fix(page,ai-chat): address PR #200 review — canonical lock UUIDs, changelog, tests

- page.service: lock concurrent re-parents by canonical row UUIDs
  (`movedPage.id`, not the raw client `dto.pageId` which may be a slugId) so
  two opposing moves passing slugIds can't sort into different FOR UPDATE
  orders and deadlock (#159).
- CHANGELOG: add [Unreleased] entries — Fixed #159 (serialized concurrent
  moves + in-tx cycle re-check), Added #190 (model-friendly tool-input errors).
- page.service.spec: hoist the duplicated `makeChain` trx-stub Proxy into one
  module-level helper (was 3 copies); add a move-to-root test covering the
  unlocked else-branch (no transaction opened, updatePage called without a trx).
- model-friendly-input.spec: cover the duplicate-path dedup branch in
  formatIssues — a single param with two zod issues is named only once.

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

CHANGELOG.md

@@ -43,13 +43,6 @@ 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)
-- **AI chat "Context window (tokens)" setting (`chatContextWindow`).** A new
-  admin field in AI settings that records the chat model's context-window size.
-  When set (> 0) it becomes the denominator of the header context-badge, which
-  now reads "used / max"; `0`/empty clears the limit and the badge shows only
-  the current context as before. There is no provider-independent way to read a
-  model's window automatically, so it is an explicit workspace-level value.
-  (#189)
 - **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
@@ -59,6 +52,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **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)
+- **Model-friendly AI-chat tool-input errors.** When the model calls an in-app
+  AI tool with bad arguments, the validation failure is now a concise,
+  human-readable message that NAMES each offending parameter (by its dotted
+  path) and appends a fixed retry hint ("include every REQUIRED parameter…, do
+  not drop ids like `pageId`"), instead of the raw zod text. This nudges the
+  model to re-issue the call correctly — particularly in parallel tool-call
+  batches where it tends to drop a repeated id. The required/optional contract
+  and unknown-key stripping are unchanged. (#190)
 
 ### Changed
 
@@ -68,12 +69,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   model's reasoning out of the box. An endpoint that is real OpenAI behind a
   custom base URL should set the new `chatApiStyle` "Protocol" to `openai`. (#177)
 
-- **AI chat header context-badge now shows "used / max".** When an admin sets
-  the new `chatContextWindow`, the badge displays the current context size over
-  the configured window (e.g. `120k / 200k`) instead of switching to a live
-  per-turn token counter during streaming. With no window configured the badge
-  keeps showing just the current context. (#189)
-
 - **Footnotes now reuse (Pandoc semantics).** Multiple `[^a]` references to the
   same id are ONE footnote — one number, one definition, several back-references
   — instead of being renamed to `a__2`, `a__3`. Duplicate `[^a]:` definitions are
@@ -105,6 +100,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   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)
+- **Concurrent page moves can no longer lose a subtree to a cycle.** Two
+  opposing re-parents racing each other (A: X under Y, B: Y under X) could each
+  pass a cycle check built from a stale snapshot and commit a cycle, orphaning a
+  subtree. A genuine re-parent under a concrete parent now serializes: it locks
+  the moved page and the destination parent `FOR UPDATE` in a canonical
+  (UUID-sorted) order — so opposing moves can't deadlock — and re-runs the cycle
+  check INSIDE the transaction against the now-committed state. Same-parent
+  reorders and moves to root keep the lock-free path. (#159)
 
 ## [0.93.0] - 2026-06-21
 

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

@@ -1168,10 +1168,7 @@
   "Built-in assistant persona": "Built-in assistant persona",
   "Minimize": "Minimize",
   "Current context size": "Current context size",
-  "Context size / model limit": "Context size / model limit",
-  "Context window (tokens)": "Context window (tokens)",
-  "Shows used / total in the chat header badge; empty hides the total.": "Shows used / total in the chat header badge; empty hides the total.",
-  "e.g. 200000": "e.g. 200000",
+  "Tokens generated this turn": "Tokens generated this turn",
   "AI agent": "AI agent",
   "Take a look at the current document": "Take a look at the current document",
   "AI agent is typing…": "AI agent is typing…",

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

@@ -705,10 +705,7 @@
   "Copy chat": "Копировать чат",
   "Created successfully": "Успешно создано",
   "Current context size": "Текущий размер контекста",
-  "Context size / model limit": "Размер контекста / лимит модели",
-  "Context window (tokens)": "Размер окна контекста (токены)",
-  "Shows used / total in the chat header badge; empty hides the total.": "Показывает использовано/всего в шапке чата; пусто — скрыть лимит.",
-  "e.g. 200000": "напр. 200000",
+  "Tokens generated this turn": "Токенов сгенерировано за ход",
   "Delete this chat?": "Удалить этот чат?",
   "Deleted successfully": "Успешно удалено",
   "Edited by AI agent on behalf of {{name}}": "Отредактировано AI-агентом от имени {{name}}",

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

@@ -6,7 +6,7 @@ import {
   useRef,
   useState,
 } from "react";
-import { Group, Loader } from "@mantine/core";
+import { Group, Loader, Tooltip } from "@mantine/core";
 import {
   IconArrowsDiagonal,
   IconCheck,
@@ -39,7 +39,6 @@ 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 { ContextBadge } from "@/features/ai-chat/components/context-badge.tsx";
 import { exportAiChat } from "@/features/ai-chat/services/ai-chat-service.ts";
 import { useChatSession } from "@/features/ai-chat/hooks/use-chat-session.ts";
 import {
@@ -61,6 +60,13 @@ const MIN_HEIGHT = 400;
 // Margin kept between the window and the viewport edges while dragging.
 const EDGE_MARGIN = 8;
 
+/** Compact token formatter: 1.2M / 3.4k / 950. */
+function formatTokens(n: number): string {
+  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1)}M`;
+  if (n >= 1_000) return `${(n / 1_000).toFixed(1)}k`;
+  return String(n);
+}
+
 // Compute the initial top-right placement at the default size, fitted to the
 // current viewport. Reads `window` only when called (inside an effect).
 function computeInitialGeom() {
@@ -155,6 +161,12 @@ export default function AiChatWindow() {
   const { data: messageRows, isLoading: messagesLoading } =
     useAiChatMessagesQuery(activeChatId ?? undefined);
 
+  // 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);
+
   // The page the user is currently viewing. AiChatWindow lives in a pathless
   // parent layout route, so useParams() can't see :pageSlug. Match the full
   // pathname against the authenticated page route instead so "the current page"
@@ -294,21 +306,6 @@ export default function AiChatWindow() {
     return 0;
   }, [activeChatId, messageRows]);
 
-  // The model's context-window size (badge denominator), read from the most
-  // recent assistant row that carries it. Admin-configured in AI settings and
-  // stamped onto the turn server-side, so it travels with the message metadata —
-  // no client-side model resolution, and it survives public shares / per-role
-  // models automatically. 0 (no limit configured, or older rows) → the badge
-  // hides the denominator and shows only the current context size.
-  const maxContextTokens = useMemo(() => {
-    if (!activeChatId || !messageRows) return 0;
-    for (let i = messageRows.length - 1; i >= 0; i--) {
-      const max = messageRows[i].metadata?.maxContextTokens;
-      if (typeof max === "number" && max > 0) return max;
-    }
-    return 0;
-  }, [activeChatId, messageRows]);
-
   // On (re)open, settle the geometry before paint (useLayoutEffect → no
   // first-frame jump): compute an initial top-right placement the first time,
   // and re-clamp an existing geometry to the current viewport on later opens
@@ -498,14 +495,23 @@ export default function AiChatWindow() {
         )}
 
         <div style={{ flex: 1, display: "flex", justifyContent: "center" }}>
-          {/* Context badge: always "current / max" context size (or just current
-              when no model limit is configured). It no longer flips to a live
-              per-turn generation counter mid-stream — that live feedback lives in
-              the chat body's "Thinking · N tokens" block. */}
-          <ContextBadge
-            contextTokens={contextTokens}
-            maxContextTokens={maxContextTokens}
-          />
+          {/* While a turn streams, show the LIVE turn-token count (ticks ~8 Hz);
+              once it finishes, fall back to the persisted context size. Require
+              > 0 so the very first emit (an empty tail message, count 0) does not
+              flash a "0" badge before any token streams in (#151 review). */}
+          {liveTurnTokens !== null && liveTurnTokens > 0 ? (
+            <Tooltip label={t("Tokens generated this turn")} withArrow>
+              <span className={classes.badge}>
+                {formatTokens(liveTurnTokens)}
+              </span>
+            </Tooltip>
+          ) : contextTokens > 0 ? (
+            <Tooltip label={t("Current context size")} withArrow>
+              <span className={classes.badge}>
+                {formatTokens(contextTokens)}
+              </span>
+            </Tooltip>
+          ) : null}
         </div>
 
         <div style={{ display: "flex", alignItems: "center", gap: 1 }}>
@@ -628,6 +634,7 @@ export default function AiChatWindow() {
               assistantName={currentRole?.name}
               onTurnFinished={onTurnFinished}
               onServerChatId={onServerChatId}
+              onLiveTurnTokens={setLiveTurnTokens}
             />
           )}
         </div>

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

@@ -20,6 +20,7 @@ import {
 } from "@/features/ai-chat/utils/role-launch.ts";
 import { describeChatError } from "@/features/ai-chat/utils/error-message.ts";
 import { extractServerChatId } from "@/features/ai-chat/utils/adopt-chat-id.ts";
+import { liveTurnTokens } from "@/features/ai-chat/utils/count-stream-tokens.ts";
 import {
   dequeue,
   enqueueMessage,
@@ -66,6 +67,12 @@ interface ChatThreadProps {
    *  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;
 }
 
 /**
@@ -110,6 +117,7 @@ export default function ChatThread({
   assistantName,
   onTurnFinished,
   onServerChatId,
+  onLiveTurnTokens,
 }: ChatThreadProps) {
   const { t } = useTranslation();
 
@@ -320,6 +328,53 @@ 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;
 
