);
+        }
+    }
+    const actions = computePushActions({ changes, metaAt, currentPageIds });
+    const planned = {
+        creates: actions.creates.length,
+        updates: actions.updates.length,
+        deletes: actions.deletes.length,
+        renamesMoves: actions.renamesMoves.length,
+        skipped: actions.skipped.length,
+    };
+    // 6. DRY-RUN (default): log the full plan and RETURN — build NO client, make
+    //    ZERO Docmost calls, advance NO refs. This is the SAFE default.
+    logPlan(log, base, pushedCommit, actions, planned, dryRun);
+    if (dryRun) {
+        return { mode: "dry-run", base, pushedCommit, planned };
+    }
+    // 7. --apply: build the REAL client and execute. This is the ONLY write path.
+    const client = deps.makeClient(settings);
+    const applied = await applyPushActions({
+        client,
+        // Pass the WHOLE `git` object (it satisfies the applier's
+        // `Pick<VaultGit, ...>` deps surface). Passing bare method references
+        // (`git.updateRef`, …) would lose their `this` binding, so on a REAL
+        // `VaultGit` they would throw `this.runRaw is not a function`. Hand over
+        // the object so the methods keep their receiver — exactly as `pull.ts`
+        // does for `applyPullActions`.
+        git,
+        readFile: deps.readFile,
+        writeFile: deps.writeFile,
+        spaceId: settings.docmostSpaceId,
+    }, actions, pushedCommit);
+    // 7a. Persist freshly-assigned pageIds (creates) back into git. `applyPushActions`
+    //     rewrote those files on disk; commit them on `main` with the `local` trailer
+    //     so the new pageIds are recorded, then RE-advance `refs/docmost/last-pushed`
+    //     to the new commit so what Docmost mirrors and what last-pushed points at
+    //     stay in lock-step (the write-back commit is part of `main` now).
+    // Track a divergent-`docmost` mirror across BOTH ff sites (the applier's main
+    // push ff in 7b, and the write-back ff here). A divergent mirror is a §5
+    // invariant breach in EITHER branch and must escalate identically (exit 1).
+    let divergentDocmost = false;
+    if (applied.writtenBack.length > 0) {
+        await git.stageAll();
+        const recorded = await git.commit("local: record created pageIds", {
+            authorName: LOCAL_AUTHOR_NAME,
+            authorEmail: LOCAL_AUTHOR_EMAIL,
+            trailers: [LOCAL_SOURCE_TRAILER],
+        });
+        if (recorded) {
+            const newCommit = await git.revParse(DEFAULT_BRANCH);
+            // Only re-advance when the original push was CLEAN (last-pushed was already
+            // advanced by the applier); a partial push left the refs untouched and a
+            // re-run retries the whole batch, so we must not move them either.
+            if (newCommit && applied.lastPushedAdvanced) {
+                await git.updateRef(LAST_PUSHED_REF, newCommit);
+                const ff = await git.fastForwardBranch(DOCMOST_BRANCH, newCommit);
+                if (!ff.ok) {
+                    // SYMMETRIC with the main escalation (7b): a divergent mirror in the
+                    // write-back branch is the SAME §5 invariant breach and must escalate
+                    // (exit 1), not just log a soft warning.
+                    divergentDocmost = true;
+                    log(`push: WARNING — the 'docmost' mirror branch DIVERGED and was NOT ` +
+                        `fast-forwarded to the pageId write-back commit ` +
+                        `(${ff.reason ?? "not-fast-forward"}). The §5 invariant ('docmost' ` +
