docs: add how-to-test.md (browser E2E + out-of-band) and link from AGENTS.md

Adds a testing guide covering how to verify features against a running stand:
drive the behaviour under test through the browser (not the API), verify
out-of-band in the DB/git, and the non-obvious traps. Notably the page has two
ProseMirror editors — [aria-label='Page title'] (non-collab) and
[aria-label='Page content'] (the collab body); querySelector('.ProseMirror')
returns the title, so tests must target the body editor and wait ~10s for the
hocuspocus store debounce. Links the new doc from AGENTS.md next to dev-stand.md
and adds a matching gotcha #8 to dev-stand.md.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.github/workflows/test.yml

@@ -13,6 +13,49 @@ permissions:
   contents: read
 
 jobs:
+  # Guard against a long-lived branch adding a migration whose timestamped
+  # filename sorts BEFORE migrations already applied on the target branch (and
+  # thus in prod). The Kysely startup migrator rejects that as "corrupted
+  # migrations" and crash-loops the app on boot (incident #361). This gate fails
+  # the PR so the migration is renamed to a current timestamp before merge. Only
+  # runs for pull_request events (needs a base branch to diff against).
+  migration-order:
+    if: github.event_name == 'pull_request'
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    steps:
+      - name: Checkout (full history for the base-branch diff)
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Added migrations must sort after the newest on the base branch
+        env:
+          TARGET_BRANCH: ${{ github.base_ref }}
+        run: |
+          set -euo pipefail
+          MIG_DIR="apps/server/src/database/migrations"
+          # checkout above already did fetch-depth:0 (full history). Fetch the base
+          # WITHOUT --depth (a shallow graft would truncate the base history and
+          # break the merge-base when the base has moved ahead of the PR merge —
+          # exactly the long-branch-vs-moving-base case this gate guards, #361).
+          git fetch --no-tags origin "$TARGET_BRANCH"
+          newest_on_target=$(git ls-tree -r --name-only "origin/${TARGET_BRANCH}" "$MIG_DIR" | sort | tail -1)
+          # NO `|| true`: a diff failure (e.g. an unresolved merge-base) must fail
+          # the job CLOSED — a gate whose job is to BLOCK must never pass on error.
+          # `set -e` above already aborts on a non-zero diff exit.
+          added=$(git diff --diff-filter=A --name-only "origin/${TARGET_BRANCH}...HEAD" -- "$MIG_DIR")
+          bad=0
+          for f in $added; do
+            if [[ "$f" < "$newest_on_target" || "$f" == "$newest_on_target" ]]; then
+              echo "::error::Migration $f sorts at or before the newest on ${TARGET_BRANCH} ($newest_on_target) — rename it with a CURRENT timestamp before merge (do not change its contents). See incident #361."
+              bad=1
+            fi
+          done
+          if [ "$bad" -eq 0 ]; then
+            echo "Migration order OK (added migrations all sort after $newest_on_target)."
+          fi
+          exit $bad
+
   test:
     runs-on: ubuntu-latest
     timeout-minutes: 20

AGENTS.md

@@ -201,7 +201,7 @@ pnpm workspace (`pnpm@10.4.0`) orchestrated by **Nx**. Four workspace packages:
 | `apps/client` | `client` | React 18 + Vite + Mantine 8 + TanStack Query + Jotai | SPA frontend |
 | `packages/editor-ext` | `@docmost/editor-ext` | Tiptap/ProseMirror | Shared Tiptap node/mark extensions, imported by both the client and the server |
 | `packages/mcp` | `@docmost/mcp` | MCP SDK, Tiptap, Yjs | Standalone MCP server, also bundled into the server at `/mcp`. Consumes the shared converter/schema from `@docmost/prosemirror-markdown` (#293) — it no longer carries its own vendored converter/schema copy |
-| `packages/prosemirror-markdown` | `@docmost/prosemirror-markdown` | Tiptap, marked, jsdom | The single, canonical ProseMirror↔Markdown converter + Docmost schema mirror (#293). Consumed by `mcp` and `git-sync`; there is exactly ONE copy of the converter now |
+| `packages/prosemirror-markdown` | `@docmost/prosemirror-markdown` | Tiptap, marked, jsdom | The single, canonical ProseMirror↔Markdown converter + Docmost schema mirror (#293). Consumed by `mcp`, `git-sync`, AND `apps/server` (server-side markdown import/export, #345); there is exactly ONE copy of the converter now |
 
 `build` targets are Nx-cached and dependency-ordered (`dependsOn: ["^build"]`), so `editor-ext` builds before the apps. `nx.json` sets `affected.defaultBase: main`.
 
@@ -214,6 +214,12 @@ Run from the repo root unless noted. The dev workflow needs **Postgres (with the
 > server, `APP_SECRET` mismatch between processes, a stale `editor-ext` white-
 > screening the client, LAN exposure. See **[docs/dev-stand.md](docs/dev-stand.md)**
 > for the step-by-step and the traps.
+>
+> **Testing the app against a stand** (browser E2E + out-of-band verification) has
+> its own non-obvious traps — the page has two ProseMirror editors (only the body is
+> collab-bound), a ~10s store debounce, and API-seeding the thing under test is a
+> silent no-test. See **[docs/how-to-test.md](docs/how-to-test.md)** before writing
+> UI tests.
 
 ```bash
 pnpm install                 # install all workspaces (uses pnpm patches; see package.json `pnpm.patchedDependencies`)
@@ -250,7 +256,10 @@ pnpm --filter server migration:codegen                   # regenerate src/databa
 ```
 Migration files live in `apps/server/src/database/migrations/` and are named `YYYYMMDDThhmmss-description.ts`. Fork-specific migrations only **add** tables (`page_embeddings`, `ai_chats`, `ai_chat_messages`, `ai_provider_credentials`, `ai_mcp_servers`, `page_template_references`) and columns (e.g. `pages.is_template`, a `NOT NULL DEFAULT false` boolean) — never drop/rewrite Docmost data.
 
-**Migration ordering — always check when merging branches/features.** Kysely runs migrations in **alphabetical (= timestamp) order** and refuses to start if a *new* migration sorts **before** one already applied to the DB (`corrupted migrations: ... must always have a name that comes alphabetically after the last executed migration`). When you merge a branch or land a feature, verify your migration's timestamp still sorts **after every migration that may already be applied on the target** (`/bin/ls -1 apps/server/src/database/migrations | sort | tail`). Branches developed in parallel routinely break this: a feature branch adds `…T130000-…`, `main` meanwhile ships and deploys `…T150000-…`, and after the merge the older-timestamped file is rejected at boot. **Fix = rename your migration to a timestamp after the latest one already in the target** (content unchanged — the filename is the ordering key), then rebuild so the compiled `dist/database/migrations/` picks up the new name.
+**Migration ordering — always check when merging branches/features.** Kysely runs migrations in **alphabetical (= timestamp) order**. A *new* migration that sorts **before** one already applied to the DB is a "back-dated" migration, which branches developed in parallel routinely produce: a feature branch adds `…T130000-…`, `develop` meanwhile ships and deploys `…T150000-…`, and after the merge the older-timestamped file has been skipped. Two layers guard this (both added for incident #361, where a back-dated migration crash-looped prod for ~11 min):
+
+- **CI gate (primary):** the `migration-order` job in `.github/workflows/test.yml` fails a PR whose added migration sorts at/before the newest on the base branch. **So the fix is to rename your migration to a timestamp after the latest one already in the target** (`/bin/ls -1 apps/server/src/database/migrations | sort | tail`; content unchanged — the filename is the ordering key), then rebuild so the compiled `dist/database/migrations/` picks up the new name.
+- **Runtime safety net:** both Migrators (`migration.service.ts` startup auto-migrate + `migrate.ts` CLI) set `allowUnorderedMigrations: true`, so the app does **not** refuse to start on an out-of-order migration — it applies the skipped older one instead of crash-looping. Kysely's `#ensureNoMissingMigrations` guard is still on (a *removed* applied migration is still an error). Because apply order can then differ from lexicographic across instances, migrations must stay **independent** (each creates its own objects) — the CI gate remains the primary line; this net only covers a gate bypass (manual push / hotfix branch).
 
 ## Architecture — the big picture
 
@@ -284,7 +293,7 @@ The API server is a Fastify app with a global `/api` prefix (`main.ts` excludes
 ### Client structure
 Vite SPA. Code is organized by feature under `apps/client/src/features/*` (mirrors the server domains: `page`, `space`, `comment`, `ai-chat`, `editor`, …). Conventions:
 - **TanStack Query** for server state (one `queries/` file per feature), **Jotai** atoms for local/shared UI state, **Mantine 8** + CSS modules (`*.module.css`) + `postcss-preset-mantine` for UI.
-- The editor is Tiptap; shared node/mark extensions live in `packages/editor-ext` and are imported by **both the client and the server** (collaboration, import/export) — editor schema changes often need to be made in `editor-ext`, not just the client. The ProseMirror↔Markdown converter and its Docmost schema mirror now live in a SINGLE package, `@docmost/prosemirror-markdown` (#293), consumed by both `mcp` and `git-sync` — do NOT reintroduce a per-package copy. `editor-ext` is the upstream source of the Tiptap schema; the package's `docmost-schema.ts` mirrors it and a serializer-contract test (`packages/prosemirror-markdown/test/serializer-contract.test.ts`) guards the boundary (every schema node must have a converter case), so a drift surfaces as a failing test rather than silent divergence.
+- The editor is Tiptap; shared node/mark extensions live in `packages/editor-ext` and are imported by **both the client and the server** (collaboration, schema, `canonicalizeFootnotes`) — editor schema changes often need to be made in `editor-ext`, not just the client. Server-side markdown import/export no longer lives in `editor-ext`: it goes through the canonical converter (#345, see below). The ProseMirror↔Markdown converter and its Docmost schema mirror now live in a SINGLE package, `@docmost/prosemirror-markdown` (#293), consumed by `mcp`, `git-sync`, and `apps/server` (#345) — do NOT reintroduce a per-package copy. `editor-ext` is the upstream source of the Tiptap schema; the package's `docmost-schema.ts` mirrors it and a serializer-contract test (`packages/prosemirror-markdown/test/serializer-contract.test.ts`) guards the boundary (every schema node must have a converter case), so a drift surfaces as a failing test rather than silent divergence.
 - API access goes through `apps/client/src/lib/api-client.ts` (axios). The `@` alias maps to `apps/client/src`.
 - Runtime config is injected at build time by `vite.config.ts` via `define` (`APP_URL`, `COLLAB_URL`, `APP_VERSION`, …) — these come from the root `.env`, not from `import.meta.env`.
 
@@ -294,7 +303,7 @@ Vite SPA. Code is organized by feature under `apps/client/src/features/*` (mirro
 - **Errors must never be swallowed or shown as generic messages.** Every caught error MUST (1) be logged in full to the console/logger — error name, message, stack, `cause`, and (for HTTP/provider failures) the status code and response body — and (2) be surfaced to the user with a *specific, human-readable explanation of what actually went wrong*, never a bare generic string like "Something went wrong" / "Could not start recording" / "Transcription failed". Include the real reason (the underlying error/provider message) in the user-facing text. On the server, wrap third-party/provider failures with `describeProviderError` (or equivalent) and rethrow as a meaningful HTTP status + message — never let them collapse into an opaque 500. On the client, `console.error(<context>, err)` the raw error AND show the extracted reason (e.g. `err.response?.data?.message`, or the error `name: message`) in the notification.
 - The version string shown in the UI comes from `APP_VERSION` (CI/Docker) or `git describe --tags --always` (local), resolved in `vite.config.ts` — not from `package.json`.
 - Server TS config is permissive (`noImplicitAny: false`, `strictNullChecks: false`, `no-explicit-any` lint disabled). Follow the existing relaxed style rather than tightening types broadly.
-- Dependency versions are heavily pinned via `pnpm.overrides` and `pnpm.patchedDependencies` (`scimmy`, `yjs`) in the root `package.json`. Don't bump pinned/patched deps casually; the patches and overrides exist for compatibility/security reasons.
+- Dependency versions are heavily pinned via `pnpm.overrides` and `pnpm.patchedDependencies` (`scimmy`, `yjs`, `ai`) in the root `package.json`. Don't bump pinned/patched deps casually; the patches and overrides exist for compatibility/security reasons. The `ai@6.0.134` patch disables the SDK's O(n²) cumulative `partialOutput` accumulation when no output strategy is requested (server heap OOM on long agent runs, #184; tripwire test: `apps/server/src/integrations/ai/ai-sdk-partial-output.patch.spec.ts`) — it MUST be re-created via `pnpm patch` when bumping `ai`.
 - **Adding/renaming/removing an MCP tool requires updating `SERVER_INSTRUCTIONS`** in `packages/mcp/src/index.ts` — the intent-routing guide MCP clients receive on initialize. This applies both to inline `server.registerTool(...)` calls in `index.ts` and to specs in `packages/mcp/src/tool-specs.ts`. Enforced by `packages/mcp/test/unit/server-instructions.test.mjs`, which fails when a registered tool is not mentioned in the guide (deliberate opt-outs go into its `EXCEPTIONS` list). `packages/mcp/build/` is gitignored and rebuilt in CI/Docker via `pnpm build` (same convention as `git-sync`/`prosemirror-markdown`) — never commit it; rebuild locally after editing to run the tests.
 
 ## CI / release

CHANGELOG.md

@@ -169,6 +169,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- **The server no longer runs out of heap during long autonomous agent runs.** A
+  new pnpm patch on `ai@6.0.134` stops the SDK from building a cumulative
+  snapshot of the ENTIRE turn text on every streamed text-delta when no output
+  strategy was requested (our server never requests one). Unpatched, those
+  O(n²) `partialOutput` snapshots piled up in a never-consumed internal
+  `tee()` branch of the stream result — a ~20-step, ~28k-chunk agent run
+  retained ~1.7 GB and OOM'd the 2 GB JS heap. Streaming granularity is
+  unchanged; the patch must be re-created if `ai` is ever bumped. (#184)
 - **Internal links in exported Markdown no longer lose their visible text.** A
   link whose target page name had no file extension (e.g. a bare title) was
   collapsed to empty text during export, producing an unclickable, label-less

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

@@ -1373,6 +1373,39 @@
   "The role catalog is unavailable": "The role catalog is unavailable",
   "Please try again later.": "Please try again later.",
   "No bundles available": "No bundles available",
+  "Content": "Content",
+  "Content language of the roles": "Content language of the roles",
+  "{{count}} updates available in {{bundles}} bundles": "{{count}} updates available in {{bundles}} bundles",
+  "Update all ({{count}})": "Update all ({{count}})",
+  "Updating {{current}}/{{total}}…": "Updating {{current}}/{{total}}…",
+  "{{count}} roles are installed in another language. A different language installs separately and appears as new.": "{{count}} roles are installed in another language. A different language installs separately and appears as new.",
+  "{{count}} roles": "{{count}} roles",
+  "{{count}} new — none installed": "{{count}} new — none installed",
+  "All installed · up to date": "All installed · up to date",
+  "{{count}} updates · {{installed}} up to date": "{{count}} updates · {{installed}} up to date",
+  "{{count}} new": "{{count}} new",
+  "{{count}} installed": "{{count}} installed",
+  "{{count}} updates": "{{count}} updates",
+  "Install bundle": "Install bundle",
+  "Install {{count}} selected": "Install {{count}} selected",
+  "Install bundle ({{count}})": "Install bundle ({{count}})",
+  "{{selected}} of {{total}} selected": "{{selected}} of {{total}} selected",
+  "Select all": "Select all",
+  "Deselect all": "Deselect all",
+  "Skipped": "Skipped",
+  "v{{version}}": "v{{version}}",
+  "{{count}} roles installed": "{{count}} roles installed",
+  "{{count}} roles installed · {{renamed}} renamed": "{{count}} roles installed · {{renamed}} renamed",
+  "{{count}} roles updated": "{{count}} roles updated",
+  "Installed {{installed}} · {{skipped}} skipped": "Installed {{installed}} · {{skipped}} skipped",
+  "A role named \"{{name}}\" already exists in this workspace.": "A role named \"{{name}}\" already exists in this workspace.",
+  "\"{{name}}\" is already installed.": "\"{{name}}\" is already installed.",
+  "Rename & install": "Rename & install",
+  "Couldn’t load the catalog": "Couldn’t load the catalog",
+  "Check your connection and try again. Installed roles are not affected.": "Check your connection and try again. Installed roles are not affected.",
+  "Retry": "Retry",
+  "The catalog is empty": "The catalog is empty",
+  "No role bundles are published for this language yet. Try switching the content language.": "No role bundles are published for this language yet. Try switching the content language.",
   "Already up to date": "Already up to date",
   "Updated to the latest version": "Updated to the latest version",
   "This role is no longer in the catalog": "This role is no longer in the catalog",

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

@@ -1235,6 +1235,39 @@
   "The role catalog is unavailable": "Каталог ролей недоступен",
   "Please try again later.": "Попробуйте позже.",
   "No bundles available": "Наборы недоступны",
+  "Content": "Язык контента",
+  "Content language of the roles": "Язык контента ролей",
+  "{{count}} updates available in {{bundles}} bundles": "Доступно обновлений: {{count}} в наборах: {{bundles}}",
+  "Update all ({{count}})": "Обновить все ({{count}})",
+  "Updating {{current}}/{{total}}…": "Обновление {{current}}/{{total}}…",
+  "{{count}} roles are installed in another language. A different language installs separately and appears as new.": "Ролей установлено на другом языке: {{count}}. Другой язык устанавливается отдельно и отображается как новый.",
+  "{{count}} roles": "ролей: {{count}}",
+  "{{count}} new — none installed": "новых: {{count}} — ничего не установлено",
+  "All installed · up to date": "Все установлены · актуальны",
+  "{{count}} updates · {{installed}} up to date": "обновлений: {{count}} · актуальны: {{installed}}",
+  "{{count}} new": "новых: {{count}}",
+  "{{count}} installed": "установлено: {{count}}",
+  "{{count}} updates": "обновлений: {{count}}",
+  "Install bundle": "Установить набор",
+  "Install {{count}} selected": "Установить выбранные ({{count}})",
+  "Install bundle ({{count}})": "Установить набор ({{count}})",
+  "{{selected}} of {{total}} selected": "выбрано {{selected}} из {{total}}",
+  "Select all": "Выбрать все",
+  "Deselect all": "Снять выбор",
+  "Skipped": "Пропущено",
+  "v{{version}}": "v{{version}}",
+  "{{count}} roles installed": "Установлено ролей: {{count}}",
+  "{{count}} roles installed · {{renamed}} renamed": "Установлено ролей: {{count}} · переименовано: {{renamed}}",
+  "{{count}} roles updated": "Обновлено ролей: {{count}}",
+  "Installed {{installed}} · {{skipped}} skipped": "Установлено: {{installed}} · пропущено: {{skipped}}",
+  "A role named \"{{name}}\" already exists in this workspace.": "Роль с именем «{{name}}» уже существует в этом рабочем пространстве.",
+  "\"{{name}}\" is already installed.": "«{{name}}» уже установлена.",
+  "Rename & install": "Переименовать и установить",
+  "Couldn’t load the catalog": "Не удалось загрузить каталог",
+  "Check your connection and try again. Installed roles are not affected.": "Проверьте подключение и попробуйте снова. Установленные роли не затронуты.",
+  "Retry": "Повторить",
+  "The catalog is empty": "Каталог пуст",
+  "No role bundles are published for this language yet. Try switching the content language.": "Для этого языка ещё не опубликовано ни одного набора ролей. Попробуйте сменить язык контента.",
   "No roles configured": "Роли не настроены",
   "Already up to date": "Уже актуальна",
   "Updated to the latest version": "Обновлено до последней версии",

apps/client/src/features/ai-chat/queries/ai-chat-query.ts

@@ -1,6 +1,7 @@
 import {
   useInfiniteQuery,
   useMutation,
+  useQueries,
   useQuery,
   useQueryClient,
 } from "@tanstack/react-query";
@@ -307,6 +308,29 @@ export function useAiRoleCatalogBundleQuery(
   });
 }
 
+/**
+ * Eagerly open EVERY listed bundle's content in parallel for one language. The
+ * redesigned catalog shows each bundle's status summary in its COLLAPSED header,
+ * which needs every role's install state up front — so contents can no longer be
+ * lazy-loaded on expand. The catalog is small, so a fan-out of `useQueries` (one
+ * cached read per bundle, sharing the same cache keys as
+ * `useAiRoleCatalogBundleQuery`) is cheap. Gated by `enabled` (modal open + a
+ * resolved language) so nothing fetches while the modal is closed.
+ */
+export function useAiRoleCatalogBundlesQueries(
+  bundleIds: string[],
+  language: string,
+  enabled: boolean,
+) {
+  return useQueries({
+    queries: bundleIds.map((bundleId) => ({
+      queryKey: AI_ROLE_CATALOG_BUNDLE_RQ_KEY(bundleId, language),
+      queryFn: () => getAiRoleCatalogBundle(bundleId, language),
+      enabled: enabled && !!language,
+    })),
+  });
+}
+
 export function useImportAiRolesFromCatalogMutation() {
   const queryClient = useQueryClient();
   const { t } = useTranslation();

apps/client/src/features/ai-chat/queries/import-from-catalog-message.test.tsx

@@ -77,7 +77,14 @@ describe("useImportAiRolesFromCatalogMutation — success notifications", () =>
   });
 
   it("errors:[] -> only the summary notification (counts interpolated)", async () => {
-    await runMutation({ created: 3, renamed: 1, skipped: 2, errors: [] });
+    await runMutation({
+      created: 3,
+      renamed: 1,
+      skipped: 2,
+      errors: [],
+      createdRoles: [],
+      skippedRoles: [],
+    });
     expect(notificationsShowMock).toHaveBeenCalledTimes(1);
     expect(notificationsShowMock).toHaveBeenCalledWith({
       message: "Imported 3, renamed 1, skipped 2",
@@ -93,6 +100,8 @@ describe("useImportAiRolesFromCatalogMutation — success notifications", () =>
         { slug: "a", message: "name taken" },
         { slug: "b", message: "name taken" },
       ],
+      createdRoles: [{ slug: "ok", name: "Ok" }],
+      skippedRoles: [],
     });
     expect(notificationsShowMock).toHaveBeenCalledTimes(2);
     expect(notificationsShowMock).toHaveBeenNthCalledWith(1, {