+  // 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
+  // streaming, authoritative once a step reports usage) is the live figure. When
+  // the turn ends we emit a final exact value, then `null` so the parent reverts
+  // the badge to the persisted context size.
+  const lastEmitRef = useRef(0);
+  const emitTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+  useEffect(() => {
+    if (!onLiveTurnTokens) return;
+    if (!isStreaming) {
+      // Turn ended (or never started): clear any pending throttle and revert.
+      if (emitTimerRef.current) {
+        clearTimeout(emitTimerRef.current);
+        emitTimerRef.current = null;
+      }
+      lastEmitRef.current = 0;
+      onLiveTurnTokens(null);
+      return;
+    }
+    const tail = messages[messages.length - 1];
+    const live = tail?.role === "assistant" ? liveTurnTokens(tail) : null;
+    const total = live ? live.reasoning + live.output : 0;
+    const now = Date.now();
+    const MIN_INTERVAL = 120; // ms (~8 Hz)
+    const elapsed = now - lastEmitRef.current;
+    if (elapsed >= MIN_INTERVAL) {
+      lastEmitRef.current = now;
+      onLiveTurnTokens(total);
+    } else if (!emitTimerRef.current) {
+      // Schedule a trailing emit so the FINAL value of a burst is not dropped.
+      emitTimerRef.current = setTimeout(() => {
+        emitTimerRef.current = null;
+        lastEmitRef.current = Date.now();
+        onLiveTurnTokens(total);
+      }, MIN_INTERVAL - elapsed);
+    }
+  }, [messages, isStreaming, onLiveTurnTokens]);
+
+  // Clear any pending throttle timer on unmount (chat switch via `key`) so a
+  // trailing emit can't fire into a torn-down thread's parent.
+  useEffect(() => {
+    return () => {
+      if (emitTimerRef.current) clearTimeout(emitTimerRef.current);
+    };
+  }, []);
+
   // A role was picked with autoStart=false: the role is bound but NOTHING was
   // sent, so chatId stays null and the empty state would keep showing the cards.
   // This flag hides the cards and reveals the composer (with the role indicated)

apps/client/src/features/ai-chat/components/context-badge.test.tsx

@@ -1,69 +0,0 @@
-import { describe, it, expect } from "vitest";
-import { render, screen, fireEvent } from "@testing-library/react";
-import { MantineProvider } from "@mantine/core";
-import { ContextBadge, formatTokens } from "./context-badge";
-
-// matchMedia (read by MantineProvider) is stubbed globally in vitest.setup.ts.
-// Without an I18nextProvider, `t(key)` returns the key verbatim, so tooltip
-// labels assert against their English source strings.
-
-function renderBadge(props: {
-  contextTokens: number;
-  maxContextTokens?: number;
-}) {
-  return render(
-    <MantineProvider>
-      <ContextBadge {...props} />
-    </MantineProvider>,
-  );
-}
-
-describe("formatTokens", () => {
-  it("formats with k / M suffixes", () => {
-    expect(formatTokens(572)).toBe("572");
-    expect(formatTokens(200_000)).toBe("200.0k");
-    expect(formatTokens(1_500_000)).toBe("1.5M");
-  });
-});
-
-describe("ContextBadge", () => {
-  it("shows `current / max` when a limit is configured", () => {
-    renderBadge({ contextTokens: 572, maxContextTokens: 200_000 });
-    expect(screen.getByText("572 / 200.0k")).toBeDefined();
-  });
-
-  it("shows only the current size when no limit is configured", () => {
-    renderBadge({ contextTokens: 572, maxContextTokens: 0 });
-    expect(screen.getByText("572")).toBeDefined();
-    // No denominator rendered.
-    expect(screen.queryByText(/\//)).toBeNull();
-  });
-
-  it("treats an undefined limit as no limit", () => {
-    renderBadge({ contextTokens: 1234 });
-    expect(screen.getByText("1.2k")).toBeDefined();
-    expect(screen.queryByText(/\//)).toBeNull();
-  });
-
-  it("renders nothing until there is a current context size", () => {
-    const { container } = renderBadge({
-      contextTokens: 0,
-      maxContextTokens: 200_000,
-    });
-    expect(container.querySelector("span")).toBeNull();
-  });
-
-  it("never flips to a live per-turn counter (no live mode); shows context as-is even above max", () => {
-    // `current > max` (estimate drift / smaller-model role) is shown unclamped.
-    renderBadge({ contextTokens: 210_000, maxContextTokens: 200_000 });
-    expect(screen.getByText("210.0k / 200.0k")).toBeDefined();
-  });
-
-  it("exposes the limit tooltip label on hover", async () => {
-    renderBadge({ contextTokens: 572, maxContextTokens: 200_000 });
-    fireEvent.mouseEnter(screen.getByText("572 / 200.0k"));
-    expect(
-      await screen.findByText("Context size / model limit"),
-    ).toBeDefined();
-  });
-});

apps/client/src/features/ai-chat/components/context-badge.tsx

@@ -1,61 +0,0 @@
-import { Tooltip } from "@mantine/core";
-import { useTranslation } from "react-i18next";
-import classes from "@/features/ai-chat/components/ai-chat-window.module.css";
-
-/** Compact token formatter: 1.2M / 3.4k / 950. */
-export function formatTokens(n: number): string {
-  if (n >= 1_000_000) return `${(n / 1_000_000).toFixed(1)}M`;
-  if (n >= 1_000) return `${(n / 1_000).toFixed(1)}k`;
-  return String(n);
-}
-
-interface ContextBadgeProps {
-  // Current context size for the active chat (tokens occupied in the model's
-  // window). 0 = unknown → nothing is rendered.
-  contextTokens: number;
-  // The model's context-window size (tokens), from AI settings. 0/undefined =
-  // no limit known → only the current size is shown (no denominator).
-  maxContextTokens?: number;
-}
-
-/**
- * Header badge that ALWAYS shows the current context size, and — when the model's
- * context-window size is configured — appends "/ max" so the badge reads
- * "current / max" (e.g. `572 / 200k`). This is a single, stable meaning: unlike
- * the previous design it never flips to a live per-turn generation counter while
- * streaming (that live feedback lives in the chat body's "Thinking · N tokens").
- *
- * No limit configured (or older history rows without it) → the denominator is
- * hidden and the badge shows the current size only, matching the prior at-rest
- * behaviour. `context > max` (estimate drift, or a role on a smaller model) is
- * shown as-is, without clamping.
- */
-export function ContextBadge({
-  contextTokens,
-  maxContextTokens,
-}: ContextBadgeProps) {
-  const { t } = useTranslation();
-
-  // Nothing to show until the first persisted context figure exists.
-  if (!(contextTokens > 0)) return null;
-
-  const hasMax = typeof maxContextTokens === "number" && maxContextTokens > 0;
-  const label = hasMax
-    ? `${formatTokens(contextTokens)} / ${formatTokens(maxContextTokens)}`
-    : formatTokens(contextTokens);
-
-  return (
-    <Tooltip
-      label={
-        hasMax
-          ? t("Context size / model limit")
-          : t("Current context size")
-      }
-      withArrow
-    >
-      <span className={classes.badge}>{label}</span>
-    </Tooltip>
-  );
-}
-
-export default ContextBadge;

apps/client/src/features/ai-chat/types/ai-chat.types.ts

@@ -113,14 +113,9 @@ export interface IAiChatMessageRow {
     };
     // Current context size for the turn = final-step (input+output) tokens, i.e.
     // how much the conversation occupies in the model's context window after this
-    // turn. Distinct from `usage` (legacy cumulative totalUsage). Shown as the
-    // numerator of the floating window's "current / max" header badge.
+    // turn. Distinct from `usage` (legacy cumulative totalUsage). Shown in the
+    // floating window's header badge.
     contextTokens?: number;
-    // The model's context-window size (tokens), admin-configured in AI settings
-    // and stamped onto the turn server-side. The denominator of the header badge.
-    // Absent/0 (older rows, or no limit configured) → the badge hides the
-    // denominator and shows only the current context size (`contextTokens`).
-    maxContextTokens?: number;
     // Set on an assistant row whose turn ended in a provider/stream error; the
     // raw provider error text (e.g. "402: ...") for inline display in the thread.
     error?: string;

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

@@ -1,5 +1,17 @@
 import { describe, expect, it } from "vitest";
-import { estimateTokens } from "@/features/ai-chat/utils/count-stream-tokens.ts";
+import type { UIMessage } from "@ai-sdk/react";
+import {
+  estimateTokens,
+  liveTurnTokens,
+} from "@/features/ai-chat/utils/count-stream-tokens.ts";
+
+const msg = (parts: unknown[], metadata?: unknown): UIMessage =>
+  ({
+    id: Math.random().toString(),
+    role: "assistant",
+    parts,
+    metadata,
+  }) as UIMessage;
 
 describe("estimateTokens", () => {
   it("returns 0 for the empty string", () => {
@@ -13,3 +25,147 @@ describe("estimateTokens", () => {
     expect(estimateTokens("12345678")).toBe(2);
   });
 });
+
+describe("liveTurnTokens — estimate path", () => {
+  it("is all zeros for an undefined message", () => {
+    expect(liveTurnTokens(undefined)).toEqual({
+      reasoning: 0,
+      output: 0,
+      authoritative: false,
+    });
+  });
+
+  it("is all zeros for a parts-less message", () => {
+    expect(liveTurnTokens({ id: "x", role: "assistant" } as UIMessage)).toEqual({
+      reasoning: 0,
+      output: 0,
+      authoritative: false,
+    });
+  });
+
+  it("estimates output from text parts", () => {
+    // 8 chars -> 2 tokens.
+    const r = liveTurnTokens(msg([{ type: "text", text: "12345678" }]));
+    expect(r).toEqual({ reasoning: 0, output: 2, authoritative: false });
+  });
+
+  it("estimates reasoning from reasoning parts (kept separate from output)", () => {
+    const r = liveTurnTokens(
+      msg([
+        { type: "reasoning", text: "12345678" },
+        { type: "text", text: "abcd" },
+      ]),
+    );
+    expect(r).toEqual({ reasoning: 2, output: 1, authoritative: false });
+  });
+
+  it("accumulates across multiple text + reasoning parts (multi-step)", () => {
+    const r = liveTurnTokens(
+      msg([
+        { type: "reasoning", text: "abcd" }, // 1
+        { type: "text", text: "abcd" }, // 1
+        { type: "tool-getPage", state: "output-available" }, // ignored
+        { type: "reasoning", text: "abcd" }, // 1
+        { type: "text", text: "abcdefgh" }, // 2
+      ]),
+    );
+    expect(r).toEqual({ reasoning: 2, output: 3, authoritative: false });
+  });
+
+  it("ignores non text/reasoning parts (tools, step-start)", () => {
+    const r = liveTurnTokens(
+      msg([
+        { type: "step-start" },
+        { type: "tool-getPage", state: "input-available" },
+      ]),
+    );
+    expect(r).toEqual({ reasoning: 0, output: 0, authoritative: false });
+  });
+});
+
+describe("liveTurnTokens — authoritative path", () => {
+  it("returns authoritative usage verbatim, splitting reasoning out of output", () => {
+    // outputTokens INCLUDES reasoning in the AI SDK shape -> answer = 100 - 30.
+    const r = liveTurnTokens(
+      msg([{ type: "text", text: "estimate would be tiny" }], {
+        usage: { inputTokens: 500, outputTokens: 100, reasoningTokens: 30 },
+      }),
+    );
+    expect(r).toEqual({ reasoning: 30, output: 70, authoritative: true });
+  });
+
+  it("treats missing reasoningTokens as 0 and keeps full output", () => {
+    const r = liveTurnTokens(
+      msg([{ type: "text", text: "x" }], {
+        usage: { inputTokens: 10, outputTokens: 42 },
+      }),
+    );
+    expect(r).toEqual({ reasoning: 0, output: 42, authoritative: true });
+  });
+
+  it("never returns a negative output when reasoning exceeds reported output", () => {
+    const r = liveTurnTokens(
+      msg([], { usage: { outputTokens: 10, reasoningTokens: 40 } }),
+    );
+    expect(r).toEqual({ reasoning: 40, output: 0, authoritative: true });
+  });
+
+  it("falls back to the estimate when metadata has no usage object", () => {
+    const r = liveTurnTokens(
+      msg([{ type: "text", text: "abcd" }], { chatId: "c1" }),
+    );
+    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