+                        `mirrors what Docmost contains) is broken: reconcile 'docmost' ` +
+                        `against the live Docmost tree before the next cycle.`);
+                }
+            }
+        }
+    }
+    // 7b. ESCALATE a divergent-`docmost` fast-forward refusal (SPEC §5 invariant
+    //     broken). The applier already refused to clobber a divergent mirror; make
+    //     it LOUD (not silent) so the operator notices, and fold it into the exit.
+    if (applied.docmostFastForward && !applied.docmostFastForward.ok) {
+        divergentDocmost = true;
+        log(`push: WARNING — the 'docmost' mirror branch DIVERGED and was NOT ` +
+            `fast-forwarded (${applied.docmostFastForward.reason ?? "not-fast-forward"}). ` +
+            `The §5 invariant ('docmost' mirrors what Docmost contains) is broken: ` +
+            `reconcile 'docmost' against the live Docmost tree before the next cycle.`);
+    }
+    // 7c. One-line summary (mirrors pull.ts's summary line).
+    log(`push complete: ${applied.created} created, ${applied.updated} updated, ` +
+        `${applied.deleted} deleted, ${applied.moved} moved, ${applied.renamed} ` +
+        `renamed, ${applied.noops.length} no-op(s), ${applied.skipped.length} ` +
+        `skipped, ${applied.failures.length} failure(s)` +
+        (divergentDocmost ? " [DIVERGENT docmost mirror]" : ""));
+    return {
+        mode: "apply",
+        base,
+        pushedCommit,
+        planned,
+        applied,
+        divergentDocmost,
+        failures: applied.failures,
+    };
+}
+/** Synthetic native meta from the live working tree (`current` side). */
+async function readMetaCurrent(deps, path, spaceId) {
+    let text;
+    try {
+        text = await deps.readFile(path);
+    }
+    catch {
+        return null; // absent on disk (e.g. a D row's path) -> no current meta.
+    }
+    return nativeMeta(text, path, spaceId);
+}
+/** Synthetic native meta from the base ref's pre-image (`prev` side). */
+async function readMetaPrev(deps, baseRef, path, spaceId) {
+    let text;
+    try {
+        text = await deps.git.showFileAtRef(baseRef, path);
+    }
+    catch {
+        return null;
+    }
+    if (text === null)
+        return null; // path absent at the base ref.
+    return nativeMeta(text, path, spaceId);
+}
+/** Emit the full plan (counts + per-item) to the injected logger. */
+function logPlan(log, base, pushedCommit, actions, planned, dryRun) {
+    log(`push plan (${dryRun ? "DRY-RUN — no Docmost writes" : "APPLY"}): base=` +
+        `${base.ref} (${base.source}${base.sha ? ` ${base.sha.slice(0, 8)}` : ""}) ` +
+        `-> main ${pushedCommit.slice(0, 8)}`);
+    log(`push plan counts: ${planned.creates} create, ${planned.updates} update, ` +
+        `${planned.deletes} delete, ${planned.renamesMoves} rename/move, ` +
+        `${planned.skipped} skipped`);
+    for (const c of actions.creates)
+        log(`  create: ${c.path}`);
+    for (const u of actions.updates)
+        log(`  update: ${u.pageId} (${u.path})`);
+    for (const d of actions.deletes)
+        log(`  delete: ${d.pageId}`);
+    for (const rm of actions.renamesMoves)
+        log(`  rename/move: ${rm.oldPath} -> ${rm.newPath} (${rm.pageId})`);
+    for (const s of actions.skipped)
+        log(`  skipped [${s.status}] ${s.path}: ${s.reason}`);
+}
+/**
+ * Parse the `push` CLI flags. SAFE BY DEFAULT: without `--apply` the run is a
+ * DRY-RUN (plan only). Exported so the flag handling is unit-testable.
+ */
+export function parseArgs(argv) {
+    return { apply: argv.includes("--apply") };
+}