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

@@ -108,12 +108,25 @@ export interface IAiRoleImportPayload {
   conflict: "skip" | "rename";
 }
 
-/** Import result counts (mirrors `importFromCatalog()`). */
+/**
+ * Import result (mirrors `importFromCatalog()`). The counters (`created`,
+ * `skipped`, `renamed`) drive the summary notification; the per-role lists
+ * (`createdRoles`, `skippedRoles`) drive the redesigned catalog modal's inline
+ * result plaque — which roles were installed (and any rename) and which were
+ * skipped and why (so the plaque can name the conflicting role and offer
+ * "Rename & install").
+ */
 export interface IAiRoleImportResult {
   created: number;
   skipped: number;
   renamed: number;
   errors: { slug: string; message: string }[];
+  createdRoles: { slug: string; name: string; renamedTo?: string }[];
+  skippedRoles: {
+    slug: string;
+    name: string;
+    reason: "name-conflict" | "already-installed";
+  }[];
 }
 
 /**

apps/client/src/features/ai-chat/utils/catalog-bundle-model.test.ts

@@ -0,0 +1,234 @@
+import { describe, it, expect } from "vitest";
+import {
+  bundleCounts,
+  bundlePhase,
+  installedLangForRole,
+  mapBundleRolesToView,
+  mapCatalogRoleToView,
+  nameConflictSlugs,
+  partialOffersRename,
+  type CatalogViewRole,
+} from "./catalog-bundle-model.ts";
+import type {
+  IAiRole,
+  IAiRoleCatalogRole,
+} from "@/features/ai-chat/types/ai-chat.types.ts";
+
+function installedRole(
+  source: { slug: string; language: string; version: number },
+  overrides: Partial<IAiRole> = {},
+): IAiRole {
+  return {
+    id: `role-${source.slug}-${source.language}`,
+    name: source.slug,
+    emoji: null,
+    description: null,
+    enabled: true,
+    autoStart: true,
+    launchMessage: null,
+    source,
+    ...overrides,
+  };
+}
+
+function catalogRole(
+  overrides: Partial<IAiRoleCatalogRole> = {},
+): IAiRoleCatalogRole {
+  return {
+    slug: "writer",
+    emoji: "✍️",
+    name: "Writer",
+    description: "Drafts copy.",
+    instructions: "be a writer",
+    autoStart: true,
+    launchMessage: null,
+    version: 3,
+    ...overrides,
+  };
+}
+
+// Build a minimal view role for bundlePhase tests.
+function viewRole(status: CatalogViewRole["status"]): CatalogViewRole {
+  return { slug: `s-${status}`, name: status, description: "", version: 1, status };
+}
+
+describe("bundlePhase", () => {
+  it("empty bundle -> empty", () => {
+    expect(bundlePhase([])).toBe("empty");
+  });
+
+  it("all importable, none installed -> allNew", () => {
+    expect(bundlePhase([viewRole("import"), viewRole("import")])).toBe(
+      "allNew",
+    );
+  });
+
+  it("nothing to import or update -> allInstalled", () => {
+    expect(bundlePhase([viewRole("installed"), viewRole("installed")])).toBe(
+      "allInstalled",
+    );
+  });
+
+  it("updates present, nothing to import -> updates", () => {
+    expect(bundlePhase([viewRole("update"), viewRole("installed")])).toBe(
+      "updates",
+    );
+  });
+
+  it("import + installed (no updates) -> mixed", () => {
+    expect(bundlePhase([viewRole("import"), viewRole("installed")])).toBe(
+      "mixed",
+    );
+  });
+
+  it("import + update -> mixed", () => {
+    expect(bundlePhase([viewRole("import"), viewRole("update")])).toBe("mixed");
+  });
+
+  it("a skipped role with nothing installed -> mixed (NOT allInstalled)", () => {
+    // F1: a bundle whose only non-installed role was skipped has 0 installed for
+    // it, so the collapsed 'All installed · up to date' header would contradict
+    // the open 'Installed 0 · 1 skipped' plaque. It must be mixed until resolved.
+    expect(bundlePhase([viewRole("skipped")])).toBe("mixed");
+  });
+
+  it("installed + a skipped role -> mixed (partial success is not allInstalled)", () => {
+    expect(bundlePhase([viewRole("installed"), viewRole("skipped")])).toBe(
+      "mixed",
+    );
+  });
+});
+
+describe("bundleCounts", () => {
+  it("tallies each status once", () => {
+    expect(
+      bundleCounts([
+        viewRole("import"),
+        viewRole("import"),
+        viewRole("installed"),
+        viewRole("update"),
+        viewRole("skipped"),
+      ]),
+    ).toEqual({ importable: 2, installed: 1, update: 1, skipped: 1 });
+  });
+});
+
+describe("nameConflictSlugs / partialOffersRename (reason -> action)", () => {
+  it("only name-conflict skips become the transient overlay / offer rename", () => {
+    const skipped = [
+      { slug: "writer", name: "Writer", reason: "name-conflict" as const },
+      { slug: "editor", name: "Editor", reason: "already-installed" as const },
+    ];
+    expect(nameConflictSlugs(skipped)).toEqual(["writer"]);
+    expect(partialOffersRename(skipped)).toBe(true);
+  });
+
+  it("an already-installed-only skip is informational: no overlay, no rename", () => {
+    const skipped = [
+      { slug: "editor", name: "Editor", reason: "already-installed" as const },
+    ];
+    expect(nameConflictSlugs(skipped)).toEqual([]);
+    expect(partialOffersRename(skipped)).toBe(false);
+  });
+});
+
+describe("installedLangForRole", () => {
+  it("returns the other language when the same slug is installed elsewhere", () => {
+    const roles = [installedRole({ slug: "writer", language: "ru", version: 2 })];
+    expect(installedLangForRole("writer", roles, "en")).toBe("ru");
+  });
+
+  it("returns undefined when the same slug is installed in the SAME language", () => {
+    const roles = [installedRole({ slug: "writer", language: "en", version: 2 })];
+    expect(installedLangForRole("writer", roles, "en")).toBeUndefined();
+  });
+
+  it("returns undefined when no install of the slug exists", () => {
+    expect(installedLangForRole("writer", [], "en")).toBeUndefined();
+  });
+
+  it("ignores manually-created roles (no source)", () => {
+    const roles = [
+      installedRole({ slug: "writer", language: "ru", version: 2 }, {
+        source: null,
+      }),
+    ];
+    expect(installedLangForRole("writer", roles, "en")).toBeUndefined();
+  });
+});
+
+describe("mapCatalogRoleToView", () => {
+  it("no install -> import status, catalog version, emoji preserved", () => {
+    const view = mapCatalogRoleToView(catalogRole(), [], "en");
+    expect(view).toMatchObject({
+      slug: "writer",
+      emoji: "✍️",
+      name: "Writer",
+      description: "Drafts copy.",
+      status: "import",
+      version: 3,
+    });
+    expect(view.installedRoleId).toBeUndefined();
+    expect(view.installedLang).toBeUndefined();
+  });
+
+  it("import with the slug installed in another language -> installedLang set", () => {
+    const roles = [installedRole({ slug: "writer", language: "ru", version: 9 })];
+    const view = mapCatalogRoleToView(catalogRole(), roles, "en");
+    expect(view.status).toBe("import");
+    expect(view.installedLang).toBe("ru");
+  });
+
+  it("installed (up to date) -> installed status, catalog version, installedRoleId", () => {
+    const installed = installedRole({
+      slug: "writer",
+      language: "en",
+      version: 3,
+    });
+    const view = mapCatalogRoleToView(catalogRole(), [installed], "en");
+    expect(view).toMatchObject({
+      status: "installed",
+      version: 3,
+      installedRoleId: installed.id,
+    });
+  });
+
+  it("update -> version=from, newVersion=to, installedRoleId", () => {
+    const installed = installedRole({
+      slug: "writer",
+      language: "en",
+      version: 1,
+    });
+    const view = mapCatalogRoleToView(catalogRole(), [installed], "en");
+    expect(view).toMatchObject({
+      status: "update",
+      version: 1,
+      newVersion: 3,
+      installedRoleId: installed.id,
+    });
+  });
+
+  it("missing emoji -> emoji undefined; null description -> empty string", () => {
+    const view = mapCatalogRoleToView(
+      catalogRole({ emoji: null, description: null }),
+      [],
+      "en",
+    );
+    expect(view.emoji).toBeUndefined();
+    expect(view.description).toBe("");
+  });
+});
+
+describe("mapBundleRolesToView", () => {
+  it("maps a bundle's roles preserving order", () => {
+    const roles = [
+      catalogRole({ slug: "a", name: "A", version: 1 }),
+      catalogRole({ slug: "b", name: "B", version: 1 }),
+    ];
+    const installed = [installedRole({ slug: "a", language: "en", version: 1 })];
+    const view = mapBundleRolesToView(roles, installed, "en");
+    expect(view.map((r) => r.slug)).toEqual(["a", "b"]);
+    expect(view[0].status).toBe("installed");
+    expect(view[1].status).toBe("import");
+  });
+});

apps/client/src/features/ai-chat/utils/catalog-bundle-model.ts

@@ -0,0 +1,206 @@
+import type {
+  IAiRole,
+  IAiRoleCatalogRole,
+} from "@/features/ai-chat/types/ai-chat.types.ts";
+import { catalogRoleInstallState } from "@/features/ai-chat/utils/catalog-role-install-state.ts";
+
+/**
+ * The redesigned catalog modal renders bundles as cards with a summary status
+ * (readable without expanding) and a single primary action. The per-role and
+ * per-bundle view model that drives that UI is derived here as PURE functions so
+ * the mapping, the "installed in another language" hint, and the bundle-phase
+ * computation are unit-testable without mounting the component (mirrors the
+ * `catalogRoleInstallState` precedent).
+ */
+
+/**
+ * A role's status in the catalog view model.
+ *  - `import`    — not installed in the current content language.
+ *  - `installed` — installed and up to date.
+ *  - `update`    — installed, but the catalog ships a newer version.
+ *  - `skipped`   — TRANSIENT client-only status set after a conflicted import
+ *                  (a name collision under `conflict:'skip'`); never from the
+ *                  backend.
+ */
+export type RoleStatus = "import" | "installed" | "update" | "skipped";
+
+/** A catalog role mapped into the modal's view model. */
+export interface CatalogViewRole {
+  // Slug is the stable identity within a bundle; used as the row key and as the
+  // `slugs[]` payload for import.
+  slug: string;
+  // Optional in the catalog — the row reserves space and renders nothing when
+  // absent.
+  emoji?: string;
+  name: string;
+  description: string;
+  // For `installed`/`import`: the catalog version. For `update`: the installed
+  // (from) version, with `newVersion` holding the catalog (to) version.
+  version: number;
+  newVersion?: number;
+  status: RoleStatus;
+  // The language a same-slug role is installed under, when it differs from the
+  // current content language (drives the Р5 hint). Only set for `import` roles.
+  installedLang?: string;
+  // The workspace role id, present for `installed`/`update` — needed to call the
+  // update-from-catalog mutation.
+  installedRoleId?: string;
+}
+
+/**
+ * The summary phase of a bundle, derived from its roles' statuses. Determines
+ * the collapsed-header summary and the bundle's single primary action.
+ *  - `empty`        — the bundle has no roles.
+ *  - `allNew`       — everything is importable, nothing installed.
+ *  - `allInstalled` — everything installed & up to date; nothing else pending.
+ *  - `updates`      — updates available and nothing left to import.
+ *  - `mixed`        — any other combination.
+ */
+export type BundlePhase =
+  | "empty"
+  | "allNew"
+  | "allInstalled"
+  | "updates"
+  | "mixed";
+
+/** Per-status tallies for a bundle's roles (the single source of truth). */
+export interface BundleCounts {
+  importable: number;
+  installed: number;
+  update: number;
+  skipped: number;
+}
+
+/**
+ * Count a bundle's roles by status ONCE. Both `bundlePhase` and the panel derive
+ * from this, so the tally logic lives in exactly one place (no rescans / drift).
+ */
+export function bundleCounts(roles: CatalogViewRole[]): BundleCounts {
+  const counts: BundleCounts = {
+    importable: 0,
+    installed: 0,
+    update: 0,
+    skipped: 0,
+  };
+  for (const r of roles) {
+    if (r.status === "import") counts.importable += 1;
+    else if (r.status === "installed") counts.installed += 1;
+    else if (r.status === "update") counts.update += 1;
+    else if (r.status === "skipped") counts.skipped += 1;
+  }
+  return counts;
+}
+
+export function bundlePhase(roles: CatalogViewRole[]): BundlePhase {
+  if (roles.length === 0) return "empty";
+  const { importable, installed, update, skipped } = bundleCounts(roles);
+  // A `skipped` role is a pending post-import conflict (0 installed for it), so a
+  // bundle that has ANY skipped role is NOT "all installed & up to date" — that
+  // would make the collapsed green "up to date" header contradict the open
+  // panel's "Installed 0 · 1 skipped" plaque. It is `mixed` until resolved.
+  if (importable === 0 && update === 0 && skipped === 0) return "allInstalled";
+  if (update > 0 && importable === 0 && skipped === 0) return "updates";
+  if (importable > 0 && installed === 0 && update === 0 && skipped === 0)
+    return "allNew";
+  return "mixed";
+}
+
+/**
+ * The subset of a skip result that should be shown as a TRANSIENT `skipped`
+ * overlay in the bundle (so the row offers a re-import path). Only NAME-CONFLICT
+ * skips qualify: an `already-installed` skip (a concurrent-import race) has
+ * nothing to act on — re-importing the same slug would just skip again — so it
+ * must NOT be overlaid (else the row shows a misleading "Rename & install" that
+ * self-heals into a false "installed"). Pure so both reason branches are tested.
+ */
+export function nameConflictSlugs(
+  skipped: { slug: string; reason: "name-conflict" | "already-installed" }[],
+): string[] {
+  return skipped
+    .filter((s) => s.reason === "name-conflict")
+    .map((s) => s.slug);
+}
+
+/**
+ * Whether a partial-import result should offer the "Rename & install" action:
+ * only when at least one skip is a name conflict (renameable). An
+ * `already-installed`-only partial is informational.
+ */
+export function partialOffersRename(
+  skipped: { reason: "name-conflict" | "already-installed" }[],
+): boolean {
+  return skipped.some((s) => s.reason === "name-conflict");
+}
+
+/**
+ * For a role NOT installed in the current `language`, find a workspace role with
+ * the same catalog `slug` installed under a DIFFERENT language, and return that
+ * language. Drives the "installed in another language" hint (Р5): a different
+ * language of the same slug is a separate install and appears as `import`.
+ */
+export function installedLangForRole(
+  slug: string,
+  workspaceRoles: IAiRole[],
+  language: string,
+): string | undefined {
+  const other = workspaceRoles.find(
+    (r) =>
+      r.source?.slug === slug &&
+      !!r.source?.language &&
+      r.source.language !== language,
+  );
+  return other?.source?.language;
+}
+
+/**
+ * Map one catalog role to the view model, computing its install status against
+ * the workspace roles (via `catalogRoleInstallState`) and, for importable roles,
+ * the other-language hint.
+ */
+export function mapCatalogRoleToView(
+  role: IAiRoleCatalogRole,
+  workspaceRoles: IAiRole[],
+  language: string,
+): CatalogViewRole {
+  const state = catalogRoleInstallState(role, workspaceRoles, language);
+  const base = {
+    slug: role.slug,
+    emoji: role.emoji ?? undefined,
+    name: role.name,
+    description: role.description ?? "",
+  };
+  if (state.state === "update") {
+    return {
+      ...base,
+      status: "update",
+      version: state.fromVersion,
+      newVersion: state.toVersion,
+      installedRoleId: state.installed.id,
+    };
+  }
+  if (state.state === "installed") {
+    return {
+      ...base,
+      status: "installed",
+      version: role.version,
+      installedRoleId: state.installed.id,
+    };
+  }
+  return {
+    ...base,
+    status: "import",
+    version: role.version,
+    installedLang: installedLangForRole(role.slug, workspaceRoles, language),
+  };
+}
+
+/**
+ * Map a whole bundle's catalog roles to the view model, preserving order.
+ */
+export function mapBundleRolesToView(
+  roles: IAiRoleCatalogRole[],
+  workspaceRoles: IAiRole[],
+  language: string,
+): CatalogViewRole[] {
+  return roles.map((r) => mapCatalogRoleToView(r, workspaceRoles, language));
+}

apps/server/package.json

@@ -23,7 +23,7 @@
     "migration:reset": "tsx src/database/migrate.ts down-to NO_MIGRATIONS",
     "migration:codegen": "kysely-codegen --dialect=postgres --camel-case --env-file=../../.env --out-file=./src/database/types/db.d.ts",
     "lint": "eslint \"{src,apps,libs,test}/**/*.ts\" --fix",
-    "pretest": "pnpm --filter @docmost/editor-ext build",
+    "pretest": "pnpm --filter @docmost/editor-ext build && pnpm --filter @docmost/prosemirror-markdown build",
     "test": "jest",
     "test:int": "jest --config test/jest-integration.json",
     "test:watch": "jest --watch",
@@ -43,6 +43,7 @@
     "@clickhouse/client": "^1.18.2",
     "@docmost/mcp": "workspace:*",
     "@docmost/pdf-inspector": "1.9.6",
+    "@docmost/prosemirror-markdown": "workspace:*",
     "@fastify/cookie": "^11.0.2",
     "@fastify/multipart": "^10.0.0",
     "@fastify/static": "^9.1.3",
@@ -175,7 +176,7 @@
       "/node_modules/"
     ],
     "transform": {
-      "happy-dom.+\\.js$": [
+      "(happy-dom.+|prosemirror-markdown/build/.+)\\.js$": [
         "babel-jest",
         {
           "presets": [
@@ -193,7 +194,7 @@
       "^.+\\.(t|j)sx?$": "ts-jest"
     },
     "transformIgnorePatterns": [
-      "/node_modules/(?!(\\.pnpm/)?(nanoid|uuid|image-dimensions|marked|happy-dom|lib0)(@|/))"
+      "/node_modules/(?!(\\.pnpm/)?(nanoid|uuid|image-dimensions|marked|happy-dom|lib0|@docmost/prosemirror-markdown)(@|/))"
     ],
     "collectCoverageFrom": [
       "**/*.(t|j)s"
@@ -204,7 +205,8 @@
       "^@docmost/db/(.*)$": "<rootDir>/database/$1",
       "^@docmost/transactional/(.*)$": "<rootDir>/integrations/transactional/$1",
       "^@docmost/ee/(.*)$": "<rootDir>/ee/$1",
-      "^src/(.*)$": "<rootDir>/$1"
+      "^src/(.*)$": "<rootDir>/$1",
+      "^@tiptap/react$": "<rootDir>/../test/stubs/tiptap-react.js"
     }
   }
 }

apps/server/src/collaboration/collaboration.util.ts

@@ -43,7 +43,6 @@ import {
   Column,
   Status,
   addUniqueIdsToDoc,
-  htmlToMarkdown,
   TransclusionSource,
   TransclusionReference,
   FootnoteReference,
@@ -51,6 +50,7 @@ import {
   FootnoteDefinition,
   PageEmbed,
 } from '@docmost/editor-ext';
+import { convertProseMirrorToMarkdown } from '@docmost/prosemirror-markdown';
 import { generateText, getSchema, JSONContent } from '@tiptap/core';
 import { generateHTML, generateJSON } from '../common/helpers/prosemirror/html';
 // @tiptap/html library works best for generating prosemirror json state but not HTML
@@ -239,6 +239,10 @@ export function prosemirrorNodeToYElement(node: any): Y.XmlElement | Y.XmlText {
 }
 
 export function jsonToMarkdown(tiptapJson: any): string {
-  const html = jsonToHtml(tiptapJson);
-  return htmlToMarkdown(html);
+  // Direct ProseMirror JSON -> Markdown via the canonical converter
+  // (`@docmost/prosemirror-markdown`) — no HTML intermediate, no second
+  // editor-ext markdown layer. Same serializer as the page/space export and the
+  // git-sync vault writer, so every server PM->MD path emits identical canonical
+  // markdown (issue #345).
+  return convertProseMirrorToMarkdown(tiptapJson);
 }

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

@@ -610,6 +610,63 @@ describe('AiAgentRolesService guards', () => {
       expect(repo.insert.mock.calls[0][0].name).toBe('Researcher (2)');
     });
 