@@ -1,16 +1,18 @@
+import type { UIMessage } from "@ai-sdk/react";
+
 /**
- * Live token ESTIMATION for a streaming AI-chat turn.
+ * Live token counting for a streaming AI-chat turn — split into REASONING
+ * (thinking) and OUTPUT (answer) tokens, mirroring how Claude Code shows
+ * `Thinking… · 60 tokens` next to its thinking indicator.
  *
  * No provider streams exact per-token usage mid-stream, so the live number is a
- * CLIENT ESTIMATE (chars/≈4 heuristic). It powers the chat body's
- * `Thinking… · N tokens` indicator (see `ReasoningBlock`), which reconciles to
- * the authoritative server usage once it lands. Pure + unit-testable: it never
- * runs a real BPE tokenizer (that would be O(n²) on the hot path, bloat the
+ * CLIENT ESTIMATE (chars/≈4 heuristic) that is reconciled to AUTHORITATIVE usage
+ * once the server attaches it on a step/turn boundary (see the server's
+ * `chatStreamMetadata` + the client's read of `message.metadata.usage`). When
+ * authoritative usage is present we return it verbatim (the number "jumps to
+ * exact"); otherwise we return the running estimate. Pure + unit-testable: it
+ * never runs a real BPE tokenizer (that would be O(n²) on the hot path, bloat the
  * bundle, and be wrong for Gemini/Ollama anyway).
- *
- * The former header-badge `liveTurnTokens()` split was removed with #189 (the
- * header badge now shows the stable "current / max" context size, not a live
- * per-turn counter); the live feedback remains in `ReasoningBlock`.
  */
 
 /**
@@ -22,3 +24,90 @@ export function estimateTokens(text: string): number {
   if (!text) return 0;
   return Math.ceil(text.length / 4);
 }
+
+/** Authoritative per-step/turn usage the server attaches to message metadata. */
+export interface AuthoritativeUsage {
+  inputTokens?: number;
+  outputTokens?: number;
+  totalTokens?: number;
+  reasoningTokens?: number;
+}
+
+/** Live token split for a turn's tail (streaming) assistant message. */
+export interface LiveTurnTokens {
+  /** Thinking/reasoning tokens (estimate, or authoritative when available). */
+  reasoning: number;
+  /** Answer/output tokens (estimate, or authoritative when available). */
+  output: number;
+  /** True when the numbers come from authoritative server usage, not estimate. */
+  authoritative: boolean;
+}
+
+/** Read the authoritative usage off a UIMessage's metadata, if the server set it. */
+function metadataUsage(message: UIMessage): AuthoritativeUsage | undefined {
+  const meta = message?.metadata as
+    | { usage?: AuthoritativeUsage }
+    | undefined;
+  const usage = meta?.usage;
+  if (!usage || typeof usage !== "object") return undefined;
+  return usage;
+}
+
+/**
+ * Token split for the given (streaming) assistant message.
+ *
+ * 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 (`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 };
+
+  // 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") {
+      estReasoning += estimateTokens((part as { text?: string }).text ?? "");
+    } else if (part.type === "text") {
+      estOutput += estimateTokens((part as { text?: string }).text ?? "");
+    }
+  }
+
+  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/workspace/components/settings/components/ai-provider-settings.tsx

@@ -7,7 +7,6 @@ import {
   Button,
   Group,
   Modal,
-  NumberInput,
   Paper,
   PasswordInput,
   Select,
@@ -86,9 +85,6 @@ const formSchema = z.object({
   chatModel: z.string(),
   // Chat provider implementation (reasoning surfacing). Default openai-compatible.
   chatApiStyle: z.enum(["openai-compatible", "openai"]),
-  // Model context-window size (tokens) shown as the chat header badge's "max".
-  // Empty string = no limit (NumberInput emits "" when cleared).
-  chatContextWindow: z.union([z.number(), z.literal("")]),
   // Cheap model id for the anonymous public-share assistant; empty = use chatModel.
   publicShareChatModel: z.string(),
   // Agent-role id whose persona the public-share assistant adopts; empty =
@@ -316,7 +312,6 @@ export default function AiProviderSettings() {
     initialValues: {
       chatModel: "",
       chatApiStyle: "openai-compatible" as ChatApiStyle,
-      chatContextWindow: "" as number | "",
       publicShareChatModel: "",
       publicShareAssistantRoleId: "",
       embeddingModel: "",
@@ -340,10 +335,6 @@ export default function AiProviderSettings() {
     form.setValues({
       chatModel: settings.chatModel ?? "",
       chatApiStyle: settings.chatApiStyle ?? "openai-compatible",
-      // 0/unset = no limit → show an empty field (not a literal "0").
-      chatContextWindow: settings.chatContextWindow
-        ? settings.chatContextWindow
-        : "",
       publicShareChatModel: settings.publicShareChatModel ?? "",
       publicShareAssistantRoleId: settings.publicShareAssistantRoleId ?? "",
       embeddingModel: settings.embeddingModel ?? "",
@@ -374,11 +365,6 @@ export default function AiProviderSettings() {
       driver: "openai",
       chatModel: values.chatModel,
       chatApiStyle: values.chatApiStyle,
-      // Empty → 0, which clears the limit server-side (badge shows current only).
-      chatContextWindow:
-        typeof values.chatContextWindow === "number"
-          ? values.chatContextWindow
-          : 0,
       // Cheap model id for the anonymous public-share assistant; empty falls
       // back to chatModel server-side.
       publicShareChatModel: values.publicShareChatModel,
@@ -799,22 +785,6 @@ export default function AiProviderSettings() {
           {...form.getInputProps("chatApiStyle")}
         />
 
-        <NumberInput
-          mt="sm"
-          label={t("Context window (tokens)")}
-          description={t(
-            "Shows used / total in the chat header badge; empty hides the total.",
-          )}
-          placeholder={t("e.g. 200000")}
-          min={0}
-          step={1000}
-          allowDecimal={false}
-          allowNegative={false}
-          thousandSeparator=" "
-          disabled={isLoading}
-          {...form.getInputProps("chatContextWindow")}
-        />
-
         {/* Anonymous public-share assistant: a single master toggle + an
             optional cheaper model id. Reuses this card's driver/URL/key. */}
         <Group justify="space-between" align="center" wrap="nowrap" mt="md">

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

@@ -23,9 +23,6 @@ export interface IAiSettings {
   driver?: AiDriver;
   chatModel?: string;
   chatApiStyle?: ChatApiStyle;
-  // Chat model context-window size (tokens); shown as the "max" in the chat
-  // header context badge. 0/unset = no limit (badge shows the current size only).
-  chatContextWindow?: number;
   // Cheap model id for the anonymous public-share assistant; empty = chatModel.
   publicShareChatModel?: string;
   // Agent-role id whose persona the public-share assistant adopts; empty =
@@ -60,8 +57,6 @@ export interface IAiSettingsUpdate {
   driver?: AiDriver;
   chatModel?: string;
   chatApiStyle?: ChatApiStyle;
-  // Chat model context-window size (tokens); 0 clears the limit.
-  chatContextWindow?: number;
   publicShareChatModel?: string;
   // Agent-role id whose persona the public-share assistant adopts; empty =
   // built-in locked persona.

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

@@ -292,26 +292,6 @@ describe('flushAssistant', () => {
     expect(f.metadata.contextTokens).toBe(15);
   });
 
-  it('completed: writes maxContextTokens when the model limit is > 0', () => {
-    const f = flushAssistant([toolStep], '', 'completed', {
-      contextTokens: 15,
-      maxContextTokens: 200_000,
-    });
-    expect(f.metadata.maxContextTokens).toBe(200_000);
-  });
-
-  it('omits maxContextTokens when the limit is unset or 0', () => {
-    const unset = flushAssistant([toolStep], '', 'completed', {
-      contextTokens: 15,
-    });
-    expect('maxContextTokens' in unset.metadata).toBe(false);
-    const zero = flushAssistant([toolStep], '', 'completed', {
-      contextTokens: 15,
-      maxContextTokens: 0,
-    });
-    expect('maxContextTokens' in zero.metadata).toBe(false);
-  });
-
   it('error: records the error and a derived finishReason', () => {
     const f = flushAssistant([], 'partial answer', 'error', { error: 'boom' });
     expect(f.status).toBe('error');