packages/git-sync/build/engine/reconcile.d.ts

@@ -0,0 +1,126 @@
+/**
+ * Pure reconciliation planner (SPEC §5/§6/§8).
+ *
+ * Given the desired live set of files (computed from the current Docmost tree)
+ * and the set of files currently tracked in the vault, compute what to write,
+ * what to move (old path to remove), and what to delete. Identity is `pageId`
+ * (the stable file<->page anchor, SPEC §4): a page that keeps its pageId but
+ * changes relPath is a MOVE, not delete+add; a tracked pageId that is gone from
+ * the live tree is a DELETE.
+ *
+ * This module is intentionally PURE (no IO, no git) so the whole plan is
+ * unit-testable. The actual file writing / git operations happen in pull.ts.
+ */
+/** A page that SHOULD exist in the vault at a given path. */
+export interface LiveEntry {
+    pageId: string;
+    /** Vault-relative path (forward-slash), e.g. `Space/Parent/Child.md`. */
+    relPath: string;
+}
+/** A page currently tracked in the vault (pageId parsed from its meta). */
+export interface ExistingEntry {
+    pageId: string;
+    /** Vault-relative path (forward-slash) of the tracked file. */
+    relPath: string;
+}
+/** A page to (re)write at its destination path. */
+export interface WriteEntry {
+    pageId: string;
+    relPath: string;
+}
+/** A page that moved: written at its NEW relPath, with the OLD path removed. */
+export interface MovedEntry {
+    pageId: string;
+    fromRelPath: string;
+    toRelPath: string;
+    /**
+     * Whether the old path (`fromRelPath`) is SAFE to remove. False when another
+     * live page will (re)write that exact path (path reuse): removing it would
+     * destroy real data, so the caller must skip the removal. The move itself is
+     * still recorded (the new path is written regardless).
+     */
+    removeOldPath: boolean;
+}
+/** The full reconciliation plan. */
+export interface ReconciliationPlan {
+    /**
+     * Pages present in `live` -> (re)write at their relPath. This naturally
+     * covers add, content-update (same path) AND move (same pageId, new path),
+     * since every live page is (re)written regardless of whether it existed.
+     */
+    toWrite: WriteEntry[];
+    /**
+     * Vault-relative paths to delete because their tracked pageId is ABSENT from
+     * `live` (page removed/trashed). This set is ONLY absence-based deletions —
+     * the OLD paths of moved pages are NOT here (they live in `moved` and are
+     * applied separately by the caller). Keeping the two apart lets pull.ts gate
+     * absence deletions behind the incomplete-fetch suppression + mass-delete
+     * guard (SPEC §8) while still applying real moves.
+     */
+    toDelete: string[];
+    /**
+     * Tracked pages whose relPath changed. The caller writes the page at
+     * `toRelPath`, then removes `fromRelPath` — but ONLY after the new-path write
+     * succeeded. The old path is NOT in `toDelete`.
+     */
+    moved: MovedEntry[];
+}
+/**
+ * Compute the reconciliation plan.
+ *
+ * Rules:
+ *   - Every `live` page is written at its relPath (covers add + update + move).
+ *   - A tracked pageId present in `live` whose relPath changed is `moved`; its
+ *     OLD relPath goes into `moved` ONLY (the caller removes it after the new
+ *     path is written) and is NEVER added to `toDelete`.
+ *   - A tracked pageId NOT present in `live` is an ABSENCE delete; its relPath
+ *     is added to `toDelete`.
+ *
+ * Notes:
+ *   - Safety filter (no data loss): no path that is a live TARGET path of any
+ *     page is ever deleted/removed (a write owns it). This applies to BOTH the
+ *     absence `toDelete` set AND a moved page's old-path removal — if a moved
+ *     page's OLD path is reused by ANOTHER live page, the move records no old
+ *     path to remove, because that path will be (re)written.
+ *   - `existing` may legitimately contain duplicate pageIds (two stray files
+ *     carrying the same meta pageId); each such file that is not the live target
+ *     path is removed (as an absence/move) so the vault converges to exactly the
+ *     live set.
+ */
+export declare function planReconciliation(live: LiveEntry[], existing: ExistingEntry[]): ReconciliationPlan;
+/**
+ * Below this many tracked files the mass-delete fraction guard is not applied
+ * (a tiny vault where deleting "most" files is normal, e.g. 1-of-2).
+ */
+export declare const MASS_DELETE_MIN_EXISTING = 4;
+/** Fraction of tracked files above which a delete plan is a suspected wipe. */
+export declare const MASS_DELETE_FRACTION = 0.5;
+/** Why absence-based deletions were (or were not) applied this cycle. */
+export type DeletionDecision = {
+    apply: true;
+} | {
+    apply: false;
+    reason: "incomplete-fetch" | "empty-live" | "mass-delete";
+};
+/**
+ * Pure decision: should the ABSENCE-based deletions (`plan.toDelete`) be applied
+ * this cycle? Encapsulates the SPEC §8 safety invariants so they are unit-
+ * testable without live creds or git:
+ *
+ *   - `treeComplete === false` (a partial Docmost tree fetch) -> SUPPRESS. A page
+ *     missing from a partial tree is NOT proof of deletion (SPEC §8); we must not
+ *     delete merely-absent files this cycle. (Writes/updates/moves still happen.)
+ *   - The live fetch returned 0 pages while files are tracked -> SUPPRESS
+ *     (almost always a failed fetch, never a real "delete everything").
+ *   - The plan would delete more than `MASS_DELETE_FRACTION` of a non-trivial
+ *     vault -> SUPPRESS as a mass-deletion guard (defense in depth).
+ *
+ * Moves are NOT governed by this decision: a moved page IS present in `live`, so
+ * its old-path removal is real (handled by the caller separately).
+ */
+export declare function decideAbsenceDeletions(args: {
+    treeComplete: boolean;
+    liveCount: number;
+    existingCount: number;
+    deleteCount: number;
+}): DeletionDecision;