+    it('createdRoles lists the installed role (no renamedTo when not renamed)', async () => {
+      const { service } = makeImportService({});
+      const res = await service.importFromCatalog('ws-1', 'u1', dto());
+      expect(res.createdRoles).toEqual([
+        { slug: 'researcher', name: 'Researcher' },
+      ]);
+      expect(res.skippedRoles).toEqual([]);
+    });
+
+    it('createdRoles carries renamedTo on a rename', async () => {
+      const existing = [makeRow({ id: 'r-x', name: 'Researcher' })];
+      const { service } = makeImportService({ existing });
+      const res = await service.importFromCatalog(
+        'ws-1',
+        'u1',
+        dto({ conflict: 'rename' }),
+      );
+      expect(res.createdRoles).toEqual([
+        { slug: 'researcher', name: 'Researcher', renamedTo: 'Researcher (2)' },
+      ]);
+      expect(res.skippedRoles).toEqual([]);
+    });
+
+    it('skippedRoles: already-installed slug carries reason "already-installed"', async () => {
+      const existing = [
+        makeRow({
+          id: 'r-existing',
+          name: 'Old researcher',
+          source: { slug: 'researcher', language: 'en', version: 1 } as never,
+        }),
+      ];
+      const { service } = makeImportService({ existing });
+      const res = await service.importFromCatalog('ws-1', 'u1', dto());
+      expect(res.skippedRoles).toEqual([
+        {
+          slug: 'researcher',
+          name: 'Researcher',
+          reason: 'already-installed',
+        },
+      ]);
+      expect(res.createdRoles).toEqual([]);
+    });
+
+    it('skippedRoles: a name collision under conflict:skip carries reason "name-conflict"', async () => {
+      const existing = [makeRow({ id: 'r-x', name: 'Researcher' })];
+      const { service } = makeImportService({ existing });
+      const res = await service.importFromCatalog(
+        'ws-1',
+        'u1',
+        dto({ conflict: 'skip' }),
+      );
+      expect(res.skippedRoles).toEqual([
+        { slug: 'researcher', name: 'Researcher', reason: 'name-conflict' },
+      ]);
+      expect(res.createdRoles).toEqual([]);
+    });
+
     it('dto.slugs filters; an unknown slug becomes an error entry', async () => {
       const { service, repo } = makeImportService({
         bundleRoles: [catalogRole()],
@@ -677,6 +734,15 @@ describe('AiAgentRolesService guards', () => {
       // 'a' converged on the concurrent install (skip); 'b' imported; no errors.
       expect(res).toMatchObject({ created: 1, skipped: 1, renamed: 0 });
       expect(res.errors).toEqual([]);
+      // The per-role list records 'a' as an already-installed skip (the UI reads
+      // skippedRoles, not the counter, to render its plaque — assert the array,
+      // not just the count).
+      expect(res.skippedRoles).toContainEqual({
+        slug: 'a',
+        name: 'A',
+        reason: 'already-installed',
+      });
+      expect(res.createdRoles.map((r) => r.slug)).toEqual(['b']);
       // Both inserts were attempted (the batch did not abort on the 23505).
       expect(repo.insert).toHaveBeenCalledTimes(2);
     });

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

@@ -305,6 +305,16 @@ export class AiAgentRolesService {
     skipped: number;
     renamed: number;
     errors: { slug: string; message: string }[];
+    // Per-role lists alongside the counters (kept for back-compat). The redesigned
+    // catalog UI needs the actual roles — which were created (and any rename) and
+    // which were skipped and why — to render an inline result plaque with the
+    // conflicting role's name and a "Rename & install" affordance.
+    createdRoles: { slug: string; name: string; renamedTo?: string }[];
+    skippedRoles: {
+      slug: string;
+      name: string;
+      reason: 'name-conflict' | 'already-installed';
+    }[];
   }> {
     const { file, versions } = await this.loadBundleById(
       dto.bundleId,
@@ -312,6 +322,13 @@ export class AiAgentRolesService {
     );
 
     const errors: { slug: string; message: string }[] = [];
+    const createdRoles: { slug: string; name: string; renamedTo?: string }[] =
+      [];
+    const skippedRoles: {
+      slug: string;
+      name: string;
+      reason: 'name-conflict' | 'already-installed';
+    }[] = [];
 
     // Resolve the selected catalog roles (honor dto.slugs; flag unknown ones).
     let selected = file.roles;
@@ -351,16 +368,27 @@ export class AiAgentRolesService {
       // Already installed from the catalog in THIS language => skip (use
       // update-from-catalog). A different language of the same slug still imports.
       const installKey = `${role.slug}:${dto.language}`;
+      const originalName = role.name.trim();
       if (installedKeys.has(installKey)) {
         skipped++;
+        skippedRoles.push({
+          slug: role.slug,
+          name: originalName,
+          reason: 'already-installed',
+        });
         continue;
       }
 
-      let name = role.name.trim();
+      let name = originalName;
       let didRename = false;
       if (takenNames.has(name.toLowerCase())) {
         if (dto.conflict === 'skip') {
           skipped++;
+          skippedRoles.push({
+            slug: role.slug,
+            name: originalName,
+            reason: 'name-conflict',
+          });
           continue;
         }
         // conflict === 'rename': find a free " (N)" suffix.
@@ -380,6 +408,11 @@ export class AiAgentRolesService {
         });
         created++;
         if (didRename) renamed++;
+        createdRoles.push({
+          slug: role.slug,
+          name: originalName,
+          ...(didRename ? { renamedTo: name } : {}),
+        });
         takenNames.add(name.toLowerCase());
         installedKeys.add(installKey);
       } catch (err) {
@@ -391,6 +424,11 @@ export class AiAgentRolesService {
         // skipped (already installed) and continue; do NOT abort or error.
         if (isSourceUniqueViolation(err)) {
           skipped++;
+          skippedRoles.push({
+            slug: role.slug,
+            name: originalName,
+            reason: 'already-installed',
+          });
           installedKeys.add(installKey);
           continue;
         }
@@ -407,7 +445,7 @@ export class AiAgentRolesService {
       }
     }
 
-    return { created, skipped, renamed, errors };
+    return { created, skipped, renamed, errors, createdRoles, skippedRoles };
   }
 
   /**

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

@@ -52,7 +52,9 @@ import {
   INTERNAL_LINK_REGEX,
   extractPageSlugId,
 } from '../../../integrations/export/utils';
-import { markdownToHtml, canonicalizeFootnotes } from '@docmost/editor-ext';
+import { canonicalizeFootnotes } from '@docmost/editor-ext';
+import { markdownToProseMirror } from '@docmost/prosemirror-markdown';
+import { normalizeForeignMarkdown } from '../../../integrations/import/utils/foreign-markdown';
 import { WatcherService } from '../../watcher/watcher.service';
 import { sql } from 'kysely';
 import { TransclusionService } from '../transclusion/transclusion.service';
@@ -1301,8 +1303,14 @@ export class PageService {
 
     switch (format) {
       case 'markdown': {
-        const html = await markdownToHtml(content as string);
-        prosemirrorJson = htmlToJson(html as string);
+        // Canonical markdown -> ProseMirror JSON directly via
+        // `@docmost/prosemirror-markdown` (issue #345) — no HTML intermediate,
+        // no editor-ext markdown layer. Foreign markdown surfaces the strict
+        // parser rejects (GFM `[^id]` reference footnotes) are normalized to the
+        // canonical inline form first.
+        prosemirrorJson = await markdownToProseMirror(
+          normalizeForeignMarkdown(content as string),
+        );
         break;
       }
       case 'html': {

apps/server/src/database/migrate.ts

@@ -24,6 +24,10 @@ const migrator = new Migrator({
     path,
     migrationFolder,
   }),
+  // Match the startup auto-migrator (migration.service.ts): a back-dated
+  // migration from a long-lived branch must be applied, not rejected as
+  // "corrupted migrations" (incident #361). See that file for the full rationale.
+  allowUnorderedMigrations: true,
 });
 
 run(db, migrator, migrationFolder);

apps/server/src/database/services/migration.service.ts

@@ -19,6 +19,16 @@ export class MigrationService {
         path,
         migrationFolder: path.join(__dirname, '..', 'migrations'),
       }),
+      // A long-lived branch can add a migration whose timestamped filename sorts
+      // BEFORE migrations already applied in prod (e.g. #234's 20260627 landing
+      // after 20260704 was live). With the default (ordered) setting the startup
+      // migrator then sees "corrupted migrations" — the applied set is no longer a
+      // prefix of the sorted list — throws, and the app crash-loops on boot
+      // (incident #361: 502s for ~11 min). allowUnorderedMigrations runs any
+      // not-yet-applied migration regardless of filename order, so a back-dated
+      // migration is applied instead of bricking startup. A CI order-gate still
+      // discourages back-dating; this is the runtime safety net.
+      allowUnorderedMigrations: true,
     });
 
     const { error, results } = await migrator.migrateToLatest();

apps/server/src/integrations/ai/ai-sdk-partial-output.patch.spec.ts

@@ -0,0 +1,124 @@
+import { readFileSync } from 'fs';
+import { streamText, Output } from 'ai';
+import { MockLanguageModelV3, simulateReadableStream } from 'ai/test';
+
+/**
+ * Regression tests for patches/ai@6.0.134.patch (server heap OOM on long
+ * autonomous agent runs, #184).
+ *
+ * Unpatched ai@6.0.134 substitutes the default text() output strategy even
+ * when the caller passes NO `output` option. Its createOutputTransformStream
+ * then accumulates the ENTIRE turn text and, on EVERY text-delta, enqueues a
+ * flat snapshot of all text so far as `partialOutput` (O(n^2) memory). Those
+ * snapshots pile up in the never-consumed leftover tee() branch of
+ * DefaultStreamTextResult.baseStream, which is what OOM'd production during a
+ * ~28k-chunk agent turn. The pnpm patch skips partialOutput production
+ * entirely when no output strategy was requested, while keeping per-delta
+ * streaming granularity.
+ */
+describe('ai@6.0.134 pnpm patch: no partialOutput accumulation without an output strategy', () => {
+  const makeModel = () =>
+    new MockLanguageModelV3({
+      doStream: async () => ({
+        stream: simulateReadableStream({
+          chunks: [
+            { type: 'stream-start' as const, warnings: [] },
+            { type: 'text-start' as const, id: '1' },
+            { type: 'text-delta' as const, id: '1', delta: 'Hello' },
+            { type: 'text-delta' as const, id: '1', delta: ', ' },
+            { type: 'text-delta' as const, id: '1', delta: 'world!' },
+            { type: 'text-end' as const, id: '1' },
+            {
+              type: 'finish' as const,
+              finishReason: { unified: 'stop' as const, raw: 'stop' },
+              usage: {
+                inputTokens: {
+                  total: 1,
+                  noCache: undefined,
+                  cacheRead: undefined,
+                  cacheWrite: undefined,
+                },
+                outputTokens: { total: 1, text: 1, reasoning: undefined },
+              },
+            },
+          ],
+        }),
+      }),
+    });
+
+  it('preserves per-delta streaming granularity in textStream', async () => {
+    const result = streamText({ model: makeModel(), prompt: 'hi' });
+
+    const deltas: string[] = [];
+    for await (const delta of result.textStream) {
+      deltas.push(delta);
+    }
+
+    // The patch must NOT coalesce or drop deltas: three model deltas arrive
+    // as three separate textStream chunks.
+    expect(deltas).toEqual(['Hello', ', ', 'world!']);
+  });
+
+  it('emits NO partialOutput values when the caller did not request an output strategy', async () => {
+    const result = streamText({ model: makeModel(), prompt: 'hi' });
+
+    // Fully consume the primary stream first (mirrors production usage).
+    for await (const _ of result.textStream) {
+      // drain
+    }
+
+    const partials: unknown[] = [];
+    for await (const partial of result.experimental_partialOutputStream) {
+      partials.push(partial);
+    }
+
+    // TRIPWIRE: on unpatched ai@6.0.134 the default text() output strategy
+    // yields one cumulative partial per text-delta here (['Hello', 'Hello, ',
+    // 'Hello, world!']). An empty stream proves the patch is applied and no
+    // cumulative snapshots are being produced (and thus none can pile up in
+    // the leftover internal tee branch).
+    expect(partials).toEqual([]);
+  });
+
+  it('preserves cumulative partialOutput when the caller DOES request an output strategy', async () => {
+    // PRESERVE-BRANCH GUARD: the patch only short-circuits partialOutput when
+    // `output == null`. When an output strategy IS set (here Output.text()),
+    // createOutputTransformStream must fall through to the ORIGINAL code path
+    // and keep publishing cumulative snapshots, so object/text-output consumers
+    // behave byte-identically to unpatched ai. A careless re-port that routed
+    // output-set calls into the skip branch would leave partialOutput empty and
+    // silently break those consumers — this test is the tripwire for that.
+    const result = streamText({
+      model: makeModel(),
+      prompt: 'hi',
+      experimental_output: Output.text(),
+    });
+
+    // Drain the primary stream fully and accumulate the complete output text.
+    let fullText = '';
+    for await (const delta of result.textStream) {
+      fullText += delta;
+    }
+
+    const partials: string[] = [];
+    for await (const partial of result.experimental_partialOutputStream) {
+      partials.push(partial);
+    }
+
+    // With a strategy set, partialOutput must be PRESERVED (non-empty) and
+    // cumulative: the last emitted partial equals the full accumulated text.
+    expect(partials.length).toBeGreaterThan(0);
+    expect(partials[partials.length - 1]).toBe(fullText);
+    expect(fullText).toBe('Hello, world!');
+  });
+
+  it('both installed dist builds (CJS and ESM) carry the patch marker', () => {
+    // Secondary guard: pins the patch to BOTH bundles the SDK ships, since
+    // the NestJS server consumes CJS while other tooling may load ESM.
+    const cjsPath = require.resolve('ai');
+    const mjsPath = cjsPath.replace(/index\.js$/, 'index.mjs');
+    expect(cjsPath).toMatch(/index\.js$/);
+    expect(readFileSync(cjsPath, 'utf8')).toContain('PATCH(docmost');
+    expect(readFileSync(mjsPath, 'utf8')).toContain('PATCH(docmost');
+  });
+});

apps/server/src/integrations/export/export-markdown.spec.ts

@@ -0,0 +1,145 @@
+// export.service.ts imports the ESM-only @sindresorhus/slugify (not in jest's
+// transform allowlist). It is irrelevant to the markdown-serialization path under
+// test (only used for page-mention link slugs on the DB path), so it is mocked
+// out to keep the module graph loadable under ts-jest (mirrors the import specs).
+jest.mock('@sindresorhus/slugify', () => ({
+  __esModule: true,
+  default: (input: string) => String(input),
+}));
+
+import { convertProseMirrorToMarkdown } from '@docmost/prosemirror-markdown';
+import { ExportService } from './export.service';
+import { ExportFormat } from './dto/export-dto';
+
+/**
+ * STEP 1 golden test for issue #345: server MARKDOWN export runs DIRECTLY through
+ * the canonical converter (`convertProseMirrorToMarkdown`) — no HTML intermediate
+ * and no `@docmost/editor-ext` markdown layer — so the emitted markdown is in the
+ * canonical package forms and is byte-identical to the git-sync vault body.
+ *
+ * These are the goldens the swap has to satisfy: they assert the CANONICAL
+ * surface (callout `> [!type]`, inline footnote `^[…]`, lossless image
+ * `<!--img …-->`) rather than the old editor-ext forms (`:::type`, `[^id]`,
+ * lossy `![alt](src)`).
+ *
+ * `exportPage(..., singlePage=false)` takes no DB path (no mention rewriting), so
+ * the service is constructed with null collaborators and only the pure
+ * PM -> Markdown path is exercised.
+ */
+
+function makeService(): ExportService {
+  return new ExportService(
+    null as any, // pageRepo
+    null as any, // pagePermissionRepo
+    null as any, // db
+    null as any, // storageService
+    null as any, // environmentService
+    null as any, // domainService
+  );
+}
+
+// A representative page exercising the node types whose canonical markdown form
+// changed with the move off the editor-ext layer: callout, inline footnote, and a
+// lossless image carrying width/align attrs that the old layer dropped.
+const REPRESENTATIVE_DOC = {
+  type: 'doc',
+  content: [
+    {
+      type: 'paragraph',
+      content: [
+        { type: 'text', text: 'Body ' },
+        { type: 'footnoteReference', attrs: { id: 'fn-1' } },
+        { type: 'text', text: ' end.' },
+      ],
+    },
+    {
+      type: 'callout',
+      attrs: { type: 'info', icon: null },
+      content: [
+        {
+          type: 'paragraph',
+          content: [{ type: 'text', text: 'Heads up' }],
+        },
+      ],
+    },
+    {
+      type: 'image',
+      attrs: {
+        src: '/files/pic.png',
+        alt: 'Pic',
+        width: 320,
+        align: 'left',
+      },
+    },
+    {
+      type: 'footnotesList',
+      content: [
+        {
+          type: 'footnoteDefinition',
+          attrs: { id: 'fn-1' },
+          content: [
+            {
+              type: 'paragraph',
+              content: [{ type: 'text', text: 'the note' }],
+            },
+          ],
+        },
+      ],
+    },
+  ],
+};
+
+describe('ExportService — markdown export via the canonical converter (#345)', () => {
+  it('emits canonical callout, inline footnote and lossless image forms', async () => {
+    const service = makeService();
+    const md = (await service.exportPage(ExportFormat.Markdown, {
+      title: '',
+      content: REPRESENTATIVE_DOC,
+    } as any)) as string;
+
+    // Callout: Obsidian `> [!type]`, NOT the legacy `:::type`.
+    expect(md).toContain('> [!info]');
+    expect(md).not.toContain(':::');
+
+    // Inline footnote: `^[…]`, NOT the reference `[^id]` form.
+    expect(md).toContain('^[the note]');
+    expect(md).not.toMatch(/\[\^/);
+
+    // Lossless image: trailing `<!--img …-->` carrying the dropped attrs.
+    expect(md).toContain('![Pic](/files/pic.png)');
+    expect(md).toContain('<!--img');
+    expect(md).toContain('"width":"320"');
+    expect(md).toContain('"align":"left"');
+  });
+
+  it('export body is byte-identical to the git-sync vault serializer (export == vault)', async () => {
+    const service = makeService();
+    // A title-less page: exportPage prepends NO heading, so the whole output is
+    // the page BODY — exactly what git-sync serializes (git-sync stores the title
+    // in frontmatter / the filename, never as an in-body H1).
+    const exported = (await service.exportPage(ExportFormat.Markdown, {
+      title: '',
+      content: REPRESENTATIVE_DOC,
+    } as any)) as string;
+
+    // The git-sync vault writer feeds this SAME converter (git-sync
+    // `stabilizePageBody` = convertProseMirrorToMarkdown(content) at the
+    // fixpoint). For an already-stable doc the single pass IS the fixpoint, so
+    // the two are byte-identical by construction — assert it.
+    const vaultBody = convertProseMirrorToMarkdown(REPRESENTATIVE_DOC);
+    expect(exported).toBe(vaultBody);
+  });
+
+  it('prepends the page title as an H1 heading (the one documented export/vault delta)', async () => {
+    const service = makeService();
+    const md = (await service.exportPage(ExportFormat.Markdown, {
+      title: 'My Page',
+      content: { type: 'doc', content: [] },
+    } as any)) as string;
+
+    // Export makes standalone files, so it prepends the title as an H1. This is
+    // the ONE deliberate difference from the vault body (which carries the title
+    // in frontmatter). The body below the heading still serializes canonically.
+    expect(md.startsWith('# My Page')).toBe(true);
+  });
+});

apps/server/src/integrations/export/export.service.ts

@@ -37,7 +37,7 @@ import {
   getAttachmentIds,
   getProsemirrorContent,
 } from '../../common/helpers/prosemirror/utils';
-import { htmlToMarkdown } from '@docmost/editor-ext';
+import { convertProseMirrorToMarkdown } from '@docmost/prosemirror-markdown';
 
 type AllowedAttachment = { id: string; fileName: string; filePath: string };
 
@@ -79,9 +79,8 @@ export class ExportService {
       prosemirrorJson.content.unshift(titleNode);
     }
 
-    const pageHtml = jsonToHtml(prosemirrorJson);
-
     if (format === ExportFormat.HTML) {
+      const pageHtml = jsonToHtml(prosemirrorJson);
       return `<!DOCTYPE html>
       <html>
         <head>
@@ -92,11 +91,14 @@ export class ExportService {
     }
 
     if (format === ExportFormat.Markdown) {
-      const newPageHtml = pageHtml.replace(
-        /<colgroup[^>]*>[\s\S]*?<\/colgroup>/gim,
-        '',
-      );
-      return htmlToMarkdown(newPageHtml);
+      // Direct ProseMirror JSON -> Markdown via the canonical converter
+      // (`@docmost/prosemirror-markdown`). This is the SAME serializer the
+      // git-sync vault writer feeds (see git-sync `stabilizePageBody`), so an
+      // exported page body is byte-identical to its vault representation — no
+      // HTML intermediate, no second markdown layer, no format drift (issue
+      // #345). The old `<colgroup>` scrub is gone with the HTML step: the
+      // converter emits GFM tables directly and never produces `<colgroup>`.
+      return convertProseMirrorToMarkdown(prosemirrorJson);
     }
 
     return;

apps/server/src/integrations/import/services/file-import-task.service.footnote-canonicalize.spec.ts