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

@@ -616,9 +616,6 @@ export class AiChatService implements OnModuleInit {
               contextTokens:
                 (usage?.inputTokens ?? 0) + (usage?.outputTokens ?? 0) ||
                 undefined,
-              // Admin-configured context-window size for this model (badge max).
-              // Resolved once per turn above; written to metadata only when > 0.
-              maxContextTokens: resolved?.chatContextWindow,
             }),
           );
           // Lifecycle: release the external MCP clients leased for this turn.
@@ -1226,10 +1223,6 @@ export function flushAssistant(
     finishReason?: string;
     usage?: ChatStreamUsage | StreamUsage | undefined;
     contextTokens?: number;
-    // Admin-configured context-window size (tokens) for this turn's model; the
-    // denominator of the client's "current / max" header badge. Written only
-    // when > 0 (0/unset = no limit known → the badge shows current only).
-    maxContextTokens?: number;
     error?: string;
   },
 ): AssistantFlush {
@@ -1260,9 +1253,6 @@ export function flushAssistant(
       normalizeStreamUsage(extra.usage as StreamUsage) ?? extra.usage;
   }
   if (extra?.contextTokens) metadata.contextTokens = extra.contextTokens;
-  if (extra?.maxContextTokens && extra.maxContextTokens > 0) {
-    metadata.maxContextTokens = extra.maxContextTokens;
-  }
   if (extra?.error) metadata.error = extra.error;
 
   return {

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

@@ -120,21 +120,26 @@ describe('AiChatToolsService deletePage guardrail (H4)', () => {
     const tools = await buildTools();
     const deletePage = tools.deletePage;
 
-    // The Zod input schema only allows `pageId`; parsing strips/ignores extra
-    // keys, so a permanent/force flag is never part of the validated input.
+    // inputSchema is now an AI SDK `Schema` (not a raw zod object). Its
+    // `validate` runs the same zod safeParse and forwards the STRIPPED data, so
+    // a permanent/force flag is never part of the validated input the SDK then
+    // hands to execute.
     const schema = (deletePage as unknown as { inputSchema: unknown })
       .inputSchema as {
-      parse: (v: unknown) => Record<string, unknown>;
+      validate: (
+        v: unknown,
+      ) => Promise<{ success: boolean; value?: Record<string, unknown> }>;
     };
-    const parsed = schema.parse({
+    const result = await schema.validate({
       pageId: 'page-789',
       permanentlyDelete: true,
       forceDelete: true,
     });
 
-    expect(parsed).toHaveProperty('pageId', 'page-789');
-    expect(parsed).not.toHaveProperty('permanentlyDelete');
-    expect(parsed).not.toHaveProperty('forceDelete');
+    expect(result.success).toBe(true);
+    expect(result.value).toHaveProperty('pageId', 'page-789');
+    expect(result.value).not.toHaveProperty('permanentlyDelete');
+    expect(result.value).not.toHaveProperty('forceDelete');
   });
 });
 
@@ -207,21 +212,25 @@ describe('AiChatToolsService expanded toolset guardrails', () => {
     const tools = await buildTools();
     const transformPage = tools.transformPage;
 
-    // The Zod input schema only allows pageId/transformJs/dryRun; parsing
-    // strips unknown keys, so deleteComments can never reach the client.
+    // inputSchema is now an AI SDK `Schema`; its `validate` runs the same zod
+    // safeParse, which only allows pageId/transformJs/dryRun and strips unknown
+    // keys — so deleteComments can never reach the client.
     const schema = (transformPage as unknown as { inputSchema: unknown })
       .inputSchema as {
-      parse: (v: unknown) => Record<string, unknown>;
+      validate: (
+        v: unknown,
+      ) => Promise<{ success: boolean; value?: Record<string, unknown> }>;
     };
-    const parsed = schema.parse({
+    const result = await schema.validate({
       pageId: 'p',
       transformJs: '(d)=>d',
       dryRun: true,
       deleteComments: true,
     });
 
-    expect(parsed).toHaveProperty('pageId', 'p');
-    expect(parsed).not.toHaveProperty('deleteComments');
+    expect(result.success).toBe(true);
+    expect(result.value).toHaveProperty('pageId', 'p');
+    expect(result.value).not.toHaveProperty('deleteComments');
   });
 });
 

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

@@ -15,6 +15,7 @@ import {
 } from './docmost-client.loader';
 import { resolveCurrentPageResult } from './current-page.util';
 import { parseNodeArg } from './parse-node-arg';
+import { modelFriendlyInput } from './model-friendly-input';
 
 /**
  * Per-user, per-request adapter that exposes Docmost READ operations to the
@@ -102,9 +103,9 @@ export class AiChatToolsService {
     ): Tool =>
       tool({
         description: spec.description,
-        inputSchema: spec.buildShape
-          ? z.object(spec.buildShape(z) as z.ZodRawShape)
-          : z.object({}),
+        inputSchema: modelFriendlyInput(
+          spec.buildShape ? (spec.buildShape(z) as z.ZodRawShape) : {},
+        ),
         execute,
       });
 
@@ -118,7 +119,7 @@ export class AiChatToolsService {
           'and entities), not a full sentence. If the first results look weak ' +
           'or incomplete, search again with different wording or synonyms ' +
           'before answering.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           query: z.string().describe('The search query.'),
           limit: z
             .number()
@@ -227,7 +228,7 @@ export class AiChatToolsService {
           '"the current page", or "here" refers to. Returns the page id and title, ' +
           'or null if the user is not currently on a page. Call this first whenever ' +
           'the user refers to the current page without giving an explicit id.',
-        inputSchema: z.object({}),
+        inputSchema: modelFriendlyInput({}),
         execute: async () => resolveCurrentPageResult(openedPage),
       }),
 
@@ -235,7 +236,7 @@ export class AiChatToolsService {
         description:
           'Fetch a single page as Markdown by its page id. Returns the page ' +
           'title and its Markdown content.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id (or slugId) of the page.'),
         }),
         execute: async ({ pageId }) => {
@@ -259,7 +260,7 @@ export class AiChatToolsService {
           'Create a new page with a Markdown body in a space, optionally under ' +
           'a parent page. Returns the new page id and title. Reversible: a page ' +
           'can be moved to trash later.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           title: z.string().describe('The title of the new page.'),
           content: z
             .string()
@@ -294,7 +295,7 @@ export class AiChatToolsService {
         description:
           "Replace a page's body with new Markdown content (and optionally its " +
           'title). Reversible: the previous version is kept in page history.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to update.'),
           content: z.string().describe('The new page body as Markdown.'),
           title: z
@@ -316,7 +317,7 @@ export class AiChatToolsService {
         description:
           "Rename a page (change its title only; the body is untouched). " +
           'Reversible: rename back at any time.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to rename.'),
           title: z.string().describe('The new title.'),
         }),
@@ -331,7 +332,7 @@ export class AiChatToolsService {
         description:
           'Move a page under a new parent page, or to the space root when no ' +
           'parent is given. Reversible: move it back at any time.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to move.'),
           parentPageId: z
             .string()
@@ -353,7 +354,7 @@ export class AiChatToolsService {
         description:
           'Move a page to the trash (SOFT delete only — fully reversible; the ' +
           'page can be restored from trash). This NEVER permanently deletes.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to move to trash.'),
         }),
         // GUARDRAIL (§14 H4): the only field ever passed to the client is
@@ -379,7 +380,7 @@ export class AiChatToolsService {
           '"selection not found" error, retry with a corrected EXACT selection ' +
           'copied verbatim from a single paragraph/block. Reversible via the ' +
           'comment UI.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to comment on.'),
           content: z.string().describe('The comment body as Markdown.'),
           selection: z
@@ -428,7 +429,7 @@ export class AiChatToolsService {
         description:
           'Resolve or reopen a top-level comment thread (reversible — toggle ' +
           'the resolved flag). Only top-level comments can be resolved.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           commentId: z
             .string()
             .describe('The id of the top-level comment to resolve/reopen.'),
@@ -460,7 +461,7 @@ export class AiChatToolsService {
           'List the most recent pages, optionally scoped to a single space. ' +
           'Returns a bounded list (default 50, max 100). Pass tree:true (with ' +
           "spaceId) to instead get the space's full page hierarchy as a nested tree.",
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           spaceId: z
             .string()
             .optional()
@@ -488,7 +489,7 @@ export class AiChatToolsService {
           'List sidebar pages for a space. With no pageId, returns the ' +
           "space's ROOT pages; with a pageId, returns that page's direct " +
           'CHILDREN.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           spaceId: z.string().describe('The id of the space.'),
           pageId: z
             .string()
@@ -520,7 +521,7 @@ export class AiChatToolsService {
         description:
           'Read a table as a matrix of cell texts (plus a parallel cellIds ' +
           'matrix so cells can be addressed for rich edits).',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page.'),
           tableRef: z
             .string()
@@ -536,7 +537,7 @@ export class AiChatToolsService {
       listComments: tool({
         description:
           'List all comments on a page (content as Markdown).',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page.'),
         }),
         execute: async ({ pageId }) => await client.listComments(pageId),
@@ -544,7 +545,7 @@ export class AiChatToolsService {
 
       getComment: tool({
         description: 'Fetch a single comment by id (content as Markdown).',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           commentId: z.string().describe('The id of the comment.'),
         }),
         execute: async ({ commentId }) => await client.getComment(commentId),
@@ -554,7 +555,7 @@ export class AiChatToolsService {
         description:
           'Find new comments across a space (optionally scoped to a subtree) ' +
           'created after a given timestamp.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           spaceId: z.string().describe('The id of the space to scan.'),
           since: z
             .string()
@@ -586,7 +587,7 @@ export class AiChatToolsService {
         description:
           'Fetch a single page-history version including its lossless ' +
           'ProseMirror content.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           historyId: z.string().describe('The id of the history version.'),
         }),
         execute: async ({ historyId }) =>
@@ -604,7 +605,7 @@ export class AiChatToolsService {
           'Export a page to a single self-contained Docmost-flavoured ' +
           'Markdown file (meta + body + comment threads). Lossless round-trip ' +
           'with importPageMarkdown.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to export.'),
         }),
         execute: async ({ pageId }) => {
@@ -630,7 +631,7 @@ export class AiChatToolsService {
           '{"type":"text","text":"x","marks":[{"type":"bold"}]}. The node arg ' +
           'may be a JSON object or a JSON string (both accepted). Reversible: ' +
           'the previous version is kept in page history.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page.'),
           nodeId: z
             .string()
@@ -663,7 +664,7 @@ export class AiChatToolsService {
           '{"type":"text","text":"x","marks":[{"type":"bold"}]}. The node arg ' +
           'may be a JSON object or a JSON string (both accepted). Reversible ' +
           'via page history.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page.'),
           node: z
             .any()
@@ -722,7 +723,7 @@ export class AiChatToolsService {
           'object or a JSON string (both accepted). Omit content for a ' +
           'title-only update. Reversible: the previous version is kept in page ' +
           'history.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to update.'),
           content: z
             .any()
@@ -753,7 +754,7 @@ export class AiChatToolsService {
         description:
           'Insert a row of plain-text cells into a table. Reversible via ' +
           'page history.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page.'),
           tableRef: z
             .string()
@@ -772,7 +773,7 @@ export class AiChatToolsService {
       tableDeleteRow: tool({
         description:
           'Delete a table row at a 0-based index. Reversible via page history.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page.'),
           tableRef: z
             .string()
@@ -787,7 +788,7 @@ export class AiChatToolsService {
         description:
           'Set the plain-text content of a table cell at [row, col] (0-based). ' +
           'Reversible via page history.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page.'),
           tableRef: z
             .string()
@@ -817,7 +818,7 @@ export class AiChatToolsService {
           'Make a page PUBLICLY accessible and return its public URL. ' +
           'Reversible via unsharePage. Only share when the user explicitly ' +
           'asked, since this exposes the page to anyone with the link.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to share.'),
           searchIndexing: z
             .boolean()
@@ -844,7 +845,7 @@ export class AiChatToolsService {
           "page's ProseMirror document for complex/scripted rewrites. dryRun " +
           '(default true) previews a diff WITHOUT writing; set dryRun:false to ' +
           'apply. Reversible: applying creates a new page-history snapshot.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z.string().describe('The id of the page to transform.'),
           transformJs: z
             .string()