packages/git-sync/build/engine/reconcile.js

@@ -0,0 +1,117 @@
+/**
+ * Pure reconciliation planner (SPEC §5/§6/§8).
+ *
+ * Given the desired live set of files (computed from the current Docmost tree)
+ * and the set of files currently tracked in the vault, compute what to write,
+ * what to move (old path to remove), and what to delete. Identity is `pageId`
+ * (the stable file<->page anchor, SPEC §4): a page that keeps its pageId but
+ * changes relPath is a MOVE, not delete+add; a tracked pageId that is gone from
+ * the live tree is a DELETE.
+ *
+ * This module is intentionally PURE (no IO, no git) so the whole plan is
+ * unit-testable. The actual file writing / git operations happen in pull.ts.
+ */
+/**
+ * Compute the reconciliation plan.
+ *
+ * Rules:
+ *   - Every `live` page is written at its relPath (covers add + update + move).
+ *   - A tracked pageId present in `live` whose relPath changed is `moved`; its
+ *     OLD relPath goes into `moved` ONLY (the caller removes it after the new
+ *     path is written) and is NEVER added to `toDelete`.
+ *   - A tracked pageId NOT present in `live` is an ABSENCE delete; its relPath
+ *     is added to `toDelete`.
+ *
+ * Notes:
+ *   - Safety filter (no data loss): no path that is a live TARGET path of any
+ *     page is ever deleted/removed (a write owns it). This applies to BOTH the
+ *     absence `toDelete` set AND a moved page's old-path removal — if a moved
+ *     page's OLD path is reused by ANOTHER live page, the move records no old
+ *     path to remove, because that path will be (re)written.
+ *   - `existing` may legitimately contain duplicate pageIds (two stray files
+ *     carrying the same meta pageId); each such file that is not the live target
+ *     path is removed (as an absence/move) so the vault converges to exactly the
+ *     live set.
+ */
+export function planReconciliation(live, existing) {
+    // Desired path for each live pageId.
+    const liveByPageId = new Map();
+    // Set of all paths that WILL be written (never delete/remove one of these).
+    const liveTargetPaths = new Set();
+    for (const e of live) {
+        liveByPageId.set(e.pageId, e.relPath);
+        liveTargetPaths.add(e.relPath);
+    }
+    const toWrite = live.map((e) => ({
+        pageId: e.pageId,
+        relPath: e.relPath,
+    }));
+    const moved = [];
+    // Absence-based deletions ONLY (tracked pageId absent from `live`). Use a Set
+    // so the same path coming from multiple existing rows is queued only once.
+    const toDeleteSet = new Set();
+    for (const ex of existing) {
+        const liveRel = liveByPageId.get(ex.pageId);
+        if (liveRel === undefined) {
+            // Tracked page is gone from the live tree -> absence delete.
+            // Never queue a path a live page will (re)write (path reuse -> no loss).
+            if (!liveTargetPaths.has(ex.relPath))
+                toDeleteSet.add(ex.relPath);
+            continue;
+        }
+        if (liveRel !== ex.relPath) {
+            // Same pageId, different path -> a MOVE. Record it so the caller can write
+            // the new path first, then remove the old one. If the old path is itself a
+            // live target (reused by another page), it must NOT be removed — the write
+            // owns it — so flag `removeOldPath: false` (move still recorded).
+            moved.push({
+                pageId: ex.pageId,
+                fromRelPath: ex.relPath,
+                toRelPath: liveRel,
+                removeOldPath: !liveTargetPaths.has(ex.relPath),
+            });
+        }
+        // liveRel === ex.relPath -> content-update in place; nothing extra to do
+        // (the write above re-emits the file; identical bytes => git no-op).
+    }
+    const toDelete = [...toDeleteSet];
+    return { toWrite, toDelete, moved };
+}
+/**
+ * Below this many tracked files the mass-delete fraction guard is not applied
+ * (a tiny vault where deleting "most" files is normal, e.g. 1-of-2).
+ */
+export const MASS_DELETE_MIN_EXISTING = 4;
+/** Fraction of tracked files above which a delete plan is a suspected wipe. */
+export const MASS_DELETE_FRACTION = 0.5;
+/**
+ * Pure decision: should the ABSENCE-based deletions (`plan.toDelete`) be applied
+ * this cycle? Encapsulates the SPEC §8 safety invariants so they are unit-
+ * testable without live creds or git:
+ *
+ *   - `treeComplete === false` (a partial Docmost tree fetch) -> SUPPRESS. A page
+ *     missing from a partial tree is NOT proof of deletion (SPEC §8); we must not
+ *     delete merely-absent files this cycle. (Writes/updates/moves still happen.)
+ *   - The live fetch returned 0 pages while files are tracked -> SUPPRESS
+ *     (almost always a failed fetch, never a real "delete everything").
+ *   - The plan would delete more than `MASS_DELETE_FRACTION` of a non-trivial
+ *     vault -> SUPPRESS as a mass-deletion guard (defense in depth).
+ *
+ * Moves are NOT governed by this decision: a moved page IS present in `live`, so
+ * its old-path removal is real (handled by the caller separately).
+ */
+export function decideAbsenceDeletions(args) {
+    const { treeComplete, liveCount, existingCount, deleteCount } = args;
+    // No tracked files, or nothing to delete -> trivially fine to "apply".
+    if (existingCount === 0 || deleteCount === 0)
+        return { apply: true };
+    if (!treeComplete)
+        return { apply: false, reason: "incomplete-fetch" };
+    if (liveCount === 0)
+        return { apply: false, reason: "empty-live" };
+    if (existingCount >= MASS_DELETE_MIN_EXISTING &&
+        deleteCount > existingCount * MASS_DELETE_FRACTION) {
+        return { apply: false, reason: "mass-delete" };
+    }
+    return { apply: true };
+}