@@ -17,6 +17,22 @@ jest.mock('image-dimensions', () => ({
   __esModule: true,
   imageDimensionsFromData: () => undefined,
 }));
+// FileImportTaskService -> PageService -> collaboration.gateway ->
+// metrics.registry imports `prom-client`, which is not resolvable in this
+// workspace's node_modules (types-only stub, no runtime entry). Metrics are
+// disabled on this path, so a virtual no-op mock keeps the module graph loadable.
+jest.mock(
+  'prom-client',
+  () => ({
+    collectDefaultMetrics: () => undefined,
+    Registry: class {},
+    Histogram: class {},
+    Gauge: class {},
+    Counter: class {},
+    Summary: class {},
+  }),
+  { virtual: true },
+);
 
 import { promises as fs } from 'fs';
 import * as os from 'os';
@@ -26,14 +42,17 @@ import { ImportService } from './import.service';
 
 /**
  * Binding test for issue #228 / review #5: FileImportTaskService.processGenericImport
- * is a NON-editor write path (markdownToHtml -> processHTML -> JSON, never runs
- * footnoteSyncPlugin), so it canonicalizes footnotes before persisting. This pins
- * that binding — the same one import.service has a spec for — which previously had
- * NO spec at all.
+ * is a NON-editor write path, so a zip-imported `.md` page ends up with canonical
+ * footnotes before persisting: ordered by first reference, reused refs deduped,
+ * orphan definitions dropped.
  *
- * The markdown -> HTML -> ProseMirror conversion is REAL (a real ImportService,
- * its createYdoc stubbed); the filesystem is a real temp dir with one .md file;
- * the DB transaction is stubbed to capture the persisted page content.
+ * Since #345 the `.md` parse runs `normalizeForeignMarkdown` ->
+ * `markdownToProseMirror` -> `jsonToHtml` (feeding the shared HTML attachment /
+ * link pipeline) -> `processHTML` -> `canonicalizeFootnotes`. The parser assigns
+ * fresh `fn-*` ids, so we assert by definition BODY order rather than the source
+ * labels. The conversion is REAL (a real ImportService, its createYdoc stubbed);
+ * the filesystem is a real temp dir with one .md file; the DB transaction is
+ * stubbed to capture the persisted page content.
  */
 
 // Out-of-order references (c, a, b), a REUSED reference ([^a] twice), and an
@@ -49,13 +68,14 @@ const MARKDOWN = [
   '[^z]: orphan note',
 ].join('\n');
 
-function footnoteListIds(content: any): string[] {
+/** Definition body texts of the (single) footnotesList, in list order. */
+function footnoteListBodies(content: any): string[] {
   const list = (content?.content ?? []).find(
     (n: any) => n.type === 'footnotesList',
   );
   return (list?.content ?? [])
     .filter((n: any) => n.type === 'footnoteDefinition')
-    .map((n: any) => n.attrs?.id);
+    .map((n: any) => n.content?.[0]?.content?.[0]?.text);
 }
 
 // A permissive chainable stub for the spaces lookup (selectFrom(...).select(...)
@@ -71,80 +91,127 @@ function chainable(result: any): any {
   return proxy;
 }
 
+/**
+ * Run one markdown file through the REAL zip-import pipeline
+ * (`processGenericImport` -> `markdownToProseMirror` -> `jsonToHtml` ->
+ * `processHTML`/`htmlToJson`) and return the persisted page `content`. This is
+ * the server-specific PM->HTML->PM hop that the package's own PM<->MD tests do
+ * NOT cover.
+ */
+async function runZipImport(markdown: string): Promise<any> {
+  const extractDir = await fs.mkdtemp(path.join(os.tmpdir(), 'fit-canon-'));
+  await fs.writeFile(path.join(extractDir, 'note.md'), markdown, 'utf-8');
+
+  const importService = new ImportService(
+    {} as any,
+    {} as any,
+    {} as any,
+    {} as any,
+  );
+  jest
+    .spyOn(importService as any, 'createYdoc')
+    .mockResolvedValue(Buffer.from([]) as any);
+
+  let captured: any = null;
+  const trx = {
+    insertInto: (table: string) => ({
+      values: (v: any) => {
+        if (table === 'pages') captured = v;
+        return { execute: async () => {} };
+      },
+    }),
+  };
+  const db: any = {
+    selectFrom: () => chainable({ slug: 'space-slug' }),
+    transaction: () => ({ execute: (fn: any) => fn(trx) }),
+  };
+
+  const importAttachmentService = {
+    processAttachments: async ({ html }: any) => html,
+  };
+  const service = new FileImportTaskService(
+    {} as any, // storageService
+    importService as any,
+    { nextPagePosition: async () => 'a0' } as any,
+    { insertBacklink: jest.fn() } as any,
+    db,
+    importAttachmentService as any,
+    { emit: jest.fn() } as any,
+    { logBatchWithContext: jest.fn() } as any,
+  );
+
+  const fileTask: any = {
+    id: 'task-1',
+    source: 'generic',
+    spaceId: 'space-1',
+    workspaceId: 'ws-1',
+    creatorId: 'user-1',
+  };
+
+  try {
+    await service.processGenericImport({ extractDir, fileTask });
+    expect(captured).toBeTruthy();
+    return captured.content;
+  } finally {
+    await fs.rm(extractDir, { recursive: true, force: true });
+  }
+}
+
+/** Find the first node of a given type anywhere in a PM content tree. */
+function findFirst(node: any, type: string): any {
+  if (!node || typeof node !== 'object') return null;
+  if (node.type === type) return node;
+  for (const child of node.content ?? []) {
+    const hit = findFirst(child, type);
+    if (hit) return hit;
+  }
+  return null;
+}
+
 describe('FileImportTaskService.processGenericImport — footnote canonicalization (#228)', () => {
   it('orders footnotes by first reference, dedupes reuse, and drops orphans on zip import', async () => {
-    const extractDir = await fs.mkdtemp(path.join(os.tmpdir(), 'fit-canon-'));
-    await fs.writeFile(path.join(extractDir, 'note.md'), MARKDOWN, 'utf-8');
-
-    // Real ImportService for the html -> JSON conversion; stub the yjs encode.
-    const importService = new ImportService(
-      {} as any,
-      {} as any,
-      {} as any,
-      {} as any,
+    const content = await runZipImport(MARKDOWN);
+    // Definitions ordered by FIRST REFERENCE (C, A, B), NOT the markdown
+    // definition order (A, B, C). Ids are the parser's fresh `fn-*`, so pin
+    // the BODIES.
+    expect(footnoteListBodies(content)).toEqual(['note C', 'note A', 'note B']);
+    // Orphan [^z] dropped; reused [^a] collapses to one definition; one list.
+    expect(footnoteListBodies(content)).not.toContain('orphan note');
+    const lists = (content.content ?? []).filter(
+      (n: any) => n.type === 'footnotesList',
     );
-    jest
-      .spyOn(importService as any, 'createYdoc')
-      .mockResolvedValue(Buffer.from([]) as any);
+    expect(lists).toHaveLength(1);
+    expect(
+      footnoteListBodies(content).filter((b) => b === 'note A'),
+    ).toHaveLength(1);
+  });
 
-    let captured: any = null;
-    const trx = {
-      insertInto: (table: string) => ({
-        values: (v: any) => {
-          if (table === 'pages') captured = v;
-          return { execute: async () => {} };
-        },
-      }),
-    };
-    const db: any = {
-      selectFrom: () => chainable({ slug: 'space-slug' }),
-      transaction: () => ({ execute: (fn: any) => fn(trx) }),
-    };
+  // #345 F4: the zip path routes markdown through jsonToHtml -> processHTML ->
+  // htmlToJson (the shared HTML attachment pipeline). #345's headline is LOSSLESS
+  // image width/align via the `<!--img {...}-->` comment; a callout carries its
+  // `type`. This asserts those survive the PM->HTML->PM hop — the one hop the
+  // package's PM<->MD suite does not exercise.
+  it('preserves image width/align and callout type through the PM->HTML->PM hop', async () => {
+    const md = [
+      '# Doc',
+      '',
+      '![a picture](https://example.com/i.png) <!--img {"width":"320","align":"left"}-->',
+      '',
+      ':::warning',
+      'Careful now.',
+      ':::',
+    ].join('\n');
 
-    const importAttachmentService = {
-      processAttachments: async ({ html }: any) => html,
-    };
-    const backlinkRepo = { insertBacklink: jest.fn() };
-    const eventEmitter = { emit: jest.fn() };
-    const auditService = { logBatchWithContext: jest.fn() };
+    const content = await runZipImport(md);
 
-    const pageService = { nextPagePosition: async () => 'a0' };
+    const image = findFirst(content, 'image');
+    expect(image).toBeTruthy();
+    // The lossless sizing/alignment must survive the HTML hop.
+    expect(String(image.attrs?.width)).toBe('320');
+    expect(image.attrs?.align).toBe('left');
 
-    const service = new FileImportTaskService(
-      {} as any, // storageService
-      importService as any,
-      pageService as any,
-      backlinkRepo as any,
-      db,
-      importAttachmentService as any,
-      eventEmitter as any,
-      auditService as any,
-    );
-
-    const fileTask: any = {
-      id: 'task-1',
-      source: 'generic',
-      spaceId: 'space-1',
-      workspaceId: 'ws-1',
-      creatorId: 'user-1',
-    };
-
-    try {
-      await service.processGenericImport({ extractDir, fileTask });
-
-      expect(captured).toBeTruthy();
-      const content = captured.content;
-      // Reference order is c, a, b (NOT the markdown definition order a, b, c).
-      expect(footnoteListIds(content)).toEqual(['c', 'a', 'b']);
-      // Orphan [^z] dropped; reused [^a] collapses to one definition; one list.
-      expect(footnoteListIds(content)).not.toContain('z');
-      const lists = (content.content ?? []).filter(
-        (n: any) => n.type === 'footnotesList',
-      );
-      expect(lists).toHaveLength(1);
-      expect(footnoteListIds(content).filter((id) => id === 'a')).toHaveLength(1);
-    } finally {
-      await fs.rm(extractDir, { recursive: true, force: true });
-    }
+    const callout = findFirst(content, 'callout');
+    expect(callout).toBeTruthy();
+    expect(callout.attrs?.type).toBe('warning');
   });
 });

apps/server/src/integrations/import/services/file-import-task.service.ts

@@ -1,6 +1,9 @@
 import { Inject, Injectable, Logger } from '@nestjs/common';
 import * as path from 'path';
-import { jsonToText } from '../../../collaboration/collaboration.util';
+import {
+  jsonToHtml,
+  jsonToText,
+} from '../../../collaboration/collaboration.util';
 import { InjectKysely } from 'nestjs-kysely';
 import { KyselyDB } from '@docmost/db/types/kysely.types';
 import {
@@ -18,9 +21,11 @@ import { generateSlugId } from '../../../common/helpers';
 import { v7 } from 'uuid';
 import { generateJitteredKeyBetween } from 'fractional-indexing-jittered';
 import { FileTask, InsertablePage } from '@docmost/db/types/entity.types';
-import { markdownToHtml, canonicalizeFootnotes } from '@docmost/editor-ext';
+import { canonicalizeFootnotes } from '@docmost/editor-ext';
+import { markdownToProseMirror } from '@docmost/prosemirror-markdown';
 import { getProsemirrorContent } from '../../../common/helpers/prosemirror/utils';
 import { formatImportHtml } from '../utils/import-formatter';
+import { normalizeForeignMarkdown } from '../utils/foreign-markdown';
 import {
   buildAttachmentCandidates,
   collectMarkdownAndHtmlFiles,
@@ -461,7 +466,18 @@ export class FileImportTaskService {
               content = await fs.readFile(absPath, 'utf-8');
 
               if (page.fileExtension.toLowerCase() === '.md') {
-                content = await markdownToHtml(content);
+                // Parse markdown with the single canonical converter
+                // (`@docmost/prosemirror-markdown`), after normalizing foreign
+                // reference footnotes, then serialize to HTML so the shared HTML
+                // pipeline below (processAttachments + formatImportHtml +
+                // processHTML) keeps handling `.md` and `.html` imports
+                // uniformly. The markdown PARSE no longer goes through the
+                // editor-ext markdown layer (issue #345) — the drift source is
+                // gone. The PM -> HTML -> PM hop that follows is lossless
+                // plumbing for attachment/link resolution, NOT a second parse.
+                content = jsonToHtml(
+                  await markdownToProseMirror(normalizeForeignMarkdown(content)),
+                );
               }
             } catch (err: any) {
               if (err?.code === 'ENOENT') {
@@ -500,10 +516,12 @@ export class FileImportTaskService {
               this.importService.extractTitleAndRemoveHeading(pmState);
 
             // Canonicalize footnote topology on this non-editor write path
-            // (markdownToHtml/processHTML never runs footnoteSyncPlugin), so a
-            // zip-imported page's footnotes are reference-ordered, deduped, and
+            // (the HTML pipeline's processHTML never runs footnoteSyncPlugin), so
+            // a zip-imported page's footnotes are reference-ordered, deduped, and
             // orphan-free like the editor's invariant (issue #228). Pure +
-            // idempotent + shape-safe; a footnote-free doc is unchanged.
+            // idempotent + shape-safe; a footnote-free doc is unchanged. (For a
+            // `.md` file the package parser already yields canonical footnotes,
+            // so this is a no-op there.)
             // (Future consolidation, architecture B: like import.service, this
             // path persists directly rather than via PageService — a shared
             // "prepare JSON for persist" helper would centralize this call.)

apps/server/src/integrations/import/services/import.service.footnote-canonicalize.spec.ts

@@ -12,13 +12,19 @@ import { canonicalizeFootnotes } from '@docmost/editor-ext';
 
 /**
  * Integration-ish test for the USER-FACING markdown import path
- * (`ImportService.importPage`). It exercises the REAL markdown -> HTML -> JSON
- * conversion and asserts that the stored page content has its footnotes
- * canonicalized — the gap that issue #228 fixes: the import path builds
- * ProseMirror JSON directly (never running the editor's footnoteSyncPlugin), so
- * before this wiring the stored footnotes kept the markdown's physical
- * definition order (out of order vs. references), retained orphan definitions,
- * and did not collapse reused references.
+ * (`ImportService.importPage`). It exercises the REAL markdown -> ProseMirror
+ * conversion and asserts the stored page's footnotes are canonical: ordered by
+ * FIRST REFERENCE (not markdown definition order), reused references deduped to a
+ * single definition, and orphan definitions dropped.
+ *
+ * Since #345 the markdown parse runs through the canonical package
+ * (`normalizeForeignMarkdown` -> `markdownToProseMirror`), which owns this
+ * canonicalization: the input's GFM `[^id]` reference footnotes are normalized to
+ * inline `^[…]`, and the parser assigns fresh sequential ids (`fn-*`) in
+ * reference order while merging identical bodies — so we assert by definition
+ * BODY order, not by the source labels. `canonicalizeFootnotes` remains wired as
+ * an idempotent safety net (issue #228) and is a no-op on this already-canonical
+ * output.
  *
  * The DB/ydoc side-effects are stubbed: `getNewPagePosition` (DB query) and
  * `createYdoc` (Yjs encode) are spied, and `pageRepo.insertPage` captures the
@@ -67,24 +73,14 @@ function makeService() {
 }
 
 /** List the footnote-definition ids of the (single) footnotesList, in order. */
-function footnoteListIds(content: any): string[] {
+/** Definition body texts of the (single) footnotesList, in list order. */
+function footnoteListBodies(content: any): string[] {
   const list = (content.content ?? []).find(
     (n: any) => n.type === 'footnotesList',
   );
-  if (!list) return [];
-  return (list.content ?? [])
+  return (list?.content ?? [])
     .filter((n: any) => n.type === 'footnoteDefinition')
-    .map((n: any) => n.attrs?.id);
-}
-
-function definitionText(content: any, id: string): string | undefined {
-  const list = (content.content ?? []).find(
-    (n: any) => n.type === 'footnotesList',
-  );
-  const def = (list?.content ?? []).find(
-    (n: any) => n.type === 'footnoteDefinition' && n.attrs?.id === id,
-  );
-  return def?.content?.[0]?.content?.[0]?.text;
+    .map((n: any) => n.content?.[0]?.content?.[0]?.text);
 }
 
 describe('ImportService.importPage — footnote canonicalization (#228)', () => {
@@ -101,23 +97,23 @@ describe('ImportService.importPage — footnote canonicalization (#228)', () =>
     const content = getCaptured().content;
     expect(content).toBeTruthy();
 
-    // Reference order is c, a, b (NOT the markdown definition order a, b, c).
-    expect(footnoteListIds(content)).toEqual(['c', 'a', 'b']);
-
-    // Definitions preserved and attached to the right ids.
-    expect(definitionText(content, 'c')).toBe('note C');
-    expect(definitionText(content, 'a')).toBe('note A');
-    expect(definitionText(content, 'b')).toBe('note B');
+    // Definitions ordered by FIRST REFERENCE (C, A, B) — NOT the markdown
+    // definition order (A, B, C) — with the orphan [^z] dropped and the reused
+    // [^a] collapsed to a single definition. (Ids are the parser's fresh `fn-*`,
+    // so we pin the BODIES.)
+    expect(footnoteListBodies(content)).toEqual(['note C', 'note A', 'note B']);
 
     // Orphan definition [^z] is dropped.
-    expect(footnoteListIds(content)).not.toContain('z');
+    expect(footnoteListBodies(content)).not.toContain('orphan note');
 
     // Reused [^a] yields exactly ONE definition, and exactly one list.
     const lists = (content.content ?? []).filter(
       (n: any) => n.type === 'footnotesList',
     );
     expect(lists).toHaveLength(1);
-    expect(footnoteListIds(content).filter((id) => id === 'a')).toHaveLength(1);
+    expect(
+      footnoteListBodies(content).filter((b) => b === 'note A'),
+    ).toHaveLength(1);
   });
 
   it('is idempotent: canonicalizing the stored output again is a no-op', async () => {
@@ -134,6 +130,6 @@ describe('ImportService.importPage — footnote canonicalization (#228)', () =>
     // time must not change it (safe to wire into every write path).
     const second = canonicalizeFootnotes(stored);
     expect(second).toEqual(stored);
-    expect(footnoteListIds(second)).toEqual(['c', 'a', 'b']);
+    expect(footnoteListBodies(second)).toEqual(['note C', 'note A', 'note B']);
   });
 });

apps/server/src/integrations/import/services/import.service.ts

@@ -17,7 +17,9 @@ import {
 import { generateJitteredKeyBetween } from 'fractional-indexing-jittered';
 import { TiptapTransformer } from '@hocuspocus/transformer';
 import * as Y from 'yjs';
-import { markdownToHtml, canonicalizeFootnotes } from '@docmost/editor-ext';
+import { canonicalizeFootnotes } from '@docmost/editor-ext';
+import { markdownToProseMirror } from '@docmost/prosemirror-markdown';
+import { normalizeForeignMarkdown } from '../utils/foreign-markdown';
 import {
   FileTaskStatus,
   FileTaskType,
@@ -85,11 +87,13 @@ export class ImportService {
 
     const extracted = this.extractTitleAndRemoveHeading(prosemirrorState);
     const title = extracted.title;
-    // Imported markdown/HTML is built via markdownToHtml -> htmlToJson, which
-    // never runs the editor's footnoteSyncPlugin, so the footnote topology keeps
-    // the source's PHYSICAL definition order (out of order vs. references),
-    // retains orphan definitions, and is not deduped. Canonicalize before
-    // persisting so the stored page matches the editor's invariant (issue #228).
+    // The markdown path now canonicalizes footnotes itself (the package parser),
+    // but the HTML path (processHTML -> htmlToJson) does NOT run the editor's
+    // footnoteSyncPlugin, so an imported HTML doc can keep its source's PHYSICAL
+    // definition order (out of order vs. references), retain orphan definitions,
+    // and not be deduped. Canonicalize before persisting so the stored page
+    // matches the editor's invariant (issue #228); it is an idempotent no-op on
+    // the already-canonical markdown output.
     // Pure + idempotent + shape-safe: a doc with no footnotes is unchanged.
     // (Future consolidation, architecture B: this import path persists directly
     // via pageRepo.insertPage rather than through PageService.createPage, so the
@@ -133,12 +137,15 @@ export class ImportService {
   }
 
   async processMarkdown(markdownInput: string): Promise<any> {
-    try {
-      const html = await markdownToHtml(markdownInput);
-      return this.processHTML(html);
-    } catch (err) {
-      throw err;
-    }
+    // Canonical markdown -> ProseMirror JSON directly via
+    // `@docmost/prosemirror-markdown` (issue #345) — no HTML intermediate and no
+    // second editor-ext markdown layer. Foreign markdown surfaces the strict
+    // canonical parser does not accept (GFM `[^id]` reference footnotes) are
+    // rewritten to the canonical inline form by `normalizeForeignMarkdown` first.
+    // The HTML-cleanup pass (`normalizeImportHtml`) is intentionally skipped here:
+    // it targets foreign *HTML* (Notion/XWiki), which only ever arrives on the
+    // `.html` path (`processHTML`), never as canonical markdown.
+    return markdownToProseMirror(normalizeForeignMarkdown(markdownInput));
   }
 