apps/server/src/core/ai-chat/tools/model-friendly-input.spec.ts

@@ -0,0 +1,112 @@
+import { z } from 'zod';
+import { modelFriendlyInput } from './model-friendly-input';
+
+/**
+ * Unit tests for the model-friendly input wrapper (issue #190): validation
+ * failures must report a human-readable, parameter-naming message (not the raw
+ * zod text), successful validation must strip unknown keys (preserving the
+ * strip guardrails), and the JSON schema handed to the model must keep the
+ * required/optional contract and field descriptions intact.
+ */
+describe('modelFriendlyInput', () => {
+  // A representative shape: a required id + description, plus an optional field.
+  const shape = {
+    pageId: z.string().describe('The id of the page to comment on.'),
+    content: z.string(),
+    limit: z.number().int().optional(),
+  };
+
+  // The AI SDK `Schema` exposes a `validate` callback and a `jsonSchema` field;
+  // type them loosely for the test.
+  type SchemaLike = {
+    validate?: (
+      v: unknown,
+    ) =>
+      | { success: boolean; value?: Record<string, unknown>; error?: Error }
+      | PromiseLike<{
+          success: boolean;
+          value?: Record<string, unknown>;
+          error?: Error;
+        }>;
+    jsonSchema: unknown;
+  };
+
+  it('reports a model-friendly error naming the missing REQUIRED param + retry hint', async () => {
+    const schema = modelFriendlyInput(shape) as unknown as SchemaLike;
+    // Drop the required `pageId` (the parallel-batch failure mode).
+    const result = await schema.validate!({ content: 'hi' });
+
+    expect(result.success).toBe(false);
+    const message = result.error?.message ?? '';
+    // Names the offending parameter by name.
+    expect(message).toContain('pageId');
+    // Carries the fixed actionable retry hint.
+    expect(message).toContain('Include every REQUIRED parameter and retry');
+    expect(message).toContain('do not drop ids like "pageId"');
+    // It must NOT be the bare raw zod text alone — our wrapper prefix is present.
+    expect(message).toContain('Invalid tool input');
+  });
+
+  it('accepts valid input and STRIPS unknown keys (keeps declared ones)', async () => {
+    const schema = modelFriendlyInput(shape) as unknown as SchemaLike;
+    const result = await schema.validate!({
+      pageId: 'p-1',
+      content: 'hello',
+      // An extra unknown key a (compromised) model might emit.
+      permanentlyDelete: true,
+    });
+
+    expect(result.success).toBe(true);
+    expect(result.value).toEqual({ pageId: 'p-1', content: 'hello' });
+    expect(result.value).not.toHaveProperty('permanentlyDelete');
+  });
+
+  it('produces a draft-07 JSON schema that preserves required + descriptions', async () => {
+    const schema = modelFriendlyInput(shape) as unknown as SchemaLike;
+    // jsonSchema may be a value or a promise; await either way.
+    const json = (await Promise.resolve(schema.jsonSchema)) as {
+      required?: string[];
+      properties?: Record<string, { description?: string }>;
+    };
+
+    // Required contract preserved: pageId + content required, limit optional.
+    expect(json.required).toEqual(expect.arrayContaining(['pageId', 'content']));
+    expect(json.required).not.toContain('limit');
+    // Field description preserved.
+    expect(json.properties?.pageId?.description).toBe(
+      'The id of the page to comment on.',
+    );
+  });
+
+  it('de-duplicates a parameter that produces MULTIPLE issues on the same path', async () => {
+    // A single field can fail several zod checks at once (here min-length AND a
+    // regex), yielding two issues with the SAME path. The friendly message must
+    // name that parameter only once (the `seen` dedup branch).
+    const multiIssueShape = {
+      code: z
+        .string()
+        .min(5)
+        .regex(/^[0-9]+$/),
+    };
+    const schema = modelFriendlyInput(
+      multiIssueShape,
+    ) as unknown as SchemaLike;
+    // "ab" violates BOTH the min(5) and the digit-only regex.
+    const result = await schema.validate!({ code: 'ab' });
+
+    expect(result.success).toBe(false);
+    const message = result.error?.message ?? '';
+    // The parameter name appears exactly once despite two underlying issues.
+    const occurrences = message.split('parameter "code"').length - 1;
+    expect(occurrences).toBe(1);
+  });
+
+  it('handles a root-level type error with a "(root)" parameter name', async () => {
+    const schema = modelFriendlyInput(shape) as unknown as SchemaLike;
+    // Passing a non-object yields an issue with an empty path.
+    const result = await schema.validate!('not an object');
+
+    expect(result.success).toBe(false);
+    expect(result.error?.message).toContain('(root)');
+  });
+});

apps/server/src/core/ai-chat/tools/model-friendly-input.ts

@@ -0,0 +1,72 @@
+import { jsonSchema, type JSONSchema7, type Schema } from 'ai';
+import { z } from 'zod';
+
+// Centralized input-schema wrapper for in-app AI tools. The JSON schema handed
+// to the model is derived from the same zod shape (so `required`/`description`/
+// constraints are unchanged), but validation failures are reported with a
+// human-readable message that NAMES the offending parameter(s) and asks the
+// model to retry with every required field — instead of the raw zod text. This
+// matters for parallel tool-call batches where the model tends to drop a
+// repeated id like `pageId`.
+
+// Fixed, actionable hint appended to every validation error. Kept as a constant
+// so the message stays deterministic and the spec can assert on it verbatim.
+const RETRY_HINT =
+  'Include every REQUIRED parameter and retry; when issuing parallel tool ' +
+  'calls, do not drop ids like "pageId".';
+
+/**
+ * Turn a zod validation error into a concise, model-friendly message that names
+ * each offending parameter (by its dotted path; the root object is "(root)"),
+ * gives a short reason, and ends with the fixed retry hint. Repeated parameter
+ * names are de-duplicated and the output is deterministic.
+ */
+export function formatIssues(error: z.ZodError): string {
+  const seen = new Set<string>();
+  const parts: string[] = [];
+  for (const issue of error.issues) {
+    const name =
+      Array.isArray(issue.path) && issue.path.length > 0
+        ? issue.path.join('.')
+        : '(root)';
+    if (seen.has(name)) continue;
+    seen.add(name);
+    // Prefer zod's own message (e.g. "Invalid input: expected string, received
+    // undefined"); fall back to a generic reason when it is missing.
+    const reason = issue.message ? issue.message : 'missing or invalid';
+    parts.push(`parameter "${name}": ${reason}`);
+  }
+  const summary = parts.length > 0 ? parts.join('; ') : 'invalid tool input';
+  return `Invalid tool input — ${summary}. ${RETRY_HINT}`;
+}
+
+/**
+ * Build an AI SDK `Schema` from a zod raw shape. The JSON schema exposed to the
+ * model is derived from the zod object (preserving `required`, `description`,
+ * and field constraints), so the required/optional contract is UNCHANGED. On a
+ * validation failure we return a model-friendly error (see `formatIssues`); on
+ * success we return the PARSED data, which has unknown keys stripped by zod —
+ * this preserves the existing strip guardrails (e.g. deletePage never forwards
+ * permanentlyDelete/forceDelete; transformPage never forwards deleteComments).
+ */
+export function modelFriendlyInput<Shape extends z.ZodRawShape>(
+  shape: Shape,
+): Schema<z.infer<z.ZodObject<Shape>>> {
+  const object = z.object(shape);
+  // draft-07 JSON schema for the model (keeps required/description/constraints).
+  const schema = z.toJSONSchema(object, { target: 'draft-7' }) as JSONSchema7;
+  return jsonSchema<z.infer<typeof object>>(schema, {
+    validate: (value: unknown) => {
+      const result = object.safeParse(value);
+      if (result.success) {
+        // Return the PARSED (unknown-key-stripped) data so the SDK forwards a
+        // clean object to execute — preserves the existing strip guardrails.
+        return { success: true as const, value: result.data };
+      }
+      return {
+        success: false as const,
+        error: new Error(formatIssues(result.error)),
+      };
+    },
+  });
+}

apps/server/src/core/ai-chat/tools/public-share-chat-tools.service.ts

@@ -5,6 +5,7 @@ import { ShareService } from '../../share/share.service';
 import { SearchService } from '../../search/search.service';
 import { PageRepo } from '@docmost/db/repos/page/page.repo';
 import { jsonToMarkdown } from '../../../collaboration/collaboration.util';
+import { modelFriendlyInput } from './model-friendly-input';
 
 /**
  * Isolated, READ-ONLY toolset for the ANONYMOUS public-share assistant.
@@ -52,7 +53,7 @@ export class PublicShareChatToolsService {
           '(key terms and entities), not a full sentence. If the first ' +
           'results look weak, search again with different wording before ' +
           'answering. Only pages inside this share are ever returned.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           query: z.string().describe('The search query.'),
           limit: z
             .number()
@@ -87,7 +88,7 @@ export class PublicShareChatToolsService {
           'Markdown, by its page id. Returns the page title and its Markdown ' +
           'content. Only pages inside this share can be read; reading any ' +
           'other page fails.',
-        inputSchema: z.object({
+        inputSchema: modelFriendlyInput({
           pageId: z
             .string()
             .describe('The id (or slugId) of a page within this share.'),
@@ -142,7 +143,7 @@ export class PublicShareChatToolsService {
           'List the pages (titles + ids) that make up THIS published ' +
           'documentation share, so you can orient yourself before reading or ' +
           'searching. Only pages inside this share are listed.',
-        inputSchema: z.object({}),
+        inputSchema: modelFriendlyInput({}),
         execute: async () => {
           // Reuse the same share-tree logic the public /shares/tree route uses:
           // it validates the share + workspace, excludes restricted subtrees,

apps/server/src/core/page/services/page.service.spec.ts

@@ -3,6 +3,22 @@ import { PageService } from './page.service';
 import { MovePageDto } from '../dto/move-page.dto';
 import { Page } from '@docmost/db/types/entity.types';
 