packages/git-sync/build/engine/roundtrip-helpers.d.ts

@@ -0,0 +1,21 @@
+/**
+ * Pure, IO-free comparison helpers for the idempotency round-trip checks. The
+ * round-trip harness that drives these lives in the package's tests, not in the
+ * engine.
+ */
+/**
+ * Recursively strip every `attrs.id` from a ProseMirror node tree. Block ids
+ * are regenerated by `markdownToProseMirror` (SPEC §11), so they must be
+ * ignored when comparing the semantic shape of two documents. Returns a NEW
+ * tree; the input is not mutated.
+ */
+export declare function stripBlockIds(node: any): any;
+/**
+ * Find the first divergence between two values via a recursive deep compare.
+ * Returns a short path + the two differing values, or null if they are equal.
+ */
+export declare function firstDivergence(a: any, b: any, path?: string): {
+    path: string;
+    a: any;
+    b: any;
+} | null;

packages/git-sync/build/engine/roundtrip-helpers.js

@@ -0,0 +1,70 @@
+/**
+ * Pure, IO-free comparison helpers for the idempotency round-trip checks. The
+ * round-trip harness that drives these lives in the package's tests, not in the
+ * engine.
+ */
+/**
+ * Recursively strip every `attrs.id` from a ProseMirror node tree. Block ids
+ * are regenerated by `markdownToProseMirror` (SPEC §11), so they must be
+ * ignored when comparing the semantic shape of two documents. Returns a NEW
+ * tree; the input is not mutated.
+ */
+export function stripBlockIds(node) {
+    if (Array.isArray(node)) {
+        return node.map(stripBlockIds);
+    }
+    if (node && typeof node === "object") {
+        const out = {};
+        for (const key of Object.keys(node)) {
+            if (key === "attrs" && node.attrs && typeof node.attrs === "object") {
+                // Drop the `id` attr; keep every other attribute.
+                const { id, ...rest } = node.attrs;
+                void id;
+                out.attrs = stripBlockIds(rest);
+            }
+            else {
+                out[key] = stripBlockIds(node[key]);
+            }
+        }
+        return out;
+    }
+    return node;
+}
+/**
+ * Find the first divergence between two values via a recursive deep compare.
+ * Returns a short path + the two differing values, or null if they are equal.
+ */
+export function firstDivergence(a, b, path = "$") {
+    if (a === b)
+        return null;
+    const ta = typeof a;
+    const tb = typeof b;
+    if (ta !== tb || a === null || b === null) {
+        return { path, a, b };
+    }
+    if (ta !== "object") {
+        return { path, a, b };
+    }
+    const aIsArr = Array.isArray(a);
+    const bIsArr = Array.isArray(b);
+    if (aIsArr !== bIsArr)
+        return { path, a, b };
+    if (aIsArr) {
+        if (a.length !== b.length) {
+            return { path: `${path}.length`, a: a.length, b: b.length };
+        }
+        for (let i = 0; i < a.length; i++) {
+            const d = firstDivergence(a[i], b[i], `${path}[${i}]`);
+            if (d)
+                return d;
+        }
+        return null;
+    }
+    const keys = new Set([...Object.keys(a), ...Object.keys(b)]);
+    for (const k of keys) {
+        const d = firstDivergence(a[k], b[k], `${path}.${k}`);
+        if (d)
+            return d;
+    }
+    return null;
+}

packages/git-sync/build/engine/sanitize.d.ts

@@ -0,0 +1,23 @@
+/**
+ * Deterministic filename strategy (SPEC §12).
+ *
+ * The file name is COSMETIC — the source of truth for the file<->page link is
+ * `pageId` / `slugId` inside the meta block, so renaming a file is safe. These
+ * functions are intentionally dependency-free and pure, so they are trivially
+ * unit-testable.
+ */
+/**
+ * Sanitize a page title into a safe file-name component (WITHOUT extension).
+ *
+ * Steps: replace forbidden / control characters with "-", collapse whitespace
+ * runs to a single space, trim, cap the length, then guard against an empty
+ * result, an all-dots result, or a reserved Windows device name by prefixing
+ * with "_".
+ */
+export declare function sanitizeTitle(title: string): string;
+/**
+ * Disambiguate a sanitized name when two siblings in the same folder collapse
+ * to the same name. Appends a stable suffix built from the page's `slugId`, so
+ * the result stays deterministic across runs (SPEC §12: `Title ~slugId`).
+ */
+export declare function disambiguate(name: string, slugId: string): string;