   async processHTML(htmlInput: string): Promise<any> {

apps/server/src/integrations/import/utils/foreign-markdown.spec.ts

@@ -0,0 +1,218 @@
+import {
+  convertProseMirrorToMarkdown,
+  markdownToProseMirror,
+} from '@docmost/prosemirror-markdown';
+import { normalizeForeignMarkdown } from './foreign-markdown';
+
+/**
+ * STEP 2 goldens for issue #345: the foreign-markdown normalizer that runs at the
+ * import boundary BEFORE the strict canonical parser (`markdownToProseMirror`).
+ *
+ * Two layers:
+ *  1. PURE string→string cases pinning the normalizer's own behavior (GFM
+ *     reference footnotes → inline `^[…]`).
+ *  2. END-TO-END acceptance: for a foreign corpus, `normalizeForeignMarkdown`
+ *     then `markdownToProseMirror` then `convertProseMirrorToMarkdown` must leave
+ *     NO literal `[^id]` / `:::` garbage in the document and must re-export in the
+ *     canonical forms.
+ */
+
+describe('normalizeForeignMarkdown — GFM reference footnotes', () => {
+  it('inlines a single-line reference footnote and drops its definition', () => {
+    const out = normalizeForeignMarkdown(
+      'A note[^1] here.\n\n[^1]: The definition.',
+    );
+    expect(out).toBe('A note^[The definition.] here.\n');
+  });
+
+  it('inlines every reference to a reused id (downstream dedups)', () => {
+    const out = normalizeForeignMarkdown(
+      'X[^a] and Y[^a].\n\n[^a]: shared.',
+    );
+    expect(out).toBe('X^[shared.] and Y^[shared.].\n');
+  });
+
+  it('joins indented continuation lines of a definition with a space', () => {
+    const out = normalizeForeignMarkdown(
+      'See[^n].\n\n[^n]: line one\n    line two',
+    );
+    expect(out).toBe('See^[line one line two].\n');
+  });
+
+  it('never rewrites a reference inside a fenced code block', () => {
+    const out = normalizeForeignMarkdown(
+      '```\ncode[^1] here\n```\n\n[^1]: def.',
+    );
+    expect(out).toContain('code[^1] here');
+    // The (now orphaned) definition line is still removed.
+    expect(out).not.toContain('[^1]: def.');
+  });
+
+  it('never rewrites a reference inside an INLINE-code span (backticks)', () => {
+    // The `[^1]` inside backticks is literal code and must survive verbatim;
+    // the one outside is rewritten. (Bug #1: only fenced blocks were protected.)
+    const out = normalizeForeignMarkdown(
+      'Use `arr[^1]` in code but note[^1] in prose.\n\n[^1]: def.',
+    );
+    expect(out).toBe('Use `arr[^1]` in code but note^[def.] in prose.\n');
+  });
+
+  it('escapes brackets in a body so an unbalanced ] cannot truncate the footnote', () => {
+    // A foreign definition body with a stray `]` would, unescaped, close the
+    // canonical `^[...]` early and leak the tail as text (bug #2). The body's
+    // brackets are backslash-escaped so the footnote stays whole.
+    const out = normalizeForeignMarkdown(
+      'Ref[^1] here.\n\n[^1]: see item ] and [more] later',
+    );
+    expect(out).toBe('Ref^[see item \\] and \\[more\\] later] here.\n');
+    // The tokenizer must see exactly one unescaped closing bracket (our own).
+    expect(out.match(/(?<!\\)\]/g)).toHaveLength(1);
+  });
+
+  it('leaves a reference with no matching definition literal (no body to inline)', () => {
+    const out = normalizeForeignMarkdown('Dangling[^x] ref.');
+    expect(out).toBe('Dangling[^x] ref.');
+  });
+
+  it('returns the input unchanged when there are no reference footnotes', () => {
+    const md = '# Title\n\nJust text with `inline code` and a [link](/x).';
+    expect(normalizeForeignMarkdown(md)).toBe(md);
+  });
+
+  it('does NOT touch callout surfaces — the canonical parser handles them', () => {
+    const callouts = ':::info\nHi\n:::\n\n> [!warning]\n> Careful';
+    expect(normalizeForeignMarkdown(callouts)).toBe(callouts);
+  });
+
+  it('strips a leading YAML front-matter block (Obsidian/Hugo/git-sync files)', () => {
+    const out = normalizeForeignMarkdown(
+      '---\ntitle: My Page\ntags: [a, b]\n---\n\n# Heading\n\nBody.',
+    );
+    expect(out).toBe('# Heading\n\nBody.');
+    // The front-matter must not leak into the body as a setext heading.
+    expect(out).not.toContain('title: My Page');
+    expect(out).not.toContain('---');
+  });
+
+  it('does not strip a horizontal rule that is not leading front-matter', () => {
+    const md = 'Intro paragraph.\n\n---\n\nAfter the rule.';
+    expect(normalizeForeignMarkdown(md)).toBe(md);
+  });
+
+  it('is linear on a document with thousands of definitions (no quadratic blowup)', () => {
+    // F2(a): the pass-2 rewrite must be O(text), not O(text × defs). Build a
+    // pathological doc (many defs + many plain text lines) and assert it
+    // completes well under a second — a quadratic implementation took ~14s.
+    const N = 4000;
+    const refs = Array.from({ length: N }, (_, i) => `line ${i} plain text`).join('\n');
+    const defs = Array.from({ length: N }, (_, i) => `[^n${i}]: def ${i}`).join('\n');
+    const doc = `start[^n0] and[^n${N - 1}] end\n\n${refs}\n\n${defs}`;
+    const t0 = Date.now();
+    const out = normalizeForeignMarkdown(doc);
+    const elapsed = Date.now() - t0;
+    expect(elapsed).toBeLessThan(2000);
+    // Sanity: the two real references were still inlined.
+    expect(out).toContain('^[def 0]');
+    expect(out).toContain(`^[def ${N - 1}]`);
+  });
+
+  it('is bounded on a long unclosed backtick run (no inline-split ReDoS)', () => {
+    // F2(b): a huge unterminated backtick run must not cause quadratic
+    // backtracking in the inline-code split. Oversized lines skip the split
+    // entirely (left untouched), so this returns promptly.
+    const line = 'x' + '`'.repeat(200000);
+    const doc = `${line}\n\n[^1]: def`;
+    const t0 = Date.now();
+    normalizeForeignMarkdown(doc);
+    expect(Date.now() - t0).toBeLessThan(2000);
+  });
+
+  it('does not crash or slow down on thousands of prefix-chain definition ids', () => {
+    // F7: the rewrite must use a FIXED generic scanner, not an alternation built
+    // from the ids. A `(a|aa|aaa|…)` alternation over prefix-chain ids blows the
+    // V8 regex compiler (FATAL RegExpCompiler Allocation failed — uncatchable,
+    // kills the process). A fixed scanner has no id-dependent compilation cost.
+    const N = 4000;
+    const ids = Array.from({ length: N }, (_, i) => 'a'.repeat(i + 1));
+    const defs = ids.map((id) => `[^${id}]: body ${id.length}`).join('\n');
+    const doc = `ref[^${ids[0]}] and[^${ids[N - 1]}] end\n\n${defs}`;
+    const t0 = Date.now();
+    const out = normalizeForeignMarkdown(doc);
+    expect(Date.now() - t0).toBeLessThan(2000);
+    // Prefix disambiguation is correct: [^a] and [^aaaa...] inline their OWN body.
+    expect(out).toContain('^[body 1]');
+    expect(out).toContain(`^[body ${N}]`);
+  });
+
+  it('strips a CRLF (Windows) front-matter block, not just LF', () => {
+    // F9: the line-anchored regex needs LF after the opening `---`, so a Windows
+    // file (`---\r\n…`) would slip past the strip and leak the front-matter into
+    // the body. normalizeForeignMarkdown normalizes CRLF -> LF first.
+    const out = normalizeForeignMarkdown(
+      '---\r\ntitle: Foo\r\ntags: [a]\r\n---\r\n\r\n# Heading\r\n\r\nBody.',
+    );
+    expect(out).toBe('# Heading\n\nBody.');
+    expect(out).not.toContain('title: Foo');
+    expect(out).not.toContain('---');
+  });
+
+  it('strips front-matter whose value contains a triple-dash (line-anchored)', () => {
+    // F8: the block must close only on a `\n---` LINE, not the first inline
+    // `---`. A value like `title: Q1 --- Q2` must not truncate the front-matter
+    // and leak the rest (author/closing ---) into the body.
+    const out = normalizeForeignMarkdown(
+      '---\ntitle: Q1 --- Q2 results\nauthor: bob\n---\n\nReal body.',
+    );
+    expect(out).toBe('Real body.');
+    expect(out).not.toContain('author: bob');
+    expect(out).not.toContain('Q2 results');
+  });
+});
+
+describe('foreign markdown import acceptance (normalizer + canonical parser)', () => {
+  const FOREIGN = [
+    '# Doc',
+    '',
+    'Body refs [^c] and [^a] and [^b] and again [^a].',
+    '',
+    ':::info',
+    'A legacy callout.',
+    ':::',
+    '',
+    '| h1 | h2 |',
+    '| --- | --- |',
+    '| 1 | 2 |',
+    '',
+    '[^a]: note A',
+    '[^b]: note B',
+    '[^c]: note C',
+    '[^z]: orphan note',
+  ].join('\n');
+
+  it('leaves no literal [^id] or ::: in the imported doc and re-exports canonically', async () => {
+    const normalized = normalizeForeignMarkdown(FOREIGN);
+    const doc = await markdownToProseMirror(normalized);
+    const reexport = convertProseMirrorToMarkdown(doc);
+
+    // No foreign garbage leaks into the document.
+    expect(reexport).not.toMatch(/\[\^/); // no reference footnote refs/defs
+    expect(reexport).not.toContain(':::'); // no legacy callout fences
+
+    // Canonical forms are present.
+    expect(reexport).toContain('^[note C]');
+    expect(reexport).toContain('> [!info]');
+    expect(reexport).toContain('| h1 | h2 |');
+
+    // Footnotes: ordered by first reference (C, A, B), reused [^a] deduped to one,
+    // orphan [^z] dropped (it had no reference after normalization).
+    const list = doc.content.find((n: any) => n.type === 'footnotesList');
+    const bodies = list.content.map(
+      (d: any) => d.content[0].content[0].text,
+    );
+    expect(bodies).toEqual(['note C', 'note A', 'note B']);
+    expect(bodies).not.toContain('orphan note');
+    expect(
+      doc.content.filter((n: any) => n.type === 'footnotesList'),
+    ).toHaveLength(1);
+  });
+});

apps/server/src/integrations/import/utils/foreign-markdown.ts

@@ -0,0 +1,265 @@
+/**
+ * Foreign-markdown normalizer — an input-liberal / output-canonical adapter that
+ * runs at the IMPORT boundary, BEFORE the canonical parser
+ * (`markdownToProseMirror` from `@docmost/prosemirror-markdown`).
+ *
+ * The canonical parser is deliberately STRICT: it only understands Docmost's
+ * canonical markdown surface (Obsidian-style `> [!type]` callouts, Pandoc/Obsidian
+ * inline footnotes `^[body]`, lossless `![alt](src) <!--img {...}-->` images, …).
+ * Import, however, ingests FOREIGN files (GitHub/GFM, Notion, old Docmost
+ * exports). Those use surfaces the canonical parser does not accept, most notably
+ * GitHub-flavoured *reference* footnotes:
+ *
+ *     Text with a note[^1] and another[^long].
+ *
+ *     [^1]: The first definition.
+ *     [^long]: A second one.
+ *
+ * Left untouched, the parser does NOT recognise `[^id]` (it only parses `^[body]`),
+ * so the reference leaks as literal text — and worse, the trailing `[^id]: def`
+ * line is a valid CommonMark *link-reference definition*, so `[^id]` is silently
+ * rendered as a bogus link. This normalizer rewrites reference footnotes into the
+ * canonical inline form so the parser materialises real footnote nodes.
+ *
+ * This is a TEXT pre-pass, NOT a second parser fork: it does not re-implement any
+ * converter logic. Callout surfaces (`:::type` and `> [!type]`) are intentionally
+ * NOT touched here — the canonical parser already accepts BOTH natively (its
+ * `preprocessCallouts` pass), so normalizing them would be redundant and would
+ * only risk degrading the parser's nesting/code-fence-aware handling.
+ */
+
+/** Matches a fenced code block delimiter (``` or ~~~), capturing the marker run. */
+const CODE_FENCE_RE = /^(\s*)(`{3,}|~{3,})/;
+
+/**
+ * Matches a GFM footnote DEFINITION line: `[^id]: body`. The id is any run of
+ * non-`]` characters; the body is the remainder of the line (possibly empty).
+ */
+const FOOTNOTE_DEF_RE = /^\[\^([^\]]+)\]:[ \t]?(.*)$/;
+
+/** True when a line is a code-fence delimiter that toggles fenced-code state. */
+function fenceMarker(line: string): string | null {
+  const m = line.match(CODE_FENCE_RE);
+  return m ? m[2] : null;
+}
+
+/** True when a line is indented (leading space/tab) and not blank — a continuation. */
+function isIndentedContinuation(line: string): boolean {
+  return /^[ \t]+\S/.test(line);
+}
+
+function escapeRegExp(value: string): string {
+  return value.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+}
+
+/**
+ * Backslash-escape any square bracket in a footnote body before it is wrapped in
+ * `^[...]`. The canonical inline-footnote tokenizer scans the body with bracket
+ * balancing and closes on the first UNMATCHED `]`, so an unbalanced bracket in a
+ * foreign definition (e.g. `[^1]: see item ] later`) would otherwise truncate the
+ * footnote and leak the tail as literal text. Escaping every `[`/`]` makes the
+ * body an inert run of characters — the tokenizer then closes only on our own
+ * closing `]`. (A balanced `[link](url)` inside a body still round-trips because
+ * the escaped form renders the literal brackets, which is the safe reading for a
+ * footnote body; the alternative — brittle balance tracking — risks worse.)
+ */
+function escapeFootnoteBody(body: string): string {
+  return body.replace(/[[\]]/g, '\\$&');
+}
+
+/**
+ * Rewrite every `[^id]` reference on a line to its `^[body]` form, but ONLY in the
+ * text OUTSIDE inline-code spans. A `[^id]` inside backticks is literal code
+ * content and must be preserved verbatim (a footnote ref never lives inside code).
+ * We split the line on inline-code spans (paired backtick runs) and rewrite only
+ * the non-code segments.
+ */
+// Above this length a single line is not split into inline-code spans (see
+// below). A genuine markdown line carrying a footnote reference is never tens of
+// KB; the cap only bypasses the inline-code protection for pathological lines.
+const INLINE_SPLIT_MAX_LINE = 8192;
+
+function rewriteRefsOutsideInlineCode(
+  line: string,
+  replace: (text: string) => string,
+): string {
+  // The inline-code split alternation `(`+)(?:(?!\1)[\s\S])*\1` backtracks
+  // quadratically on a long UNCLOSED backtick run (its middle can consume the
+  // rest of the line, then fail to find a closing run and retry from each
+  // position). On an untrusted import this is a request-thread ReDoS. A real
+  // footnote line is short, so for an oversized line we skip the inline-code
+  // protection entirely and leave the line UNTOUCHED (rewriting it wholesale
+  // could corrupt a `[^id]` that legitimately lives inside inline code). This is
+  // a conservative bypass: an over-8KB line simply does not get its reference
+  // footnotes inlined — acceptable for a pathological input.
+  if (line.length > INLINE_SPLIT_MAX_LINE) return line;
+
+  // Alternation: an inline-code span (one or more backticks, then anything up to
+  // the SAME run of backticks) OR a run of non-backtick text. Unterminated
+  // backticks fall through as ordinary text (matched by the second branch on the
+  // leftover), so a stray backtick never swallows the rest of the line.
+  const parts = line.match(/(`+)(?:(?!\1)[\s\S])*\1|[^`]+|`+/g);
+  if (!parts) return line;
+  return parts
+    .map((seg) => (seg.startsWith('`') ? seg : replace(seg)))
+    .join('');
+}
+
+/**
+ * Convert GFM reference footnotes (`[^id]` + `[^id]: def`) into canonical inline
+ * footnotes (`^[def]`).
+ *
+ * - Definitions are collected first (a leading `[^id]: text` line plus any
+ *   immediately-following indented continuation lines, joined with a space) and
+ *   removed from the output.
+ * - Each in-text reference `[^id]` for which a definition was found is replaced by
+ *   `^[def]`. References with no matching definition are left literal (there is no
+ *   body to inline; the parser fails them open the same way).
+ * - Code is respected on both passes: `[^id]` inside a fenced ``` / ~~~ block is
+ *   never rewritten and a `[^id]:` line inside a fence is never a definition; and
+ *   on the rewrite pass a `[^id]` inside an INLINE-code span (backticks) is left
+ *   literal too.
+ * - The inlined body is bracket-escaped so an unbalanced `[`/`]` in a foreign
+ *   definition cannot truncate the resulting `^[...]` footnote.
+ *
+ * Deduplication / reference-ordering / orphan-dropping of the resulting footnotes
+ * is handled downstream by the canonical parser (`assembleFootnotes`); this pass
+ * only changes the surface syntax.
+ */
+function convertReferenceFootnotes(markdown: string): string {
+  const lines = markdown.split('\n');
+
+  // Pass 1: collect definitions and mark their lines for removal.
+  const defs = new Map<string, string>();
+  const dropped = new Array<boolean>(lines.length).fill(false);
+  let inFence = false;
+  let fence = '';
+
+  for (let i = 0; i < lines.length; i++) {
+    const line = lines[i];
+    const marker = fenceMarker(line);
+    if (inFence) {
+      if (marker && marker[0] === fence[0] && marker.length >= fence.length) {
+        inFence = false;
+        fence = '';
+      }
+      continue;
+    }
+    if (marker) {
+      inFence = true;
+      fence = marker;
+      continue;
+    }
+
+    const def = line.match(FOOTNOTE_DEF_RE);
+    if (!def) continue;
+
+    const id = def[1];
+    const body: string[] = [def[2].trim()];
+    dropped[i] = true;
+
+    // Consume immediately-following indented continuation lines (GFM lazy
+    // continuation is not supported by design — keep it simple and predictable).
+    let j = i + 1;
+    while (j < lines.length && isIndentedContinuation(lines[j])) {
+      body.push(lines[j].trim());
+      dropped[j] = true;
+      j++;
+    }
+    i = j - 1;
+
+    // Last definition wins for a duplicated id (matches CommonMark link-ref
+    // semantics closely enough for a foreign-input adapter).
+    defs.set(id, body.filter((s) => s.length > 0).join(' '));
+  }
+
+  if (defs.size === 0) {
+    return markdown;
+  }
+
+  // ONE fixed, generic scanner regex — NOT one built from the definition ids.
+  // It matches ANY `[^id]` shape, and the replacer decides per match via a map
+  // lookup whether that id is a real definition (replace) or not (leave as-is).
+  // This is genuinely O(total text) with no per-document regex compilation.
+  //
+  // Do NOT rebuild this as an alternation over `[...defs.keys()]`: a giant
+  // `(id1|id2|...)` alternation over thousands of ids can blow the V8 regex
+  // compiler's stack — a fatal, UNCATCHABLE "RegExpCompiler Allocation failed"
+  // on prefix-chain ids (`a`, `aa`, `aaa`, ...) that kills the whole process
+  // (worse than the earlier per-def thread-hang). A fixed scanner has no
+  // id-dependent compilation cost and cannot blow up.
+  const refRe = /\[\^([^\]]+)\]/g;
+  const rewriteSegment = (segment: string): string =>
+    segment.replace(refRe, (whole, id: string) => {
+      const body = defs.get(id);
+      // Only real definitions are inlined; an unknown id is left literal (same as
+      // the old per-def loop, which simply never matched it).
+      return body === undefined ? whole : `^[${escapeFootnoteBody(body)}]`;
+    });
+
+  // Pass 2: rewrite in-text references, skipping fenced code and dropped lines.
+  const out: string[] = [];
+  inFence = false;
+  fence = '';
+  for (let i = 0; i < lines.length; i++) {
+    if (dropped[i]) continue;
+    let line = lines[i];
+
+    const marker = fenceMarker(line);
+    if (inFence) {
+      out.push(line);
+      if (marker && marker[0] === fence[0] && marker.length >= fence.length) {
+        inFence = false;
+        fence = '';
+      }
+      continue;
+    }
+    if (marker) {
+      inFence = true;
+      fence = marker;
+      out.push(line);
+      continue;
+    }
+
+    line = rewriteRefsOutsideInlineCode(line, rewriteSegment);
+    out.push(line);
+  }
+
+  return out.join('\n');
+}
+
+/**
+ * Strip a single leading YAML front-matter block (`---\n…\n---`). Foreign files
+ * from Obsidian / Hugo / Jekyll / Notion — and Docmost's OWN git-sync page files
+ * — open with front-matter that the canonical parser does not consume, so
+ * without this it leaks into the body (and `title: Foo` above the closing `---`
+ * renders as a setext `<h2>` that `extractTitleAndRemoveHeading` can hijack as
+ * the page title). It is a no-op for front-matter-free input.
+ *
+ * LINE-ANCHORED (the same shape the canonical parser uses in
+ * prosemirror-markdown/page-file.ts): the block opens only on `---\n` at the
+ * very start and closes only on a `\n---` line. The retired `markdownToHtml`
+ * strip closed on the FIRST `---` ANYWHERE (an unanchored close), so a value
+ * containing a triple-dash (e.g. `title: Q1 --- Q2`) truncated the front-matter
+ * and leaked the rest into the body. An optional leading BOM is tolerated.
+ */
+const YAML_FRONT_MATTER_RE = /^\uFEFF?---\n[\s\S]*?\n---\n?/;
+
+/**
+ * Normalize a foreign markdown string into Docmost's canonical markdown surface
+ * so the strict canonical parser accepts it losslessly: normalize line endings,
+ * strip a leading YAML front-matter block, then rewrite GFM reference footnotes
+ * into inline footnotes. Add further fixture-driven foreign-surface cases here as
+ * they are found.
+ */
+export function normalizeForeignMarkdown(markdown: string): string {
+  if (!markdown) return markdown;
+  // Normalize CRLF -> LF FIRST. The line-anchored front-matter regex requires a
+  // bare `\n` after the opening `---`, and convertReferenceFootnotes splits on
+  // `\n`; a Windows/CRLF foreign file (`---\r\n…`) would otherwise slip past the
+  // front-matter strip and leak into the body. The canonical parser
+  // (page-file.ts parsePageFile) normalizes the same way before its FRONTMATTER_RE.
+  const src = markdown.replace(/\r\n/g, '\n');
+  const withoutFrontMatter = src.replace(YAML_FRONT_MATTER_RE, '').trimStart();
+  return convertReferenceFootnotes(withoutFrontMatter);
+}

apps/server/test/stubs/tiptap-react.js

@@ -0,0 +1,23 @@
+// Jest stub for @tiptap/react.
+//
+// The server export/import code paths transitively import editor-ext, whose node
+// extensions import from `@tiptap/react`. The real module re-exports all of
+// `@tiptap/core` (headless, safe under node) AND adds React view helpers
+// (`ReactNodeViewRenderer`, …) that eagerly pull in react-dom — which throws
+// `navigator is not defined` under jest's node environment.
+//
+// So this stub DELEGATES to the real `@tiptap/core` (keeping `mergeAttributes`,
+// `Node`, `Mark`, `nodeInputRule`, … working — they are used by
+// `jsonToHtml`/`htmlToJson` on the server) and overrides ONLY the React view
+// helpers with no-ops. Those helpers are referenced solely inside `addNodeView()`
+// — code that runs only in a live browser editor, never on the server; if any
+// were actually invoked here it would (correctly) surface as a test failure.
+const core = require('@tiptap/core');
+
+module.exports = {
+  ...core,
+  ReactNodeViewRenderer: () => () => ({}),
+  NodeViewWrapper: () => null,
+  NodeViewContent: () => null,
+  ReactRenderer: class {},
+};

docs/dev-stand.md

@@ -131,5 +131,14 @@ const { Client } = require("pg");
 7. **Migrations don't auto-run in dev** — run `migration:latest` after every pull
    or branch switch.
 