+// A permissive chainable Proxy stands in for the locked Kysely trx so the
+// FOR-UPDATE lock query chains inside executeTx(this.db, ...) resolve. Shared by
+// every spec that drives a transactional write (movePage cycle guard, movePage
+// provenance, movePageToSpace).
+const makeChain = () => {
+  const c: any = new Proxy(function () {}, {
+    get: (_t, p) =>
+      p === 'then'
+        ? undefined
+        : p === 'execute' || p === 'executeTakeFirst'
+          ? () => Promise.resolve([])
+          : () => c,
+  });
+  return c;
+};
+
 // Direct instantiation with stub deps. The Test.createTestingModule form failed
 // to resolve the @InjectKysely()/@InjectQueue() tokens at compile(), and this
 // smoke test only needs the service to construct.
@@ -39,12 +55,14 @@ describe('PageService', () => {
     // Build a PageService whose pageRepo (findById/updatePage) and own
     // getPageBreadCrumbs are mockable, while every other collaborator stays a
     // bare stub. We only need to drive the three cycle-guard branches, so we
-    // mock minimally rather than standing up the whole DI graph.
+    // mock minimally rather than standing up the whole DI graph. The trx stub
+    // comes from the shared module-level `makeChain` helper.
     const makeService = (overrides?: {
       breadcrumbs?: Array<{ id: string }>;
     }) => {
       const pageRepo = {
-        // Destination parent lookup: a valid, non-deleted, same-space page.
+        // Destination parent lookup: a valid, non-deleted, same-space page. Also
+        // serves the FOR-UPDATE lock reads inside the transaction.
         findById: jest.fn().mockResolvedValue({
           id: 'dest-parent',
           deletedAt: null,
@@ -57,11 +75,19 @@ describe('PageService', () => {
 
       const eventEmitter = { emit: jest.fn() };
 
+      // Re-parenting under a concrete parent now runs through
+      // executeTx(this.db, ...), which calls db.transaction().execute(fn). The
+      // trxStub is the value handed to the callback (the locked transaction).
+      const trxStub = makeChain();
+      const db = {
+        transaction: jest.fn(() => ({ execute: (fn: any) => fn(trxStub) })),
+      };
+
       const svc = new PageService(
         pageRepo as any, // pageRepo
         {} as any, // pagePermissionRepo
         {} as any, // attachmentRepo
-        {} as any, // db
+        db as any, // db
         {} as any, // storageService
         {} as any, // attachmentQueue
         {} as any, // aiQueue
@@ -79,7 +105,7 @@ describe('PageService', () => {
         .spyOn(svc, 'getPageBreadCrumbs')
         .mockResolvedValue((overrides?.breadcrumbs ?? []) as any);
 
-      return { svc, pageRepo, eventEmitter };
+      return { svc, pageRepo, eventEmitter, trxStub, db };
     };
 
     // movePage takes `movedPage` as a param. Keep its parentPageId distinct from
@@ -146,6 +172,65 @@ describe('PageService', () => {
       await expect(svc.movePage(dto, makeMovedPage())).resolves.not.toThrow();
       expect(pageRepo.updatePage).toHaveBeenCalledTimes(1);
     });
+
+    it('serializes a legitimate re-parent under FOR UPDATE in canonical lock order (#159 #9)', async () => {
+      // Destination's ancestor chain does NOT contain the moved page -> no cycle.
+      const { svc, pageRepo, trxStub } = makeService({
+        breadcrumbs: [{ id: 'dest-parent' }, { id: 'root' }],
+      });
+      const getBreadcrumbsSpy = jest.spyOn(svc, 'getPageBreadCrumbs');
+      const dto: MovePageDto = {
+        pageId: 'page-1',
+        position: VALID_POSITION,
+        parentPageId: 'dest-parent',
+      };
+
+      await expect(svc.movePage(dto, makeMovedPage())).resolves.not.toThrow();
+
+      // Both rows are locked FOR UPDATE inside the transaction: findById is
+      // called with { withLock: true, trx: <the locked tx> } for the moved page
+      // and the destination parent.
+      const lockCalls = pageRepo.findById.mock.calls.filter(
+        (c: any[]) => c[1]?.withLock === true,
+      );
+      expect(lockCalls).toHaveLength(2);
+      for (const call of lockCalls) {
+        expect(call[1].withLock).toBe(true);
+        expect(call[1].trx).toBe(trxStub);
+      }
+
+      // Locks are acquired in a canonical (id-sorted) order so the two opposing
+      // moves serialize without deadlocking.
+      const lockedIds = lockCalls.map((c: any[]) => c[0]);
+      expect(lockedIds).toEqual(['page-1', 'dest-parent'].sort());
+
+      // The cycle re-check runs inside the locked transaction (trx passed).
+      expect(getBreadcrumbsSpy).toHaveBeenCalledWith('dest-parent', trxStub);
+
+      // The update is written inside the same transaction (trx is the 3rd arg).
+      expect(pageRepo.updatePage).toHaveBeenCalledTimes(1);
+      expect(pageRepo.updatePage.mock.calls[0][2]).toBe(trxStub);
+    });
+
+    it('moves a page to root WITHOUT a transaction (no cycle possible)', async () => {
+      // A move-to-root (parentPageId === null) can never create a cycle, so it
+      // takes the unlocked else-branch: updatePage runs with NO trx and the
+      // db.transaction() serialization path is skipped entirely.
+      const { svc, pageRepo, db } = makeService();
+      const dto: MovePageDto = {
+        pageId: 'page-1',
+        position: VALID_POSITION,
+        parentPageId: null,
+      };
+
+      await expect(svc.movePage(dto, makeMovedPage())).resolves.not.toThrow();
+
+      // No FOR-UPDATE serialization: the transaction was never opened.
+      expect(db.transaction).not.toHaveBeenCalled();
+      // The update is written outside any transaction (3rd arg is undefined).
+      expect(pageRepo.updatePage).toHaveBeenCalledTimes(1);
+      expect(pageRepo.updatePage.mock.calls[0][2]).toBeUndefined();
+    });
   });
 
   describe('agent provenance stamping (#143)', () => {
@@ -259,6 +344,8 @@ describe('PageService', () => {
 
     describe('movePage() → updatePage', () => {
       const VALID_POSITION = 'a0';
+      // Re-parenting under a concrete parent runs through executeTx(this.db, ...);
+      // the shared `makeChain` helper stands in for the locked Kysely trx.
       const run = async (provenance: any) => {
         const pageRepo = {
           findById: jest.fn().mockResolvedValue({
@@ -268,9 +355,12 @@ describe('PageService', () => {
           }),
           updatePage: jest.fn().mockResolvedValue({ numUpdatedRows: 1n }),
         };
+        const trxStub = makeChain();
         const svc = makeSvc({
           pageRepo,
-          db: {} as any,
+          db: {
+            transaction: () => ({ execute: (fn: any) => fn(trxStub) }),
+          } as any,
         });
         // Legitimate move: destination ancestors do NOT include the moved page.
         jest
@@ -316,20 +406,9 @@ describe('PageService', () => {
 
     describe('movePageToSpace() → root-page updatePage', () => {
       // movePageToSpace runs its writes inside executeTx(this.db, cb), which
-      // calls this.db.transaction().execute(fn => fn(trx)). A permissive
-      // chainable Proxy stands in for the Kysely trx so arbitrary chains resolve.
-      const makeChain = () => {
-        const c: any = new Proxy(function () {}, {
-          get: (_t, p) =>
-            p === 'then'
-              ? undefined
-              : p === 'execute' || p === 'executeTakeFirst'
-                ? () => Promise.resolve([])
-                : () => c,
-        });
-        return c;
-      };
-
+      // calls this.db.transaction().execute(fn => fn(trx)). The shared
+      // `makeChain` helper stands in for the Kysely trx so arbitrary chains
+      // resolve.
       const run = async (provenance: any) => {
         const trxStub = makeChain();
         const db = {

apps/server/src/core/page/services/page.service.ts

@@ -15,13 +15,13 @@ import {
   executeWithCursorPagination,
 } from '@docmost/db/pagination/cursor-pagination';
 import { InjectKysely } from 'nestjs-kysely';
-import { KyselyDB } from '@docmost/db/types/kysely.types';
+import { KyselyDB, KyselyTransaction } from '@docmost/db/types/kysely.types';
 import { generateJitteredKeyBetween } from 'fractional-indexing-jittered';
 import { MovePageDto } from '../dto/move-page.dto';
 import { shapeSidebarPagesTree } from './sidebar-pages-tree.util';
 import { generateSlugId } from '../../../common/helpers';
 import { getPageTitle } from '../../../common/helpers';
-import { executeTx } from '@docmost/db/utils';
+import { executeTx, dbOrTx } from '@docmost/db/utils';
 import { AttachmentRepo } from '@docmost/db/repos/attachment/attachment.repo';
 import { v7 as uuid7 } from 'uuid';
 import {
@@ -915,34 +915,53 @@ export class PageService {
       }
     }
 
-    // Server-side cycle guard: a page may not be moved into itself or into any
-    // page within its own subtree. Without this, an MCP/REST/agent caller (or a
-    // fast drag racing the client check) could persist a cycle and broadcast it.
-    // Only relevant when re-parenting under a concrete parent; moving to root
-    // (parentPageId null/undefined) can never create a cycle.
-    if (dto.parentPageId) {
-      if (dto.parentPageId === dto.pageId) {
-        throw new BadRequestException('Cannot move a page into its own subtree');
-      }
-      // Walk the destination parent's ancestor chain (reusing the breadcrumb
-      // ancestor CTE). If the page being moved appears among those ancestors,
-      // the destination lives inside the moved page's subtree -> cycle.
-      const destAncestors = await this.getPageBreadCrumbs(dto.parentPageId);
-      if (destAncestors.some((ancestor) => ancestor.id === dto.pageId)) {
-        throw new BadRequestException('Cannot move a page into its own subtree');
-      }
+    // Cheap self-move guard (no DB) — keep before the transaction.
+    if (dto.parentPageId && dto.parentPageId === dto.pageId) {
+      throw new BadRequestException('Cannot move a page into its own subtree');
     }
 