packages/git-sync/build/engine/sanitize.js

@@ -0,0 +1,97 @@
+/**
+ * Deterministic filename strategy (SPEC §12).
+ *
+ * The file name is COSMETIC — the source of truth for the file<->page link is
+ * `pageId` / `slugId` inside the meta block, so renaming a file is safe. These
+ * functions are intentionally dependency-free and pure, so they are trivially
+ * unit-testable.
+ */
+// Printable characters forbidden in file names on common filesystems (mainly
+// Windows): / \ < > : " | ? *. Each match is replaced with a single "-".
+// Spaces are NOT in this set; whitespace is normalized separately below.
+// ASCII control characters (code points 0..31) are stripped in a separate pass
+// (see stripControlChars) to keep this literal free of embedded control bytes.
+const FORBIDDEN_PRINTABLE_RE = /[/\\<>:"|?*]/g;
+// Runs of whitespace (including tabs/newlines) collapse to a single space.
+const WHITESPACE_RUN_RE = /\s+/g;
+// Reserved Windows device names (case-insensitive). A bare match (with or
+// without an extension) is unusable as a file name, so it is prefixed with "_".
+const RESERVED_WINDOWS_NAMES = new Set([
+    "con",
+    "prn",
+    "aux",
+    "nul",
+    "com1",
+    "com2",
+    "com3",
+    "com4",
+    "com5",
+    "com6",
+    "com7",
+    "com8",
+    "com9",
+    "lpt1",
+    "lpt2",
+    "lpt3",
+    "lpt4",
+    "lpt5",
+    "lpt6",
+    "lpt7",
+    "lpt8",
+    "lpt9",
+]);
+// Cap on the sanitized length to stay well within filesystem path-component
+// limits (255 bytes on most FSes) while leaving room for an extension and a
+// disambiguation suffix.
+const MAX_LENGTH = 120;
+/**
+ * Replace every ASCII control character (code points 0..31) with "-". Done by
+ * scanning code points rather than a control-range regex literal, so the source
+ * file carries no embedded control bytes.
+ */
+function stripControlChars(input) {
+    let out = "";
+    for (let i = 0; i < input.length; i++) {
+        out += input.charCodeAt(i) < 32 ? "-" : input[i];
+    }
+    return out;
+}
+/**
+ * Sanitize a page title into a safe file-name component (WITHOUT extension).
+ *
+ * Steps: replace forbidden / control characters with "-", collapse whitespace
+ * runs to a single space, trim, cap the length, then guard against an empty
+ * result, an all-dots result, or a reserved Windows device name by prefixing
+ * with "_".
+ */
+export function sanitizeTitle(title) {
+    let name = stripControlChars(title ?? "")
+        .replace(FORBIDDEN_PRINTABLE_RE, "-")
+        .replace(WHITESPACE_RUN_RE, " ")
+        .trim();
+    if (name.length > MAX_LENGTH) {
+        name = name.slice(0, MAX_LENGTH).trim();
+    }
+    // Compare the base name (before the first dot) against reserved names, so
+    // both "CON" and "con.md" are caught.
+    const base = name.split(".")[0]?.toLowerCase() ?? "";
+    // A name that is empty, consists only of dots ("." / ".." / "..."), or is a
+    // reserved Windows device name is unusable as a path component. The all-dots
+    // case is a path-traversal hazard in particular: an unprefixed ".." would
+    // become a parent-directory segment and let a page escape the vault, so it
+    // MUST be neutralized here (becomes "_..", which is a literal file name).
+    if (name.length === 0 ||
+        /^\.+$/.test(name) ||
+        RESERVED_WINDOWS_NAMES.has(base)) {
+        name = "_" + name;
+    }
+    return name;
+}
+/**
+ * Disambiguate a sanitized name when two siblings in the same folder collapse
+ * to the same name. Appends a stable suffix built from the page's `slugId`, so
+ * the result stays deterministic across runs (SPEC §12: `Title ~slugId`).
+ */
+export function disambiguate(name, slugId) {
+    return `${name} ~${slugId}`;
+}