+8. **Automation (Playwright): type into the BODY editor, not the title.** A page has
+   two `.ProseMirror` editors — `[aria-label='Page title']` (non-collab) and
+   `[aria-label='Page content']` (the collab body). `document.querySelector('.ProseMirror')`
+   returns the TITLE editor, so typing there never changes body content and `mod+S`
+   versions nothing. Target `[aria-label='Page content']`, confirm it's collab-bound
+   (`el.editor.extensionManager.extensions.some(e=>e.name==='collaboration')`), and
+   wait ~10-12s for the store debounce before asserting `pages.content` changed. Full
+   testing methodology + traps: **[how-to-test.md](how-to-test.md)**.
+
 See also the **Commands** and **Architecture → Two server processes** sections in
 [`AGENTS.md`](../AGENTS.md).

docs/how-to-test.md

@@ -0,0 +1,108 @@
+# How to test the application (browser E2E + out-of-band)
+
+How to actually verify a feature end-to-end against a running stand — driving the
+**real app in a browser** and confirming results **out-of-band** in the DB/git, not
+through the same API you're supposed to be testing. Written from real false-positives
+that wasted hours (see **Traps** — read them before you write a test).
+
+Prereq: a running stand — see **[dev-stand.md](dev-stand.md)**. Automation uses
+Playwright (`pip install playwright && python -m playwright install chromium`).
+
+## Principles
+
+1. **Drive the behaviour under test through the browser.** The stand exists so you
+   exercise the real UI + realtime-collab + server path. Using `POST /api/pages/*` to
+   perform the action you're validating tests the API, not the app — an e2e suite can
+   do that. API calls are fine ONLY for one-time setup/fixtures, never for the
+   interaction you're asserting on.
+2. **Evidence before claim.** Nothing "passes" without an artifact: a DB row, a git
+   diff, a screenshot looked at as an image. If you can't show it, you didn't verify it.
+3. **Verify out-of-band.** Judge results from a source independent of the UI: `psql`
+   against the DB, a fresh `git clone` of a synced repo, a hard reload. Optimistic UI
+   lies about persistence.
+4. **Disconfirm by default.** For each feature, actively try to prove it's broken
+   before concluding it works. Reload after every create/edit/save.
+5. **Recon actuatability FIRST.** Before building editor tests, confirm the
+   interaction even works in your harness (does a typed edit reach the DB?). Skipping
+   this is how you ship a pile of tests that all silently exercised the wrong thing.
+
+## The editor: two ProseMirror instances (READ THIS)
+
+A page has **two** `.ProseMirror` editors:
+
+| index | selector | role | collab? |
+|---|---|---|---|
+| 0 | `[aria-label='Page title']` | title field | **NO** (16 exts, no `collaboration`) |
+| 1 | `[aria-label='Page content']` | body | **YES** (95 exts, has `collaboration`) |
+
+`document.querySelector('.ProseMirror')` returns the **title** editor (first match).
+Type there and you edit the title only — body page content never changes, so `mod+S`
+"versions" unchanged content and every content test silently no-ops.
+
+**Always target the body editor** and confirm it's collab-bound before typing:
+
+```js
+const el = document.querySelector("[aria-label='Page content']");
+el.editor.extensionManager.extensions.some(e => e.name === 'collaboration'); // must be true
+```
+
+Body edits emit ~20 `/collab` websocket frames while typing and land in
+`pages.content` after the **hocuspocus store debounce (~10s)** — so **wait ~12s**
+before asserting persistence (checking at 6–8s is a false negative). `mod+S` (the
+`save-version` stateless message) flushes immediately, so a version created right
+after a settled body edit holds the typed text.
+
+## A known-good browser flow
+
+```
+1. goto /s/<space-slug>            # the "Create page" button lives in the space sidebar, not /home
+2. click button[aria-label='Create page']   # fully UI-driven page creation
+3. type into [aria-label='Page title']       # optional title
+4. click [aria-label='Page content'] → type body text
+5. wait ~12s (store debounce)
+6. assert pages.content changed (psql)       # out-of-band
+7. mod+S / menu Save → assert page_history row (psql)
+8. reload / fresh context → re-assert (persistence round-trip)
+```
+
+Auth: log in ONCE, save `storage_state.json`, reuse it across pages/agents (re-login
+per run trips shared rate-limits). Cookie-based session authorizes both REST and the
+collab websocket.
+
+## Judging out-of-band
+
+```bash
+# page content / history
+docker exec <db> psql -U docmost -d docmost -tAc \
+  "select coalesce(kind,'null'), content::text from page_history where page_id='<id>' order by created_at;"
+# git-sync round-trip: clone the space repo and diff against what you pushed
+git clone http://<user>:<pass>@127.0.0.1:3000/git/<spaceId>.git /tmp/x
+```
+
+`page_history.content` is full JSON — parse it, don't truncate the snippet, or a
+marker check misses. For sync/async features (autosave, git-sync, idle-flush) use an
+active probe: write a unique marker, wait past the debounce/poll window, re-read
+out-of-band, ≥2 iterations — never conclude "broken" from a single snapshot.
+
+## Traps (each of these produced a false result in a real run)
+
+- **Wrong editor.** Typed into `.ProseMirror` (= title). Edits never touched body
+  content. → target `[aria-label='Page content']`.
+- **Checked persistence too early.** Store debounce ~10s; a 6–8s check reads stale.
+- **Truncated the DB snapshot** below where the test marker sits → false "content
+  missing".
+- **API-seeded the content under test**, then "verified" the feature — that validated
+  the API, not the app.
+- **Reused a fixed marker on a non-rebooted stand** → title/row collisions inflate
+  counts (`count==2`). Use a unique per-run marker (timestamp).
+- **Idle/async read once** and called it "permanently broken" — it was mid-debounce.
+- **Concluded env-limitation without a cross-build control.** If unsure whether a
+  failure is your harness or the product, run the SAME harness against a known-good
+  build; a divergence localizes it.
+
+## Scope note
+
+Some paths genuinely need a human in a real browser (rich drag-drop, native file
+pickers, clipboard, and anything the harness can't actuate). Label those UNTESTED in
+the report — "handled gracefully" is not "works". Keep four states distinct:
+verified-working, defect, untested, env-limitation.

package.json

@@ -96,7 +96,8 @@
   "pnpm": {
     "patchedDependencies": {
       "scimmy@1.3.5": "patches/scimmy@1.3.5.patch",
-      "yjs@13.6.30": "patches/yjs@13.6.30.patch"
+      "yjs@13.6.30": "patches/yjs@13.6.30.patch",
+      "ai@6.0.134": "patches/ai@6.0.134.patch"
     },
     "overrides": {
       "prosemirror-changeset": "2.4.0",

packages/prosemirror-markdown/test/fixtures/counterexamples/columns-column-width-percent.json

@@ -0,0 +1,16 @@
+{
+  "_bug": "BUG #351: a `column` whose `width` is a percentage string (e.g. \"50%\") is NOT byte-stable across export->import->export (violates P2). The `column` schema's parseHTML does `parseFloat(getAttribute('data-width'))`, which silently drops the '%' unit and returns the NUMBER 50. So the first export emits data-width=\"50%\" but the re-import stores width=50, and the second export emits data-width=\"50\": md2 !== md1, a permanent GS-EDIT-REVERT churn (every git-sync pull rewrites the column width). The editor authors column widths as percentages, so this is a real data/round-trip defect. Fix belongs in src/lib/docmost-schema.ts column.width parseHTML (preserve the unit / keep the string), which is OUT OF SCOPE for this test-only PR and must be a separate, maintainer-approved change. This flat generator therefore keeps `column.width` frozen (never generates a non-default width).",
+  "doc": {
+    "type": "doc",
+    "content": [
+      {
+        "type": "columns",
+        "attrs": { "layout": "two_equal", "widthMode": "normal" },
+        "content": [
+          { "type": "column", "attrs": { "width": "50%" }, "content": [{ "type": "paragraph", "content": [{ "type": "text", "text": "L" }] }] },
+          { "type": "column", "attrs": { "width": "50%" }, "content": [{ "type": "paragraph", "content": [{ "type": "text", "text": "R" }] }] }
+        ]
+      }
+    ]
+  }
+}

packages/prosemirror-markdown/test/fixtures/counterexamples/ordered-list-start.json

@@ -0,0 +1,19 @@
+{
+  "doc": {
+    "type": "doc",
+    "content": [
+      {
+        "type": "orderedList",
+        "attrs": { "type": null, "start": 5 },
+        "content": [
+          {
+            "type": "listItem",
+            "content": [
+              { "type": "paragraph", "content": [{ "type": "text", "text": "alpha" }] }
+            ]
+          }
+        ]
+      }
+    ]
+  }
+}

packages/prosemirror-markdown/test/generative/attr-arbitraries.ts

@@ -0,0 +1,325 @@
+/**
+ * Schema-DERIVED attribute-state fast-check arbitraries (#351, PR 1).
+ *
+ * This GENERALIZES the #350 stability-matrix helper (roundtrip-stability.helper.ts)
+ * to fast-check. Where that helper sweeps a HAND-WRITTEN 2-state matrix for one
+ * node spec, this module reads the attribute list straight from
+ * `schema.nodes[type].spec.attrs` (never a hand list) and, per attribute,
+ * generates over the FOUR states the issue calls for:
+ *
+ *   - `absent`      : the attribute is OMITTED entirely (the empty-string-vs-
+ *                     absent churn class the #350 fix targets).
+ *   - `default`     : the schema default value, authored explicitly.
+ *   - `nonDefault`  : a representative legal non-default value.
+ *   - `degenerate`  : `""` for strings, `0`/negative for numbers, the flipped
+ *                     value for booleans.
+ *
+ * ── Why a per-attribute override table ──────────────────────────────────────
+ * Everything that CAN be derived generically from the default's runtime type is
+ * (booleans flip; the degenerate value follows the runtime type). But two facts
+ * force a small, DOCUMENTED override table:
+ *
+ *  1. CONSTRAINED domains the schema does not encode. `image.align ∈
+ *     {left,center,right}`, `heading.level ∈ 1..6`, `callout.type ∈
+ *     {info,success,warning,danger}`, `columns.layout`, table-cell `align`,
+ *     `status.color`, `orderedList.start ≥ 1`, etc. A generic "default + 1"
+ *     would emit an ILLEGAL value, so these get an explicit legal domain.
+ *  2. ROUND-TRIP-safety, established EMPIRICALLY by probing the live converter
+ *     (the classification captured in flat-roundtrip.property.test.ts). A frozen
+ *     attribute falls into ONE of TWO explicitly-distinguished classes — never a
+ *     silent "it just doesn't round-trip":
+ *
+ *       (a) ACCEPTED LIMITATION — the attribute has NO markdown representation,
+ *           so the loss is inherent to targeting markdown, not a converter
+ *           defect. These: `paragraph`/`heading` `indent`, `callout.icon`,
+ *           `orderedList.type` (a/A/i markers), table `colwidth` /
+ *           `backgroundColor(Name)` (dropped by the raw-<table> fallback). Each is
+ *           tagged `// ACCEPTED:` inline. Freezing them is correct — there is
+ *           nothing to preserve in the target format.
+ *
+ *       (b) PINNED BUG — the attribute IS representable in markdown but the
+ *           converter drops it anyway (a real defect). These are NOT silently
+ *           frozen: each is captured as a LOUD `it.fails` counterexample in
+ *           test/fixtures/counterexamples/ + counterexamples.test.ts, and the
+ *           freeze here only keeps the P1/P2 union green until a MAINTAINER rules
+ *           on accept-vs-fix (the epic guardrail reserves that call). These:
+ *           `column.width` (parseFloat drops `%`), `orderedList.start` (non-1
+ *           start renders as `1.`). Tagged `// PINNED-BUG:` inline.
+ *
+ *       (c) DEFERRED-BUG — representable AND round-trips, frozen only because the
+ *           flat generator can't yet build a valid instance. Table
+ *           `colspan`/`rowspan` round-trip via the raw-<table> fallback, but a
+ *           geometrically-valid spanned table is PR-2 structural work; the flat
+ *           generator hardcodes span = 1. Tagged `// DEFERRED-BUG:` inline so a
+ *           maintainer does not read them as an inherent limitation.
+ *       - Several non-null-default attrs are MATERIALIZED on import but are not
+ *         in canonicalize's KNOWN_DEFAULTS (`callout.type`, `status.color`,
+ *         table `colspan`/`rowspan`, `columns.layout`/`widthMode`,
+ *         `embed.width`/`height`, `heading.level`, `taskItem.checked`,
+ *         `details.open`, `subpages.recursive`, `orderedList.start`). If left
+ *         `absent` they re-materialize as a non-canonical default and diverge
+ *         under P1. We mark them `always` so they are authored explicitly.
+ *       - The documented numeric→string coercion set (`width height size
+ *         aspectRatio`) is generated as STRINGS for the media family (a stored
+ *         number re-parses as a string), EXCEPT `embed.width/height` which the
+ *         embed schema keeps numeric — handled per-attr.
+ *
+ * Both PINNED-BUG attrs (`column.width` P2 churn, `orderedList.start` P1 loss)
+ * are captured as committed `it.fails` counterexamples — NOT hidden here.
+ */
+import fc from 'fast-check';
+import { getSchema } from '@tiptap/core';
+import { docmostExtensions } from '../../src/lib/index.js';
+import { phraseArb, letterPhraseArb, urlArb } from './text-arbitraries.js';
+
+/** The exact ProseMirror schema the converter targets. */
+export const schema = getSchema(docmostExtensions as any);
+
+/** Sentinel: this attribute is OMITTED (the `absent` state). */
+export const ABSENT = Symbol('ABSENT');
+
+/** The documented numeric→string coercion set (issue + roundtrip-stability.helper). */
+export const NUMERIC_STRING_ATTRS = ['width', 'height', 'size', 'aspectRatio'];
+
+/** Read the schema default for every attribute of a node type. */
+export function schemaAttrDefaults(type: string): Record<string, unknown> {
+  const specAttrs = (schema.nodes[type]?.spec?.attrs ?? {}) as Record<
+    string,
+    { default: unknown }
+  >;
+  const out: Record<string, unknown> = {};
+  for (const [k, v] of Object.entries(specAttrs)) out[k] = v.default;
+  return out;
+}
+
+/** Attribute names for a node type, straight from the schema (never hand-listed). */
+export function schemaAttrNames(type: string): string[] {
+  return Object.keys((schema.nodes[type]?.spec?.attrs ?? {}) as object);
+}
+
+/**
+ * Per-attribute policy. Everything unlisted falls back to a generic policy:
+ *   - a BOOLEAN default is fuzzable (its non-default is the flipped value);
+ *   - any other default is `frozen` (only `absent`/`default` are generated) so
+ *     we never invent an unverified non-default that might not round-trip.
+ * Listed attrs override this with a legal `arb` domain and/or flags.
+ */
+interface AttrPolicy {
+  /** Arbitrary for the `nonDefault` state's value. */
+  arb?: fc.Arbitrary<unknown>;
+  /** Value for the `degenerate` state (fuzz mode only). Omit to skip degenerate. */
+  degen?: unknown;
+  /** Never emit `absent` — the attr must be authored (materialized default class). */
+  always?: boolean;
+  /** Never emit the schema default value (required-ish attrs like `src`). Implies always. */
+  noDefault?: boolean;
+  /** Never emit non-default/degenerate — attr has no md representation or churns. */
+  frozen?: boolean;
+}
+
+const num = (...xs: number[]) => fc.constantFrom(...xs);
+const str = (...xs: string[]) => fc.constantFrom(...xs);
+const widthStr = str('120', '320', '640');
+
+// The documented override table, keyed `type.attr`. Every entry is grounded in
+// the empirical converter probe (see flat-roundtrip.property.test.ts header).
+const OVERRIDES: Record<string, AttrPolicy> = {
+  // ── block text containers ────────────────────────────────────────────────
+  // 'left' is the IMPLICIT default alignment: the converter drops it on export
+  // (empirically confirmed), so it never round-trips. Only center/right/justify
+  // carry through the `<!--attrs {textAlign}-->` comment.
+  'paragraph.textAlign': { arb: str('center', 'right', 'justify') },
+  'paragraph.indent': { frozen: true }, // ACCEPTED: no md representation
+  'heading.level': { always: true, arb: num(2, 3, 4, 5, 6) },
+  'heading.textAlign': { arb: str('center', 'right', 'justify') },
+  'heading.indent': { frozen: true }, // ACCEPTED: no md representation
+  // ── lists ────────────────────────────────────────────────────────────────
+  // PINNED-BUG: markdown CAN express a non-1 start ("5."), but the converter
+  // renders "1." and drops it -> P1 loss. See counterexamples.test.ts
+  // (ordered-list-start.json). Frozen only until the maintainer rules accept-vs-fix.
+  'orderedList.start': { always: true, frozen: true },
+  'orderedList.type': { frozen: true }, // ACCEPTED: a/A/i markers not expressible in GFM
+  'taskItem.checked': { always: true, arb: fc.constant(true) }, // boolean, default false
+  // ── codeBlock ────────────────────────────────────────────────────────────
+  'codeBlock.language': { arb: str('js', 'ts', 'python', 'go', 'rust', 'bash') },
+  // ── image / media (numeric→string width family) ──────────────────────────
+  'image.src': { noDefault: true, arb: urlArb, degen: '' },
+  'image.align': { arb: str('left', 'right') },
+  'image.alt': { arb: letterPhraseArb, degen: '' },
+  'image.title': { arb: letterPhraseArb },
+  'image.width': { arb: widthStr, degen: '' },
+  'image.height': { arb: widthStr, degen: '' },
+  'video.src': { noDefault: true, arb: urlArb, degen: '' },
+  'video.alt': { arb: letterPhraseArb },
+  'video.width': { arb: widthStr },
+  'video.height': { arb: widthStr },
+  'audio.src': { noDefault: true, arb: urlArb, degen: '' },
+  'youtube.src': { noDefault: true, arb: urlArb },
+  'pdf.src': { noDefault: true, arb: urlArb },
+  'pdf.name': { arb: phraseArb },
+  'drawio.src': { noDefault: true, arb: urlArb },
+  'excalidraw.src': { noDefault: true, arb: urlArb },
+  'attachment.url': { noDefault: true, arb: urlArb },
+  'attachment.name': { arb: phraseArb },
+  // ── callout / status ─────────────────────────────────────────────────────
+  'callout.type': { always: true, arb: str('success', 'warning', 'danger') },
+  'callout.icon': { frozen: true }, // ACCEPTED: no md representation (dropped on export)
+  'status.text': { noDefault: true, arb: phraseArb, degen: '' },
+  'status.color': { always: true, arb: str('green', 'orange', 'red', 'blue', 'yellow', 'purple') },
+  // ── table cells ────────────────────────────────────────────────────────────
+  // DEFERRED-BUG (not ACCEPTED): colspan/rowspan ARE representable and round-trip
+  // — a spanned cell makes the converter emit the whole table as a raw <table>
+  // with colspan/rowspan attrs (markdown-converter.ts tableToHtml), which the
+  // tiptap parser reads back. They are frozen only because generating a
+  // geometrically-valid spanned table is deferred STRUCTURAL work (the flat
+  // generator hardcodes colspan/rowspan = 1), NOT a markdown limitation.
+  'tableCell.colspan': { always: true, frozen: true },
+  'tableCell.rowspan': { always: true, frozen: true },
+  // ACCEPTED: colwidth / backgroundColor(Name) have no representation — the
+  // raw-<table> fallback (tableToHtml) drops them, so there is nothing to preserve.
+  'tableCell.colwidth': { frozen: true },
+  'tableCell.backgroundColor': { frozen: true },
+  'tableCell.backgroundColorName': { frozen: true },
+  'tableCell.align': { arb: str('left', 'center', 'right') },
+  'tableHeader.colspan': { always: true, frozen: true }, // DEFERRED-BUG (see tableCell.colspan)
+  'tableHeader.rowspan': { always: true, frozen: true }, // DEFERRED-BUG (see tableCell.rowspan)
+  'tableHeader.colwidth': { frozen: true }, // ACCEPTED: no representation
+  'tableHeader.backgroundColor': { frozen: true }, // ACCEPTED: no representation
+  'tableHeader.backgroundColorName': { frozen: true }, // ACCEPTED: no representation
+  'tableHeader.align': { arb: str('left', 'center', 'right') },
+  // ── details ──────────────────────────────────────────────────────────────
+  'details.open': { always: true, arb: fc.constant(true) }, // boolean, default false
+  // ── columns ──────────────────────────────────────────────────────────────
+  'columns.layout': { always: true, arb: str('three_equal', 'left_sidebar', 'right_sidebar') },
+  // widthMode round-trips via the `data-width-mode` attribute (verified P1+P2),
+  // so it is fuzzed, not frozen.
+  'columns.widthMode': { always: true, arb: str('custom') },
+  // PINNED-BUG: parseFloat import drops the `%` unit -> P2 churn. See
+  // counterexamples.test.ts (columns-column-width-percent.json).
+  'column.width': { frozen: true },
+  // ── embed (schema keeps width/height NUMERIC, not string-coerced) ─────────
+  'embed.src': { noDefault: true, arb: urlArb, degen: '' },
+  'embed.provider': { noDefault: true, arb: str('iframe', 'youtube', 'vimeo') },
+  'embed.width': { always: true, frozen: true },
+  'embed.height': { always: true, frozen: true },
+  // ── subpages / math / htmlEmbed ──────────────────────────────────────────
+  'subpages.recursive': { always: true, arb: fc.constant(true) }, // boolean, default false
+  'mathBlock.text': { noDefault: true, arb: str('x^2', 'a < b', '\\frac{1}{2}'), degen: '' },
+  'mathInline.text': { noDefault: true, arb: str('x^2', 'a < b', '\\frac{1}{2}'), degen: '' },
+  'htmlEmbed.source': { noDefault: true, arb: str('<b>hi</b>', '<i>x</i>', '<span>y</span>'), degen: '' },
+  'htmlEmbed.height': { arb: num(200, 300, 400) },
+  // ── footnotes / transclusion / pageEmbed / mention ───────────────────────
+  'footnoteDefinition.id': { noDefault: true, arb: str('fn1', 'fn2', 'note') },
+  'footnoteReference.id': { noDefault: true, arb: str('fn1', 'fn2', 'note') },
+  'pageEmbed.sourcePageId': { noDefault: true, arb: fc.uuid() },
+  'transclusionSource.id': { noDefault: true, arb: str('src1', 'src2') },
+  'transclusionReference.sourcePageId': { noDefault: true, arb: fc.uuid() },
+  'transclusionReference.transclusionId': { noDefault: true, arb: str('tr1', 'tr2') },
+  'mention.id': { noDefault: true, arb: fc.uuid() },
+  'mention.label': { noDefault: true, arb: phraseArb },
+  'mention.entityType': { noDefault: true, arb: str('user') },
+  'mention.entityId': { noDefault: true, arb: fc.uuid() },
+};
+
+/** Resolve the effective policy for one attribute (override merged over generic). */
+function policyFor(type: string, attr: string, def: unknown): AttrPolicy {
+  const override = OVERRIDES[`${type}.${attr}`];
+  if (override) return override;
+  // Generic: booleans are fuzzable via their flipped value; everything else is
+  // frozen (only absent/default) so no unverified non-default is invented.
+  if (typeof def === 'boolean') return { arb: fc.constant(!def) };
+  return { frozen: true };
+}
+
+/**
+ * Whether an attribute is actually exercised at a NON-DEFAULT value (i.e. its
+ * policy has an `arb`, which the generic fallback does not). Used by the
+ * attribute-coverage snapshot test to make the generic-frozen space VISIBLE: any
+ * string/number attr not in OVERRIDES is silently only tested at absent/default,
+ * so the snapshot pins exactly which attrs are NOT value-fuzzed and forces a
+ * reviewer to look when a new attr lands in that invisible bucket.
+ */
+export function attrIsValueFuzzed(type: string, attr: string): boolean {
+  const def = schemaAttrDefaults(type)[attr];
+  return !!policyFor(type, attr, def).arb;
+}
+
+/** Every node `type.attr` in the schema (excluding the auto `id`), sorted. */
+export function allSchemaAttrKeys(): string[] {
+  const keys: string[] = [];
+  for (const type of Object.keys(schema.nodes)) {
+    for (const attr of schemaAttrNames(type)) {
+      if (attr === 'id') continue;
+      keys.push(`${type}.${attr}`);
+    }
+  }
+  return keys.sort();
+}
+
+/**
+ * Every MARK attribute in the schema, keyed `mark:<name>.<attr>`, sorted. Marks
+ * are not driven by the node OVERRIDES table (they are fuzzed by the text
+ * generator, text-arbitraries.ts), so their value-fuzz coverage is tracked with a
+ * separate snapshot (see flat-roundtrip.property.test.ts) — without this the
+ * "no invisible coverage hole" guarantee would hold for node attrs only, letting a
+ * new mark attr slip through unfuzzed and unallowlisted.
+ */
+export function allSchemaMarkAttrKeys(): string[] {
+  const keys: string[] = [];
+  for (const [name, mark] of Object.entries(schema.marks)) {
+    const attrs = (mark.spec?.attrs ?? {}) as Record<string, unknown>;
+    for (const attr of Object.keys(attrs)) keys.push(`mark:${name}.${attr}`);
+  }
+  return keys.sort();
+}
+
+export type AttrMode = 'p1' | 'fuzz';
+
+/**
+ * Build an arbitrary for ONE attribute's value (or the ABSENT sentinel) across
+ * the states legal for `mode`:
+ *   - p1   : absent / default / nonDefault (the round-trip-safe space).
+ *   - fuzz : the above PLUS degenerate (P2 tolerates the one-time
+ *            normalization; P3 only needs totality).
+ */
+export function attrValueArb(
+  type: string,
+  attr: string,
+  mode: AttrMode,
+): fc.Arbitrary<unknown | typeof ABSENT> {
+  const def = schemaAttrDefaults(type)[attr];
+  const p = policyFor(type, attr, def);
+
+  const states: fc.Arbitrary<unknown | typeof ABSENT>[] = [];
+  if (!p.always && !p.noDefault) states.push(fc.constant(ABSENT));
+  if (!p.noDefault) states.push(fc.constant(def));
+  if (!p.frozen && p.arb) states.push(p.arb);
+  if (mode === 'fuzz' && !p.frozen && p.degen !== undefined) {
+    states.push(fc.constant(p.degen));
+  }
+  if (states.length === 0) states.push(fc.constant(def));
+  return fc.oneof(...states);
+}
+
+/**
+ * Build an arbitrary for a node's full `attrs` object over all schema attrs.
+ * `base` pins caller-required attrs (e.g. a concrete `src`) verbatim; any attr
+ * present in `base` is NOT re-generated. Omitted (ABSENT) attrs are dropped.
+ */
+export function nodeAttrsArb(
+  type: string,
+  mode: AttrMode,
+  base: Record<string, unknown> = {},
+): fc.Arbitrary<Record<string, unknown>> {
+  const names = schemaAttrNames(type).filter((n) => !(n in base) && n !== 'id');
+  if (names.length === 0) return fc.constant({ ...base });
+  return fc
+    .tuple(...names.map((n) => attrValueArb(type, n, mode)))
+    .map((vals) => {
+      const attrs: Record<string, unknown> = { ...base };
+      names.forEach((n, i) => {
+        if (vals[i] !== ABSENT) attrs[n] = vals[i];
+      });
+      return attrs;
+    });
+}