-    const updateResult = await this.pageRepo.updatePage(
-      {
-        position: dto.position,
-        parentPageId: parentPageId,
-        // Agent-edit provenance: annotate the source on an agent move. A normal
-        // user request leaves the existing source value unchanged.
-        ...agentSourceFields(provenance, 'lastUpdatedSource', 'lastUpdatedAiChatId'),
-      },
-      dto.pageId,
-    );
+    const updateValues = {
+      position: dto.position,
+      parentPageId: parentPageId,
+      // Agent-edit provenance: annotate the source on an agent move. A normal
+      // user request leaves the existing source value unchanged.
+      ...agentSourceFields(provenance, 'lastUpdatedSource', 'lastUpdatedAiChatId'),
+    };
+
+    let updateResult;
+    if (typeof parentPageId === 'string') {
+      // Genuine re-parent under a concrete parent: the ONLY path that can create
+      // a cycle. Two opposing moves (A: X under Y, B: Y under X) racing each
+      // other could each pass a cycle check built from a stale snapshot and
+      // persist a cycle (#159 finding #9). Serialize them: lock the moved page
+      // and the destination parent FOR UPDATE in a canonical (id-sorted) order
+      // so they cannot deadlock, then run the cycle check INSIDE the transaction
+      // against the now-committed state.
+      updateResult = await executeTx(this.db, async (trx) => {
+        // Both opposing moves touch the same two rows {pageId, parentPageId};
+        // a fixed lock order forces one to wait for the other to commit. Lock by
+        // canonical UUIDs — `dto.pageId` can be a slugId (MovePageDto.pageId is a
+        // bare @IsString), so two opposing moves passing slugIds could sort into
+        // different lock orders and deadlock (AB-BA). `movedPage.id` is the
+        // resolved row UUID, matching `parentPageId`.
+        const lockIds = [movedPage.id, parentPageId].sort();
+        for (const id of lockIds) {
+          await this.pageRepo.findById(id, { withLock: true, trx });
+        }
+        // Re-read the destination's ancestor chain within the locked tx: it now
+        // reflects any concurrent re-parent that committed before we got the lock.
+        const destAncestors = await this.getPageBreadCrumbs(parentPageId, trx);
+        if (destAncestors.some((ancestor) => ancestor.id === dto.pageId)) {
+          throw new BadRequestException(
+            'Cannot move a page into its own subtree',
+          );
+        }
+        return this.pageRepo.updatePage(updateValues, dto.pageId, trx);
+      });
+    } else {
+      // Same-parent reorder or move-to-root: no cycle possible, no lock needed.
+      updateResult = await this.pageRepo.updatePage(updateValues, dto.pageId);
+    }
 
     // Guard against a phantom broadcast: if the row was concurrently deleted or
     // otherwise not updated, skip the PAGE_MOVED event so we don't replay a move
@@ -981,8 +1000,8 @@ export class PageService {
     });
   }
 
-  async getPageBreadCrumbs(childPageId: string) {
-    const ancestors = await this.db
+  async getPageBreadCrumbs(childPageId: string, trx?: KyselyTransaction) {
+    const ancestors = await dbOrTx(this.db, trx)
       .withRecursive('page_ancestors', (db) =>
         db
           .selectFrom('pages')

apps/server/src/database/repos/workspace/workspace.repo.ts

@@ -21,7 +21,6 @@ export const AI_PROVIDER_SETTINGS_ALLOWED: readonly string[] = [
   'driver',
   'chatModel',
   'chatApiStyle',
-  'chatContextWindow',
   'embeddingModel',
   'baseUrl',
   'embeddingBaseUrl',
@@ -256,17 +255,11 @@ export class WorkspaceRepo {
   ): Promise<Workspace> {
     const db = dbOrTx(this.db, trx);
     // Assemble the provider object IN SQL. Keys are fixed provider field names
-    // (sql.lit -> inlined literals, no injection); values are bound params with
-    // an explicit cast — postgres.js sends bound params untyped, and
-    // jsonb_build_object's value args are polymorphic ("any"), so without the
-    // cast Postgres throws "could not determine data type of parameter $1". The
-    // cast is branched by the JS runtime type so the value lands in jsonb with
-    // the matching JSON type: a number stays a JSON number (e.g.
-    // chatContextWindow → `{"chatContextWindow":200000}`, jsonb_typeof 'number'),
-    // a boolean a JSON boolean, everything else a JSON string. A plain `::text`
-    // for all would store a numeric field as the JSON STRING `"200000"`, which
-    // the client's `typeof === "number"` guards reject. The result is a real
-    // jsonb object, never a double-encoded string. The CASE self-heals
+    // (sql.lit -> inlined literals, no injection); values are bound params cast
+    // to ::text — postgres.js sends bound params untyped, and jsonb_build_object's
+    // value args are polymorphic ("any"), so without the explicit ::text cast
+    // Postgres throws "could not determine data type of parameter $1". The result
+    // is a real jsonb object, never a double-encoded string. The CASE self-heals
     // workspaces whose settings.ai.provider was previously corrupted into an
     // array/string.
     const entries = Object.entries(provider).filter(
@@ -274,14 +267,7 @@ export class WorkspaceRepo {
     );
     const patch = entries.length
       ? sql`jsonb_build_object(${sql.join(
-          entries.flatMap(([k, v]) => [
-            sql.lit(k),
-            typeof v === 'number'
-              ? sql`${v}::numeric`
-              : typeof v === 'boolean'
-                ? sql`${v}::boolean`
-                : sql`${v}::text`,
-          ]),
+          entries.flatMap(([k, v]) => [sql.lit(k), sql`${v}::text`]),
         )})`
       : sql`'{}'::jsonb`;
     return db

apps/server/src/integrations/ai/ai-provider-settings-keys.spec.ts

@@ -41,35 +41,3 @@ describe('UpdateAiSettingsDto.chatApiStyle', () => {
     expect(errs.find((e) => e.property === 'chatApiStyle')).toBeUndefined();
   });
 });
-
-/** DTO validation for chatContextWindow (@IsOptional @IsInt @Min(0)). */
-describe('UpdateAiSettingsDto.chatContextWindow', () => {
-  const errorsFor = async (chatContextWindow: unknown) =>
-    validate(plainToInstance(UpdateAiSettingsDto, { chatContextWindow }));
-
-  it('accepts a non-negative integer (incl. 0 = clear the limit)', async () => {
-    for (const v of [0, 200000]) {
-      const errs = await errorsFor(v);
-      expect(
-        errs.find((e) => e.property === 'chatContextWindow'),
-      ).toBeUndefined();
-    }
-  });
-
-  it('rejects a negative value', async () => {
-    const errs = await errorsFor(-1);
-    expect(errs.find((e) => e.property === 'chatContextWindow')).toBeDefined();
-  });
-
-  it('rejects a non-integer value', async () => {
-    const errs = await errorsFor(1.5);
-    expect(errs.find((e) => e.property === 'chatContextWindow')).toBeDefined();
-  });
-
-  it('accepts the field being omitted (optional)', async () => {
-    const errs = await validate(plainToInstance(UpdateAiSettingsDto, {}));
-    expect(
-      errs.find((e) => e.property === 'chatContextWindow'),
-    ).toBeUndefined();
-  });
-});

apps/server/src/integrations/ai/ai-settings.service.ts

@@ -27,8 +27,6 @@ export interface UpdateAiSettingsInput {
   driver?: AiDriver;
   chatModel?: string;
   chatApiStyle?: ChatApiStyle;
-  // Chat context-window size (tokens); 0/empty clears the limit.
-  chatContextWindow?: number;
   embeddingModel?: string;
   baseUrl?: string;
   embeddingBaseUrl?: string;
@@ -164,8 +162,6 @@ export class AiSettingsService {
       chatModel: provider.chatModel,
       // Plain passthrough; getChatModel defaults unset to 'openai-compatible'.
       chatApiStyle: provider.chatApiStyle,
-      // Admin-configured context-window size; 0/unset = no limit (badge denominator).
-      chatContextWindow: provider.chatContextWindow,
       // Cheap model id for the anonymous public-share assistant; reuses the chat
       // driver/baseUrl/apiKey. Empty/unset → callers fall back to chatModel.
       publicShareChatModel: provider.publicShareChatModel,
@@ -248,7 +244,6 @@ export class AiSettingsService {
       driver: provider.driver,
       chatModel: provider.chatModel,
       chatApiStyle: provider.chatApiStyle,
-      chatContextWindow: provider.chatContextWindow,
       embeddingModel: provider.embeddingModel,
       baseUrl: provider.baseUrl,
       embeddingBaseUrl: provider.embeddingBaseUrl,

apps/server/src/integrations/ai/ai.types.ts

@@ -35,13 +35,6 @@ export interface AiProviderSettings {
   // Chat provider implementation for the `openai` driver. Unset → defaults to
   // 'openai-compatible' (so reasoning is surfaced by default). See ChatApiStyle.
   chatApiStyle?: ChatApiStyle;
-  // Admin-configured chat model context-window size, in tokens. There is no
-  // provider-independent way to discover this (OpenAI's /v1/models usually omits
-  // it, Gemini/Ollama/OpenRouter each expose it differently), so it is entered
-  // manually. Surfaced to the chat client (via assistant message metadata) as the
-  // denominator of the header "current / max" context badge. Empty/0 = no limit
-  // known → the badge shows only the current context size.
-  chatContextWindow?: number;
   embeddingModel?: string;
   baseUrl?: string;
   // Embedding-specific base URL. Falls back to `baseUrl` when empty/unset.
@@ -80,7 +73,6 @@ export const PROVIDER_SETTINGS_KEYS = [
   'driver',
   'chatModel',
   'chatApiStyle',
-  'chatContextWindow',
   'embeddingModel',
   'baseUrl',
   'embeddingBaseUrl',
@@ -106,10 +98,6 @@ export const PROVIDER_SETTINGS_KEYS = [
 export interface ResolvedAiConfig extends Partial<AiProviderSettings> {
   driver?: AiDriver;
   chatModel?: string;
-  // Admin-configured chat context-window size (tokens); 0/unset = no limit. Used
-  // as the header context-badge denominator. Re-declared for parity with the
-  // explicit fields above.
-  chatContextWindow?: number;
   // Cheap model id for the public-share assistant; reuses the chat creds.
   publicShareChatModel?: string;
   // Agent-role id whose persona the public-share assistant adopts (empty/unset
@@ -129,8 +117,6 @@ export interface MaskedAiSettings {
   driver?: AiDriver;
   chatModel?: string;
   chatApiStyle?: ChatApiStyle;
-  // Admin-configured chat context-window size (tokens); 0/unset = no limit.
-  chatContextWindow?: number;
   embeddingModel?: string;
   baseUrl?: string;
   embeddingBaseUrl?: string;

apps/server/src/integrations/ai/dto/update-ai-settings.dto.ts

@@ -1,4 +1,4 @@
-import { IsIn, IsInt, IsOptional, IsString, Min } from 'class-validator';
+import { IsIn, IsOptional, IsString } from 'class-validator';
 import {
   AI_DRIVERS,
   AiDriver,
@@ -29,13 +29,6 @@ export class UpdateAiSettingsDto {
   @IsIn(CHAT_API_STYLES)
   chatApiStyle?: ChatApiStyle;
 