packages/git-sync/build/engine/settings.d.ts

@@ -0,0 +1,41 @@
+/**
+ * Engine settings.
+ *
+ * The engine is driven IN-PROCESS by the NestJS server, which builds the
+ * `Settings` object from `EnvironmentService` — so this module must NOT reach
+ * into `process.env`. It exposes only:
+ *   - the `Settings` type the engine consumes, and
+ *   - `parseSettings(env)` as a PURE function (validate a raw env object -> typed
+ *     `Settings`), kept for unit tests and for the server to reuse if it wants
+ *     to validate an env-shaped object.
+ * There is no `.env`-loading side-effecting entry point.
+ */
+import { z } from 'zod';
+export declare const envSchema: z.ZodObject<{
+    DOCMOST_API_URL: z.ZodString;
+    DOCMOST_EMAIL: z.ZodString;
+    DOCMOST_PASSWORD: z.ZodString;
+    DOCMOST_SPACE_ID: z.ZodString;
+    VAULT_PATH: z.ZodDefault<z.ZodString>;
+    GIT_REMOTE: z.ZodPipe<z.ZodTransform<unknown, unknown>, z.ZodOptional<z.ZodString>>;
+    POLL_INTERVAL_MS: z.ZodDefault<z.ZodCoercedNumber<unknown>>;
+    DEBOUNCE_MS: z.ZodDefault<z.ZodCoercedNumber<unknown>>;
+    LOG_LEVEL: z.ZodDefault<z.ZodEnum<{
+        info: "info";
+        error: "error";
+        debug: "debug";
+        warn: "warn";
+    }>>;
+}, z.core.$strip>;
+export type Settings = {
+    docmostApiUrl: string;
+    docmostEmail: string;
+    docmostPassword: string;
+    docmostSpaceId: string;
+    vaultPath: string;
+    gitRemote?: string;
+    pollIntervalMs: number;
+    debounceMs: number;
+    logLevel: 'debug' | 'info' | 'warn' | 'error';
+};
+export declare function parseSettings(env: NodeJS.ProcessEnv): Settings;

packages/git-sync/build/engine/settings.js

@@ -0,0 +1,49 @@
+/**
+ * Engine settings.
+ *
+ * The engine is driven IN-PROCESS by the NestJS server, which builds the
+ * `Settings` object from `EnvironmentService` — so this module must NOT reach
+ * into `process.env`. It exposes only:
+ *   - the `Settings` type the engine consumes, and
+ *   - `parseSettings(env)` as a PURE function (validate a raw env object -> typed
+ *     `Settings`), kept for unit tests and for the server to reuse if it wants
+ *     to validate an env-shaped object.
+ * There is no `.env`-loading side-effecting entry point.
+ */
+import { z } from 'zod';
+// Schema keyed by the real ENV variable names so validation errors name the
+// exact variable. Credentials and the address of our OWN Docmost instance have
+// NO default — a missing value must fail at startup, never silently fall back.
+export const envSchema = z.object({
+    // Docmost connection — address of our own instance, no default.
+    DOCMOST_API_URL: z.string().url(),
+    // Credentials for /auth/login — no default, never hardcoded.
+    DOCMOST_EMAIL: z.string().min(1),
+    DOCMOST_PASSWORD: z.string().min(1),
+    // Which Docmost space to mirror.
+    DOCMOST_SPACE_ID: z.string().min(1),
+    // Local git vault (state store) — kept under data/ so the volume persists it.
+    VAULT_PATH: z.string().min(1).default('data/vault'),
+    // Optional git remote the vault pushes to. Empty string is treated as unset.
+    GIT_REMOTE: z.preprocess((v) => (v === '' ? undefined : v), z.string().min(1).optional()),
+    // Non-secret tunables — sensible defaults are fine.
+    POLL_INTERVAL_MS: z.coerce.number().int().positive().default(15000),
+    DEBOUNCE_MS: z.coerce.number().int().positive().default(2000),
+    LOG_LEVEL: z.enum(['debug', 'info', 'warn', 'error']).default('info'),
+});
+// Pure: validate a raw environment object and map it to a typed Settings.
+// Throws ZodError on bad config. No side effects — safe to import in tests.
+export function parseSettings(env) {
+    const e = envSchema.parse(env);
+    return {
+        docmostApiUrl: e.DOCMOST_API_URL,
+        docmostEmail: e.DOCMOST_EMAIL,
+        docmostPassword: e.DOCMOST_PASSWORD,
+        docmostSpaceId: e.DOCMOST_SPACE_ID,
+        vaultPath: e.VAULT_PATH,
+        gitRemote: e.GIT_REMOTE,
+        pollIntervalMs: e.POLL_INTERVAL_MS,
+        debounceMs: e.DEBOUNCE_MS,
+        logLevel: e.LOG_LEVEL,
+    };
+}