packages/prosemirror-markdown/test/generative/counterexamples.test.ts

@@ -0,0 +1,74 @@
+import { describe, expect, it } from 'vitest';
+import { readFileSync } from 'node:fs';
+import { fileURLToPath } from 'node:url';
+import path from 'node:path';
+import { convertProseMirrorToMarkdown } from '../../src/lib/markdown-converter.js';
+import { markdownToProseMirror } from '../../src/lib/markdown-to-prosemirror.js';
+import { docsCanonicallyEqual } from '../../src/lib/canonicalize.js';
+
+// ---------------------------------------------------------------------------
+// #351 committed counterexamples — REAL round-trip bugs surfaced by the flat
+// generative probing (attribute level). Each is pinned here as an `it.fails`
+// (vitest passes ONLY WHILE the assertion still fails), so that the day the
+// underlying src/ bug is fixed, the `it.fails` starts PASSING and vitest turns
+// this test RED — forcing us to delete the counterexample and (per the epic
+// guardrail) tighten the generator. A bare `it.fails` would ship silent
+// corruption, so every case below carries a loud `// BUG #351:` explanation.
+//
+// These bugs are NOT worked around by weakening any property: the offending
+// attribute is kept OUT of the P1/P2 generators (documented in
+// attr-arbitraries.ts), and the exact failing document lives here as the
+// regression pin. FIXING the bug is a separate, maintainer-approved src/ change.
+// ---------------------------------------------------------------------------
+
+const here = path.dirname(fileURLToPath(import.meta.url));
+const fixtureDir = path.resolve(here, '../fixtures/counterexamples');
+
+function loadDoc(file: string): any {
+  return JSON.parse(readFileSync(path.join(fixtureDir, file), 'utf8')).doc;
+}
+
+describe('#351 counterexamples (known round-trip bugs, pinned as it.fails)', () => {
+  // BUG #351: a `column` with a PERCENTAGE width ("50%") is not byte-stable.
+  // The column schema parses `data-width` with parseFloat, dropping the '%':
+  //   md1 = '...data-width="50%"...'   (first export)
+  //   re-import stores width = 50 (number)
+  //   md2 = '...data-width="50"...'    (second export)  => md2 !== md1
+  // A permanent GS-EDIT-REVERT churn on every git-sync pull. The editor stores
+  // column widths as percentages, so this is a genuine defect. The fix is in
+  // src/lib/docmost-schema.ts (column.width parseHTML must preserve the unit)
+  // and is out of scope for this test-only PR.
+  it.fails('column percentage width is byte-stable (P2)', async () => {
+    const doc = loadDoc('columns-column-width-percent.json');
+    const md1 = convertProseMirrorToMarkdown(doc);
+    const doc2 = await markdownToProseMirror(md1);
+    const md2 = convertProseMirrorToMarkdown(doc2);
+    // This assertion currently FAILS (md2 drops the '%'), which is exactly what
+    // `it.fails` expects. When the schema is fixed, it will PASS and flip this
+    // test red — our cue to remove the pin.
+    expect(md2).toBe(md1);
+  });
+
+  // BUG #351: an `orderedList` with a non-1 `start` loses its start number.
+  // CommonMark CAN express this ("5." starts the list at 5), but the converter
+  // always emits "1." and ignores `attrs.start` (markdown-converter.ts renders
+  // `${index + 1}.`; the <ol> HTML path also omits `start`):
+  //   doc.start = 5   ->   md1 = "1. alpha"   (start dropped on export)
+  //   re-import stores start = 1   =>   docsCanonicallyEqual(rt, doc) === false
+  // This is a P1 (semantic round-trip) loss of the SAME class as column.width:
+  // representable in markdown, silently dropped by the converter. It is pinned
+  // here as the LOUD counterexample rather than being masked as an "accepted
+  // normalization" in the generator — per the epic guardrail, deciding
+  // accept-vs-fix for a markdown-representable loss is a MAINTAINER call, so this
+  // stays a visible known-bug until the maintainer rules on it. The fix would be
+  // in src/lib/markdown-converter.ts (emit the start number on the first item)
+  // and is out of scope for this test-only PR.
+  it.fails('ordered list start number is preserved (P1)', async () => {
+    const doc = loadDoc('ordered-list-start.json');
+    const md1 = convertProseMirrorToMarkdown(doc);
+    const doc2 = await markdownToProseMirror(md1);
+    // Currently FAILS: doc2.start === 1 while doc.start === 5. When the converter
+    // preserves `start`, this PASSES and flips the test red — remove the pin then.
+    expect(docsCanonicallyEqual(doc2, doc)).toBe(true);
+  });
+});

packages/prosemirror-markdown/test/generative/flat-roundtrip.property.test.ts

@@ -0,0 +1,284 @@
+import { describe, expect, it, vi } from 'vitest';
+import fc from 'fast-check';
+// Real converter, imported the same way the sibling property test does.
+import { convertProseMirrorToMarkdown } from '../../src/lib/markdown-converter.js';
+// Importing markdownToProseMirror mutates the global DOM via jsdom at module
+// load (expected, required for @tiptap/html's generateJSON under Node).
+import { markdownToProseMirror } from '../../src/lib/markdown-to-prosemirror.js';
+import { docsCanonicallyEqual, canonicalizeContent } from '../../src/lib/index.js';
+import { firstDivergence } from '../roundtrip-helpers.js';
+import {
+  schema,
+  allSchemaAttrKeys,
+  allSchemaMarkAttrKeys,
+  attrIsValueFuzzed,
+} from './attr-arbitraries.js';
+import {
+  buildGenerators,
+  coveredTypes,
+  KNOWN_UNCOVERED,
+} from './node-generators.js';
+
+// ── Attribute-value coverage allowlist ──────────────────────────────────────
+// The node/mark completeness contract guarantees every TYPE is generated, but
+// NOT that every attribute is exercised at a NON-DEFAULT value. An attribute
+// with no `arb` in attr-arbitraries.ts is only ever tested at absent/default —
+// an INVISIBLE coverage hole (the reviewer's concern). This allowlist makes that
+// hole EXPLICIT: it is the exact set of attrs deliberately not value-fuzzed, so
+// a NEW attribute (or a newly-frozen one) that lands in this bucket flips the
+// snapshot test red and forces a reviewer to classify it. Each belongs to one of:
+//   - internal/opaque ids & placeholders (attachmentId, slugId, placeholder,
+//     creatorId, anchorId) — no meaningful non-default to assert;
+//   - dimensions/among the media family with no standalone md form here
+//     (aspectRatio, size, caption, drawio/excalidraw/pdf/video/youtube w/h/align)
+//     — round-trip candidates deferred to a later PR, not silently dropped;
+//   - ACCEPTED limitations with no md representation (indent, callout.icon,
+//     orderedList.type, table spans/bg/colwidth);
+//   - PINNED bugs (column.width, orderedList.start) tracked in
+//     counterexamples.test.ts.
+const ATTR_VALUE_FUZZ_ALLOWLIST = new Set<string>([
+  'attachment.attachmentId', 'attachment.mime', 'attachment.placeholder', 'attachment.size',
+  'audio.attachmentId', 'audio.placeholder', 'audio.size',
+  'callout.icon', 'column.width',
+  'drawio.align', 'drawio.alt', 'drawio.aspectRatio', 'drawio.attachmentId',
+  'drawio.height', 'drawio.size', 'drawio.title', 'drawio.width',
+  'embed.align', 'embed.height', 'embed.width',
+  'excalidraw.align', 'excalidraw.alt', 'excalidraw.aspectRatio', 'excalidraw.attachmentId',
+  'excalidraw.height', 'excalidraw.size', 'excalidraw.title', 'excalidraw.width',
+  'heading.indent',
+  'image.aspectRatio', 'image.attachmentId', 'image.caption', 'image.placeholder', 'image.size',
+  'mention.anchorId', 'mention.creatorId', 'mention.slugId',
+  'orderedList.start', 'orderedList.type', 'paragraph.indent',
+  'pdf.attachmentId', 'pdf.height', 'pdf.placeholder', 'pdf.size', 'pdf.width',
+  'tableCell.backgroundColor', 'tableCell.backgroundColorName', 'tableCell.colspan',
+  'tableCell.colwidth', 'tableCell.rowspan',
+  'tableHeader.backgroundColor', 'tableHeader.backgroundColorName', 'tableHeader.colspan',
+  'tableHeader.colwidth', 'tableHeader.rowspan',
+  'video.align', 'video.aspectRatio', 'video.attachmentId', 'video.placeholder', 'video.size',
+  'youtube.align', 'youtube.height', 'youtube.width',
+]);
+
+// ── MARK attribute-value coverage ───────────────────────────────────────────
+// Marks are fuzzed by the text generator (text-arbitraries.ts markedTextRunArb),
+// not the node OVERRIDES table, so their value-fuzz coverage is tracked with this
+// separate registry — otherwise the "no invisible coverage hole" guarantee would
+// hold for node attrs only, and a new mark attr (or a new attributed mark) would
+// silently escape the fuzz set. Every schema mark attr must be in exactly one of:
+//   MARK_ATTR_FUZZED    — actually driven at a non-default value by the generator;
+//   MARK_ATTR_ALLOWLIST — deliberately not value-fuzzed, with a reason.
+const MARK_ATTR_FUZZED = new Set<string>([
+  'mark:link.href', // markedTextRunArb sets a random webUrl href
+  'mark:link.title', // ...and an optional letter-bearing title
+  'mark:highlight.color', // highlight mark carries a generated color
+  'mark:textStyle.color', // textStyle mark carries a generated color
+  'mark:comment.commentId', // comment anchor id (alphanumeric token)
+  'mark:comment.resolved', // comment resolved flag (rides only when true)
+]);
+const MARK_ATTR_ALLOWLIST = new Set<string>([
+  // link presentational/routing attrs: not part of the markdown link surface the
+  // converter emits (it round-trips href + title only), so there is no
+  // non-default value to assert here — a deferred concern for a link-specific
+  // fixture, not the flat generative pass.
+  'mark:link.internal',
+  'mark:link.target',
+  'mark:link.rel',
+  'mark:link.class',
+]);
+
+// Each run does a real convert + marked + jsdom parse (~ms). Give ample headroom
+// so the suite is deterministic regardless of parallel worker load (like the
+// sibling property file).
+vi.setConfig({ testTimeout: 30000 });
+
+// ---------------------------------------------------------------------------
+// #351 PR 1 — GENERATIVE (property-based) round-trip over FLAT (single-node)
+// documents at the ATTRIBUTE level.
+//
+// We assert three invariants for ANY generated valid flat document `d`
+// (pmToMd = convertProseMirrorToMarkdown, mdToPm = markdownToProseMirror):
+//
+//   P1 — semantic round-trip (nothing lost):
+//        docsCanonicallyEqual(await mdToPm(pmToMd(d)), d) === true
+//   P2 — byte fixpoint (anti "GS-EDIT-REVERT" churn):
+//        pmToMd(await mdToPm(pmToMd(d))) === pmToMd(d)
+//   P3 — totality: neither converter throws; bounded.
+//
+// The generators are schema-DERIVED (attribute lists come from
+// schema.nodes[type].spec.attrs) and stay inside the round-trip-supported space
+// proven empirically by probing the live converter (see attr-arbitraries.ts and
+// text-arbitraries.ts). P1 runs over the safe attribute space; P2/P3 run over
+// the wider 'fuzz' space that also injects degenerate attribute states, which
+// P2 tolerates via a one-time first-pass normalization and P3 via totality only.
+// ---------------------------------------------------------------------------
+
+// Fixed seed so every failure is reproducible; fast-check also prints the
+// shrunk counterexample. numRuns starts modest to keep CI under budget — the
+// issue's CI target is ~300-500 per property; the nightly / PR 3 will crank
+// this up further. Each property runs over the UNION (fc.oneof) of all flat
+// node generators, so the runs are shared across node types (one test per
+// property keeps the jsdom import cost and memory bounded — a per-generator ×
+// per-property matrix is ~200 heavy tests that OOMs the worker).
+const SEED = 20250705;
+const NUM_RUNS = 300;
+
+const P1_GENERATORS = buildGenerators('p1');
+const FUZZ_GENERATORS = buildGenerators('fuzz');
+
+// Union arbitraries: a single draw picks one node generator, then a document
+// from it. On failure fast-check prints the shrunk counterexample doc, which
+// names the offending node type directly.
+const p1Union = fc.oneof(...P1_GENERATORS.map((g) => g.arb));
+const fuzzUnion = fc.oneof(...FUZZ_GENERATORS.map((g) => g.arb));
+
+async function roundTrip(doc: unknown): Promise<{ md1: string; md2: string; doc2: any }> {
+  const md1 = convertProseMirrorToMarkdown(doc);
+  const doc2 = await markdownToProseMirror(md1);
+  const md2 = convertProseMirrorToMarkdown(doc2);
+  return { md1, md2, doc2 };
+}
+
+describe('#351 flat generative round-trip — completeness contract', () => {
+  it('every schema node and mark is covered by a generator or explicitly allowlisted', () => {
+    const covered = coveredTypes();
+    const uncovered: string[] = [];
+
+    for (const nodeType of Object.keys(schema.nodes)) {
+      if (covered.has(nodeType)) continue;
+      if (nodeType in KNOWN_UNCOVERED) continue;
+      uncovered.push(`node:${nodeType}`);
+    }
+    for (const markType of Object.keys(schema.marks)) {
+      if (covered.has(`mark:${markType}`)) continue;
+      if (markType in KNOWN_UNCOVERED) continue;
+      uncovered.push(`mark:${markType}`);
+    }
+
+    // A new node/mark added to the schema with no generator AND no allowlist
+    // entry MUST turn this test red — that is the whole point (no silent blind
+    // spots).
+    expect(
+      uncovered,
+      `these schema types have no generator and no KNOWN_UNCOVERED reason:\n  ${uncovered.join(
+        '\n  ',
+      )}`,
+    ).toEqual([]);
+  });
+
+  it('every KNOWN_UNCOVERED entry is a real schema type (no stale allowlist rows)', () => {
+    const all = new Set([...Object.keys(schema.nodes), ...Object.keys(schema.marks)]);
+    for (const t of Object.keys(KNOWN_UNCOVERED)) {
+      expect(all.has(t), `stale KNOWN_UNCOVERED entry: ${t}`).toBe(true);
+    }
+  });
+
+  it('every attribute is value-fuzzed OR explicitly allowlisted (no invisible hole)', () => {
+    // Makes the "generic-frozen" coverage hole VISIBLE: any schema attr not
+    // exercised at a non-default value must be a KNOWN entry in the allowlist.
+    // A new attr (or one that loses its `arb`) that falls into the not-fuzzed
+    // bucket without an allowlist row turns this red — no silent blind spots.
+    const unaccounted: string[] = [];
+    for (const key of allSchemaAttrKeys()) {
+      const i = key.indexOf('.');
+      const fuzzed = attrIsValueFuzzed(key.slice(0, i), key.slice(i + 1));
+      if (!fuzzed && !ATTR_VALUE_FUZZ_ALLOWLIST.has(key)) unaccounted.push(key);
+    }
+    expect(
+      unaccounted,
+      `these attrs are not value-fuzzed and not in ATTR_VALUE_FUZZ_ALLOWLIST:\n  ${unaccounted.join(
+        '\n  ',
+      )}`,
+    ).toEqual([]);
+  });
+
+  it('the attribute allowlist has no stale rows (every entry is really not-fuzzed)', () => {
+    const notFuzzed = new Set(
+      allSchemaAttrKeys().filter((key) => {
+        const i = key.indexOf('.');
+        return !attrIsValueFuzzed(key.slice(0, i), key.slice(i + 1));
+      }),
+    );
+    for (const key of ATTR_VALUE_FUZZ_ALLOWLIST) {
+      expect(
+        notFuzzed.has(key),
+        `stale allowlist row (attr is now value-fuzzed, remove it): ${key}`,
+      ).toBe(true);
+    }
+  });
+
+  it('every MARK attribute is value-fuzzed OR allowlisted (no invisible hole)', () => {
+    // The node guard above covers node attrs; marks are fuzzed by the text
+    // generator, so their coverage is tracked separately. A new mark attr (or a
+    // newly-attributed mark) that lands in neither set turns this red.
+    const unaccounted: string[] = [];
+    for (const key of allSchemaMarkAttrKeys()) {
+      if (!MARK_ATTR_FUZZED.has(key) && !MARK_ATTR_ALLOWLIST.has(key)) {
+        unaccounted.push(key);
+      }
+    }
+    expect(
+      unaccounted,
+      `these mark attrs are neither in MARK_ATTR_FUZZED nor MARK_ATTR_ALLOWLIST:\n  ${unaccounted.join(
+        '\n  ',
+      )}`,
+    ).toEqual([]);
+  });
+
+  it('the MARK fuzz/allowlist sets have no stale rows (every entry is a real schema mark attr)', () => {
+    const all = new Set(allSchemaMarkAttrKeys());
+    for (const key of [...MARK_ATTR_FUZZED, ...MARK_ATTR_ALLOWLIST]) {
+      expect(all.has(key), `stale mark-attr registry row: ${key}`).toBe(true);
+    }
+  });
+});
+
+describe('#351 flat generative round-trip — properties', () => {
+  it('generator validity: every generated doc passes schema.check()', () => {
+    // A generator that emits an invalid ProseMirror document is a GENERATOR bug.
+    fc.assert(
+      fc.property(fuzzUnion, (doc) => {
+        schema.nodeFromJSON(doc).check(); // throws on an invalid doc
+        return true;
+      }),
+      { numRuns: NUM_RUNS, seed: SEED },
+    );
+  });
+
+  it('P1 — semantic round-trip: docsCanonicallyEqual(mdToPm(pmToMd(d)), d)', async () => {
+    await fc.assert(
+      fc.asyncProperty(p1Union, async (doc) => {
+        const { doc2 } = await roundTrip(doc);
+        if (!docsCanonicallyEqual(doc2, doc)) {
+          // Surface the precise divergence in the failure message.
+          const div = firstDivergence(
+            JSON.parse(JSON.stringify(canonicalizeContent(doc2))),
+            JSON.parse(JSON.stringify(canonicalizeContent(doc))),
+          );
+          throw new Error(
+            `P1 divergence @ ${div?.path}: got=${JSON.stringify(div?.a)} want=${JSON.stringify(div?.b)}`,
+          );
+        }
+      }),
+      { numRuns: NUM_RUNS, seed: SEED },
+    );
+  });
+
+  it('P2 — byte fixpoint: pmToMd(mdToPm(pmToMd(d))) === pmToMd(d)', async () => {
+    await fc.assert(
+      fc.asyncProperty(fuzzUnion, async (doc) => {
+        const { md1, md2 } = await roundTrip(doc);
+        expect(md2).toBe(md1);
+      }),
+      { numRuns: NUM_RUNS, seed: SEED },
+    );
+  });
+
+  it('P3 — totality: neither converter throws', async () => {
+    await fc.assert(
+      fc.asyncProperty(fuzzUnion, async (doc) => {
+        // Throwing here fails the property; fast-check shrinks to a minimal doc.
+        await roundTrip(doc);
+      }),
+      { numRuns: NUM_RUNS, seed: SEED },
+    );
+  });
+});