-  // Chat model context-window size in tokens (header context-badge denominator).
-  // 0 (or empty) clears the limit so the badge shows only the current context.
-  @IsOptional()
-  @IsInt()
-  @Min(0)
-  chatContextWindow?: number;
-
   @IsOptional()
   @IsString()
   embeddingModel?: string;

apps/server/test/integration/page-move-cycle-concurrency.int-spec.ts

@@ -0,0 +1,122 @@
+import { Kysely } from 'kysely';
+import { BadRequestException } from '@nestjs/common';
+import { PageRepo } from '@docmost/db/repos/page/page.repo';
+import { PageService } from '../../src/core/page/services/page.service';
+import {
+  getTestDb,
+  destroyTestDb,
+  createWorkspace,
+  createSpace,
+  createPage,
+} from './db';
+
+/**
+ * #159 finding #9 — concurrent opposing page moves must not create a cycle.
+ *
+ * User A drags X under Y while user B simultaneously drags Y under X. Before the
+ * fix, the cycle guard (a breadcrumb/ancestor read) and the parent-update write
+ * were NOT in a transaction, so both moves ran against a stale snapshot, both
+ * passed their cycle check, and both committed -> X.parent=Y AND Y.parent=X: a
+ * cycle with no path to root, which breaks the recursive ancestor CTEs and makes
+ * both subtrees vanish from the sidebar.
+ *
+ * The fix wraps the cycle check + update in one READ COMMITTED transaction and
+ * locks the two involved rows FOR UPDATE in a canonical (id-sorted) order, then
+ * re-runs the cycle check inside the lock. One move wins; the loser sees the
+ * committed re-parent and trips the "own subtree" guard.
+ *
+ * NOTE: this runs against real Postgres in CI (the integration suite). There is
+ * no local Postgres in dev, so it is not expected to run locally.
+ */
+describe('movePage concurrent opposing moves do not create a cycle [integration]', () => {
+  let db: Kysely<any>;
+  let workspaceId: string;
+  let spaceId: string;
+
+  beforeAll(async () => {
+    db = getTestDb();
+    workspaceId = (await createWorkspace(db)).id;
+    spaceId = (await createSpace(db, workspaceId)).id;
+  });
+
+  afterAll(async () => {
+    await destroyTestDb();
+  });
+
+  it('lets exactly one opposing move win and never persists a cycle', async () => {
+    // Real collaborators against the test DB. movePage only touches db-backed
+    // methods on pageRepo plus the db itself and the event emitter (stubbed).
+    const pageRepo = new PageRepo(
+      db as any,
+      {} as any,
+      { emit: () => undefined } as any,
+    );
+    const svc = new PageService(
+      pageRepo as any, // pageRepo
+      {} as any, // pagePermissionRepo
+      {} as any, // attachmentRepo
+      db as any, // db
+      {} as any, // storageService
+      {} as any, // attachmentQueue
+      {} as any, // aiQueue
+      {} as any, // generalQueue
+      { emit: () => undefined } as any, // eventEmitter
+      {} as any, // collaborationGateway
+      {} as any, // watcherService
+      {} as any, // transclusionService
+    );
+
+    // Seed R (root), X and Y as children of R.
+    const root = await createPage(db, { workspaceId, spaceId, title: 'R' });
+    const pageX = await createPage(db, { workspaceId, spaceId, title: 'X' });
+    const pageY = await createPage(db, { workspaceId, spaceId, title: 'Y' });
+
+    // createPage does not set parentPageId; wire X.parent=R and Y.parent=R and
+    // give each a valid fractional-index position.
+    await db
+      .updateTable('pages')
+      .set({ parentPageId: root.id, position: 'a0' })
+      .where('id', 'in', [pageX.id, pageY.id])
+      .execute();
+
+    // The Page snapshots movePage receives (parentPageId must be R so each move
+    // is a genuine re-parent rather than a same-parent reorder).
+    const movedX = await pageRepo.findById(pageX.id);
+    const movedY = await pageRepo.findById(pageY.id);
+
+    // Two opposing moves racing: A moves X under Y, B moves Y under X.
+    const results = await Promise.allSettled([
+      svc.movePage(
+        { pageId: pageX.id, parentPageId: pageY.id, position: 'a1' },
+        movedX,
+      ),
+      svc.movePage(
+        { pageId: pageY.id, parentPageId: pageX.id, position: 'a1' },
+        movedY,
+      ),
+    ]);
+
+    // Exactly one fulfilled and one rejected; the rejection is the cycle guard.
+    const fulfilled = results.filter((r) => r.status === 'fulfilled');
+    const rejected = results.filter((r) => r.status === 'rejected');
+    expect(fulfilled).toHaveLength(1);
+    expect(rejected).toHaveLength(1);
+
+    const reason = (rejected[0] as PromiseRejectedResult).reason;
+    expect(reason).toBeInstanceOf(BadRequestException);
+    expect(String(reason?.message)).toContain('own subtree');
+
+    // No cycle persisted: re-fetch X and Y and assert NOT (X->Y AND Y->X).
+    const xNow = await pageRepo.findById(pageX.id);
+    const yNow = await pageRepo.findById(pageY.id);
+    const isCycle =
+      xNow.parentPageId === pageY.id && yNow.parentPageId === pageX.id;
+    expect(isCycle).toBe(false);
+
+    // Exactly one re-parent took effect: one of X/Y still points at R, the other
+    // points at its sibling.
+    const xWon = xNow.parentPageId === pageY.id && yNow.parentPageId === root.id;
+    const yWon = yNow.parentPageId === pageX.id && xNow.parentPageId === root.id;
+    expect(xWon || yWon).toBe(true);
+  });
+});

apps/server/test/integration/workspace-repo-ai-provider-settings.int-spec.ts

@@ -1,91 +0,0 @@
-import { Kysely, sql } from 'kysely';
-import { WorkspaceRepo } from '@docmost/db/repos/workspace/workspace.repo';
-import { getTestDb, destroyTestDb, createWorkspace } from './db';
-
-/**
- * WorkspaceRepo.updateAiProviderSettings numeric round-trip (#189, #213).
- *
- * `chatContextWindow` is the first NUMERIC provider field routed through this
- * generic SQL layer. The patch builder must cast a JS number so it lands in
- * jsonb as a JSON NUMBER, not the JSON STRING `"200000"` — the client guards
- * (`typeof === "number"`) reject a string, silently killing the `/ max` badge
- * denominator. A plain `::text` cast (the prior code) regressed exactly this.
- * These specs are real SQL and assert both the JS value type and the on-disk
- * `jsonb_typeof`.
- */
-describe('WorkspaceRepo.updateAiProviderSettings (numeric round-trip) [integration]', () => {
-  let db: Kysely<any>;
-  let repo: WorkspaceRepo;
-
-  beforeAll(() => {
-    db = getTestDb();
-    repo = new WorkspaceRepo(db as any);
-  });
-
-  afterAll(async () => {
-    await destroyTestDb();
-  });
-
-  it('stores chatContextWindow as a JSON number (not a "200000" string)', async () => {
-    const ws = await createWorkspace(db, { settings: undefined });
-
-    const updated = await repo.updateAiProviderSettings(ws.id, {
-      driver: 'openai',
-      chatModel: 'gpt-4o',
-      chatContextWindow: 200000,
-    });
-
-    // Returned row: the number survives as a real JS number, alongside the
-    // string fields which stay strings.
-    const provider = (updated.settings as any)?.ai?.provider;
-    expect(provider.chatContextWindow).toBe(200000);
-    expect(typeof provider.chatContextWindow).toBe('number');
-    expect(provider.driver).toBe('openai');
-    expect(provider.chatModel).toBe('gpt-4o');
-
-    // On disk: the jsonb value is typed 'number' (the must-fix assertion), and
-    // sibling string fields are typed 'string'.
-    const typed = await db
-      .selectFrom('workspaces')
-      .select([
-        sql<string>`jsonb_typeof(settings->'ai'->'provider'->'chatContextWindow')`.as(
-          'windowType',
-        ),
-        sql<string>`jsonb_typeof(settings->'ai'->'provider'->'chatModel')`.as(
-          'modelType',
-        ),
-      ])
-      .where('id', '=', ws.id)
-      .executeTakeFirstOrThrow();
-
-    expect(typed.windowType).toBe('number');
-    expect(typed.modelType).toBe('string');
-  });
-
-  it('re-reads chatContextWindow as a number after a partial-merge update', async () => {
-    const ws = await createWorkspace(db, {
-      settings: { ai: { provider: { driver: 'openai', chatModel: 'x' } } },
-    });
-
-    // Merge in only the numeric field; siblings must be preserved and the value
-    // must still be a JSON number, not a string.
-    await repo.updateAiProviderSettings(ws.id, { chatContextWindow: 128000 });
-
-    const row = await db
-      .selectFrom('workspaces')
-      .select([
-        'settings',
-        sql<string>`jsonb_typeof(settings->'ai'->'provider'->'chatContextWindow')`.as(
-          'windowType',
-        ),
-      ])
-      .where('id', '=', ws.id)
-      .executeTakeFirstOrThrow();
-
-    expect(row.windowType).toBe('number');
-    const provider = (row.settings as any)?.ai?.provider;
-    expect(provider.chatContextWindow).toBe(128000);
-    expect(provider.driver).toBe('openai');
-    expect(provider.chatModel).toBe('x');
-  });
-});