packages/git-sync/build/engine/stabilize.d.ts

@@ -0,0 +1,41 @@
+/**
+ * Meta object as `exportPageBody` builds it (SPEC §4). Kept byte-for-byte
+ * compatible so files produced here match `exportPageBody`'s output exactly.
+ */
+export interface PageMeta {
+    version: 1;
+    pageId: string;
+    slugId: string;
+    title: string;
+    spaceId: string;
+    parentPageId: string | null;
+}
+/**
+ * Produce the self-contained `.md` file text for a page from its raw
+ * ProseMirror `content` + identity meta, in the verified fixpoint form.
+ *
+ *   md1        = convertProseMirrorToMarkdown(content)
+ *   doc2       = markdownToProseMirror(md1)            // one import...
+ *   stableBody = convertProseMirrorToMarkdown(doc2)    // ...and re-export
+ *   file       = serializeDocmostMarkdownBody(meta, stableBody)
+ *
+ * The single export->import->export pass is the verified fixpoint (SPEC §11):
+ * idempotent for already-stable content, and the convergence point for the
+ * known converter asymmetries.
+ */
+export declare function stabilizePageFile(content: unknown, meta: PageMeta): Promise<string>;
+/**
+ * The fixpoint markdown BODY for a page's ProseMirror `content`, WITHOUT any meta
+ * envelope:
+ *
+ *   md1        = convertProseMirrorToMarkdown(content)   // export...
+ *   doc2       = markdownToProseMirror(md1)              // ...import...
+ *   stableBody = convertProseMirrorToMarkdown(doc2)      // ...re-export
+ *
+ * The single export->import->export pass is the verified fixpoint (SPEC §11):
+ * idempotent for already-stable content, and the convergence point for the known
+ * converter asymmetries. The native-Obsidian writer (`serializePageFile`) wraps
+ * this body with a minimal `gitmost_id` frontmatter; determinism here is what
+ * keeps re-pulls of an unchanged page byte-identical (no churn, loop-guard).
+ */
+export declare function stabilizePageBody(content: unknown): Promise<string>;

packages/git-sync/build/engine/stabilize.js

@@ -0,0 +1,52 @@
+/**
+ * Normalize-on-write helper (SPEC §11 "Резолюция").
+ *
+ * git diffs byte-for-byte, so writing a page in a NON-fixpoint markdown form
+ * would make the next pull re-export it to a slightly different (but stable)
+ * form and produce a phantom diff -> churny commits. The converter has a couple
+ * of known one-pass asymmetries (a block image after a paragraph adds an empty
+ * paragraph; a diagram materializes `data-align`), all of which converge to a
+ * fixpoint after ONE `export -> import -> export` round-trip.
+ *
+ * So at write time we run exactly that one pass and persist the fixpoint form.
+ * Already-stable content is unaffected (the pass is idempotent), so re-pulls of
+ * unchanged pages produce identical bytes and git sees no diff.
+ */
+import { convertProseMirrorToMarkdown, markdownToProseMirror, serializeDocmostMarkdownBody, } from "../lib/index.js";
+/**
+ * Produce the self-contained `.md` file text for a page from its raw
+ * ProseMirror `content` + identity meta, in the verified fixpoint form.
+ *
+ *   md1        = convertProseMirrorToMarkdown(content)
+ *   doc2       = markdownToProseMirror(md1)            // one import...
+ *   stableBody = convertProseMirrorToMarkdown(doc2)    // ...and re-export
+ *   file       = serializeDocmostMarkdownBody(meta, stableBody)
+ *
+ * The single export->import->export pass is the verified fixpoint (SPEC §11):
+ * idempotent for already-stable content, and the convergence point for the
+ * known converter asymmetries.
+ */
+export async function stabilizePageFile(content, meta) {
+    // The meta shape is exactly what `exportPageBody` writes; cast to the lib's
+    // DocmostMdMeta (a superset with optional fields) for the serializer.
+    return serializeDocmostMarkdownBody(meta, await stabilizePageBody(content));
+}
+/**
+ * The fixpoint markdown BODY for a page's ProseMirror `content`, WITHOUT any meta
+ * envelope:
+ *
+ *   md1        = convertProseMirrorToMarkdown(content)   // export...
+ *   doc2       = markdownToProseMirror(md1)              // ...import...
+ *   stableBody = convertProseMirrorToMarkdown(doc2)      // ...re-export
+ *
+ * The single export->import->export pass is the verified fixpoint (SPEC §11):
+ * idempotent for already-stable content, and the convergence point for the known
+ * converter asymmetries. The native-Obsidian writer (`serializePageFile`) wraps
+ * this body with a minimal `gitmost_id` frontmatter; determinism here is what
+ * keeps re-pulls of an unchanged page byte-identical (no churn, loop-guard).
+ */
+export async function stabilizePageBody(content) {
+    const md1 = convertProseMirrorToMarkdown(content);
+    const doc2 = await markdownToProseMirror(md1);
+    return convertProseMirrorToMarkdown(doc2);
+}