packages/prosemirror-markdown/test/generative/node-generators.ts

@@ -0,0 +1,310 @@
+/**
+ * Flat single-node document generators (#351, PR 1).
+ *
+ * For every schema node type that can stand alone, a fast-check arbitrary
+ * producing `{ type:'doc', content:[ <the target node> ] }` with generated attrs
+ * (via nodeAttrsArb) and the minimal REQUIRED immediate children the schema
+ * demands (a heading's inline text, a listItem's one paragraph, a table's
+ * minimal rows, details' summary+content, a callout's one paragraph). Kept
+ * FLAT: a single target node, no deep nesting — nested structural generation is
+ * PR 2.
+ *
+ * The `mode` threads through to the attribute arbitraries:
+ *   - 'p1'   : the round-trip-safe attribute space (P1 semantic round-trip).
+ *   - 'fuzz' : adds degenerate attribute states (P2 byte-fixpoint tolerates the
+ *              one-time normalization; P3 only needs totality).
+ *
+ * A COMPLETENESS CONTRACT (see flat-roundtrip.property.test.ts) enumerates the
+ * whole schema and asserts every node/mark is EITHER produced by a generator
+ * here OR listed in KNOWN_UNCOVERED with a reason — so a new schema type with no
+ * generator turns the suite RED.
+ */
+import fc from 'fast-check';
+import { type AttrMode, nodeAttrsArb } from './attr-arbitraries.js';
+import {
+  inlineContentArb,
+  headingInlineContentArb,
+  plainInlineContentArb,
+  phraseArb,
+  markedTextRunArb,
+} from './text-arbitraries.js';
+
+const doc = (node: any) => ({ type: 'doc', content: [node] });
+const para = (content: any[]) => ({ type: 'paragraph', content });
+
+/** A named flat-document generator. */
+export interface NamedGen {
+  name: string;
+  arb: fc.Arbitrary<any>;
+}
+
+// ---------------------------------------------------------------------------
+// Per-target generators, each a function of mode.
+// ---------------------------------------------------------------------------
+
+const gen = {
+  paragraph: (m: AttrMode) =>
+    fc.tuple(nodeAttrsArb('paragraph', m), inlineContentArb).map(([attrs, content]) =>
+      doc({ type: 'paragraph', attrs, content }),
+    ),
+
+  heading: (m: AttrMode) =>
+    fc.tuple(nodeAttrsArb('heading', m), headingInlineContentArb).map(([attrs, content]) =>
+      doc({ type: 'heading', attrs, content }),
+    ),
+
+  blockquote: (_m: AttrMode) =>
+    inlineContentArb.map((content) => doc({ type: 'blockquote', content: [para(content)] })),
+
+  bulletList: (_m: AttrMode) =>
+    fc
+      .array(inlineContentArb, { minLength: 1, maxLength: 3 })
+      .map((items) =>
+        doc({
+          type: 'bulletList',
+          content: items.map((c) => ({ type: 'listItem', content: [para(c)] })),
+        }),
+      ),
+
+  orderedList: (m: AttrMode) =>
+    fc
+      .tuple(nodeAttrsArb('orderedList', m), fc.array(inlineContentArb, { minLength: 1, maxLength: 3 }))
+      .map(([attrs, items]) =>
+        doc({
+          type: 'orderedList',
+          attrs,
+          content: items.map((c) => ({ type: 'listItem', content: [para(c)] })),
+        }),
+      ),
+
+  taskList: (m: AttrMode) =>
+    fc
+      .array(fc.tuple(nodeAttrsArb('taskItem', m), inlineContentArb), { minLength: 1, maxLength: 3 })
+      .map((items) =>
+        doc({
+          type: 'taskList',
+          content: items.map(([attrs, c]) => ({ type: 'taskItem', attrs, content: [para(c)] })),
+        }),
+      ),
+
+  codeBlock: (m: AttrMode) =>
+    fc
+      .tuple(
+        nodeAttrsArb('codeBlock', m),
+        // A fenced code block always re-imports with a TRAILING NEWLINE in its
+        // text (empirically confirmed). Author the newline so the doc is already
+        // at the round-trip fixpoint (supported-space shaping, not a masked bug).
+        fc.array(phraseArb, { minLength: 1, maxLength: 3 }).map((lines) => lines.join('\n') + '\n'),
+      )
+      .map(([attrs, code]) =>
+        doc({ type: 'codeBlock', attrs, content: [{ type: 'text', text: code }] }),
+      ),
+
+  horizontalRule: (_m: AttrMode) => fc.constant(doc({ type: 'horizontalRule' })),
+
+  pageBreak: (_m: AttrMode) => fc.constant(doc({ type: 'pageBreak' })),
+
+  image: (m: AttrMode) => nodeAttrsArb('image', m).map((attrs) => doc({ type: 'image', attrs })),
+
+  callout: (m: AttrMode) =>
+    fc.tuple(nodeAttrsArb('callout', m), inlineContentArb).map(([attrs, content]) =>
+      doc({ type: 'callout', attrs, content: [para(content)] }),
+    ),
+
+  mathBlock: (m: AttrMode) =>
+    nodeAttrsArb('mathBlock', m).map((attrs) => doc({ type: 'mathBlock', attrs })),
+
+  details: (m: AttrMode) =>
+    fc
+      .tuple(nodeAttrsArb('details', m), plainInlineContentArb, inlineContentArb)
+      .map(([attrs, summary, body]) =>
+        doc({
+          type: 'details',
+          attrs,
+          content: [
+            { type: 'detailsSummary', content: summary },
+            { type: 'detailsContent', content: [para(body)] },
+          ],
+        }),
+      ),
+
+  table: (_m: AttrMode) =>
+    fc.integer({ min: 1, max: 3 }).chain((cols) => {
+      // GFM alignment is column-wide (encoded in the header separator), so a
+      // column's alignment must be identical on the header and every body cell,
+      // else the second export re-aligns and churns. Pick ONE align per column.
+      const alignsArb = fc.array(fc.constantFrom(undefined, 'left', 'center', 'right'), {
+        minLength: cols,
+        maxLength: cols,
+      });
+      const cell = (header: boolean, align?: string) =>
+        phraseArb.map((t) => ({
+          type: header ? 'tableHeader' : 'tableCell',
+          // colspan/rowspan pinned to 1 (GFM cannot express spans); optional
+          // column-consistent align.
+          attrs: { colspan: 1, rowspan: 1, ...(align ? { align } : {}) },
+          content: [para([{ type: 'text', text: t }])],
+        }));
+      return alignsArb.chain((aligns) => {
+        const headerRow = fc
+          .tuple(...aligns.map((a) => cell(true, a)))
+          .map((cells) => ({ type: 'tableRow', content: cells }));
+        const bodyRow = fc
+          .tuple(...aligns.map((a) => cell(false, a)))
+          .map((cells) => ({ type: 'tableRow', content: cells }));
+        return fc
+          .tuple(headerRow, fc.array(bodyRow, { minLength: 1, maxLength: 2 }))
+          .map(([h, body]) => doc({ type: 'table', content: [h, ...body] }));
+      });
+    }),
+
+  columns: (m: AttrMode) =>
+    // Couple the column count to the layout so the two stay consistent
+    // (two_equal/left_sidebar/right_sidebar -> 2, three_equal -> 3).
+    fc
+      .constantFrom('two_equal', 'three_equal', 'left_sidebar', 'right_sidebar')
+      .chain((layout) => {
+        const count = layout === 'three_equal' ? 3 : 2;
+        return fc
+          .tuple(
+            nodeAttrsArb('columns', m, { layout, widthMode: 'normal' }),
+            fc.array(inlineContentArb, { minLength: count, maxLength: count }),
+          )
+          .map(([attrs, bodies]) =>
+            doc({
+              type: 'columns',
+              attrs,
+              content: bodies.map((c) => ({ type: 'column', content: [para(c)] })),
+            }),
+          );
+      }),
+
+  subpages: (m: AttrMode) =>
+    nodeAttrsArb('subpages', m).map((attrs) => doc({ type: 'subpages', attrs })),
+
+  audio: (m: AttrMode) => nodeAttrsArb('audio', m).map((attrs) => doc({ type: 'audio', attrs })),
+  video: (m: AttrMode) => nodeAttrsArb('video', m).map((attrs) => doc({ type: 'video', attrs })),
+  pdf: (m: AttrMode) => nodeAttrsArb('pdf', m).map((attrs) => doc({ type: 'pdf', attrs })),
+  youtube: (m: AttrMode) => nodeAttrsArb('youtube', m).map((attrs) => doc({ type: 'youtube', attrs })),
+  embed: (m: AttrMode) => nodeAttrsArb('embed', m).map((attrs) => doc({ type: 'embed', attrs })),
+  drawio: (m: AttrMode) => nodeAttrsArb('drawio', m).map((attrs) => doc({ type: 'drawio', attrs })),
+  excalidraw: (m: AttrMode) =>
+    nodeAttrsArb('excalidraw', m).map((attrs) => doc({ type: 'excalidraw', attrs })),
+  attachment: (m: AttrMode) =>
+    nodeAttrsArb('attachment', m).map((attrs) => doc({ type: 'attachment', attrs })),
+  htmlEmbed: (m: AttrMode) =>
+    nodeAttrsArb('htmlEmbed', m).map((attrs) => doc({ type: 'htmlEmbed', attrs })),
+  pageEmbed: (m: AttrMode) =>
+    nodeAttrsArb('pageEmbed', m).map((attrs) => doc({ type: 'pageEmbed', attrs })),
+  transclusionReference: (m: AttrMode) =>
+    nodeAttrsArb('transclusionReference', m).map((attrs) =>
+      doc({ type: 'transclusionReference', attrs }),
+    ),
+
+  transclusionSource: (m: AttrMode) =>
+    fc.tuple(nodeAttrsArb('transclusionSource', m), inlineContentArb).map(([attrs, content]) =>
+      doc({ type: 'transclusionSource', attrs, content: [para(content)] }),
+    ),
+
+  // A footnote reference PLUS its definition (the reference has no standalone
+  // markdown form without its definition — see KNOWN_UNCOVERED note for the
+  // bare reference). Both carry the same id. The definition body uses
+  // headingInlineContentArb (NO hard breaks): a footnote is serialized inline as
+  // `^[...]`, so a hard break inside it collapses to a single space on re-parse
+  // (empirically confirmed) — that is the container's markdown limitation, not
+  // an attribute-level concern. The reference-bearing paragraph is a NORMAL
+  // paragraph and keeps the full inline corpus.
+  footnotes: (m: AttrMode) =>
+    fc.tuple(fc.constantFrom('fn1', 'fn2', 'note'), inlineContentArb, headingInlineContentArb).map(
+      ([id, refText, noteBody]) => ({
+        type: 'doc',
+        content: [
+          para([...refText, { type: 'footnoteReference', attrs: { id } }]),
+          {
+            type: 'footnotesList',
+            content: [{ type: 'footnoteDefinition', attrs: { id }, content: [para(noteBody)] }],
+          },
+        ],
+      }),
+    ),
+
+  // ── inline targets wrapped in a paragraph ────────────────────────────────
+  mention: (m: AttrMode) =>
+    nodeAttrsArb('mention', m).map((attrs) => doc(para([{ type: 'mention', attrs }]))),
+
+  mathInline: (m: AttrMode) =>
+    fc.tuple(phraseArb, nodeAttrsArb('mathInline', m)).map(([t, attrs]) =>
+      doc(para([{ type: 'text', text: t }, { type: 'mathInline', attrs }])),
+    ),
+
+  status: (m: AttrMode) =>
+    nodeAttrsArb('status', m).map((attrs) => doc(para([{ type: 'status', attrs }]))),
+
+  hardBreak: (_m: AttrMode) =>
+    fc.tuple(phraseArb, phraseArb).map(([a, b]) =>
+      doc(para([{ type: 'text', text: a }, { type: 'hardBreak' }, { type: 'text', text: b }])),
+    ),
+
+  // ── marks: a paragraph of marked runs (covers every mark type) ───────────
+  marksOnText: (_m: AttrMode) =>
+    fc.array(markedTextRunArb, { minLength: 1, maxLength: 5 }).map((runs) => {
+      // Merge adjacent same-mark runs (see text-arbitraries.normalizeInline).
+      const out: any[] = [];
+      for (const r of runs) {
+        const prev = out[out.length - 1];
+        if (prev && JSON.stringify(prev.marks ?? []) === JSON.stringify(r.marks ?? [])) {
+          prev.text += r.text;
+        } else out.push({ ...r });
+      }
+      return doc(para(out));
+    }),
+};
+
+/** Build the full list of named generators for a given mode. */
+export function buildGenerators(mode: AttrMode): NamedGen[] {
+  return Object.entries(gen).map(([name, f]) => ({ name, arb: f(mode) }));
+}
+
+// ---------------------------------------------------------------------------
+// Completeness contract support.
+// ---------------------------------------------------------------------------
+
+/**
+ * Schema node/mark types deliberately NOT covered by a P1/P2 generator, each
+ * with a one-line reason. Excluding a type means it is kept OUT of the round-
+ * trip generators — it does NOT weaken any property.
+ *
+ * NOTE (empirical): the candidates the issue flagged for review — pageEmbed,
+ * subpages, transclusionSource/Reference, mention, status — were PROBED against
+ * the live converter and DO round-trip P1/P2 with placeholder ids, so they are
+ * COVERED by real generators rather than allowlisted here. The allowlist below
+ * holds only types with no standalone flat generator by construction.
+ */
+export const KNOWN_UNCOVERED: Record<string, string> = {
+  // The root node; it is the wrapper every generated doc already is, never a
+  // "target" content node, so it has no standalone generator of its own.
+  doc: 'the document root wrapper, not a content node with a standalone generator',
+};
+
+/** Recursively collect every node type and `mark:<type>` under a tree. */
+export function collectTypes(node: any, seen = new Set<string>()): Set<string> {
+  if (!node || typeof node !== 'object') return seen;
+  if (node.type) seen.add(node.type);
+  for (const m of node.marks ?? []) if (m?.type) seen.add(`mark:${m.type}`);
+  for (const c of node.content ?? []) collectTypes(c, seen);
+  return seen;
+}
+
+/**
+ * Sample every generator and return the union of node/mark types they produce.
+ * Deterministic (fixed seed) so the completeness contract is stable.
+ */
+export function coveredTypes(seed = 12345, perGen = 60): Set<string> {
+  const seen = new Set<string>();
+  for (const { arb } of buildGenerators('p1')) {
+    for (const sample of fc.sample(arb, { numRuns: perGen, seed })) {
+      collectTypes(sample, seen);
+    }
+  }
+  return seen;
+}

packages/prosemirror-markdown/test/generative/text-arbitraries.ts

@@ -0,0 +1,258 @@
+/**
+ * Hostile inline-text corpus for the generative flat-document round-trip suite
+ * (#351, PR 1).
+ *
+ * These arbitraries are a DIRECT PORT of the "supported space" guardrails that
+ * `test/markdown-roundtrip.property.test.ts` proved empirically against the live
+ * converter. That file's long header documents WHY each guardrail exists; rather
+ * than re-derive them, we reuse the exact same shapes here so the attribute-level
+ * generative suite inherits the same byte-stable text space. Each guardrail is
+ * cited back to that file below.
+ *
+ * The corpus deliberately spans the CommonMark / canon hostile alphabet
+ * (`* _ [ ] ( ) { } | < > & # ! ~ = + -`), unicode / emoji / RTL, and the legal
+ * mark combinations on runs (including the `code` mark, which the schema's
+ * `excludes: "_"` makes suppress every co-occurring mark — so it is never
+ * combined with another mark in the byte-stable space).
+ */
+import fc from 'fast-check';
+
+// ---------------------------------------------------------------------------
+// Words and the hostile special-character alphabet.
+// (Ported from markdown-roundtrip.property.test.ts, "Inline text arbitraries".)
+// ---------------------------------------------------------------------------
+
+/** Alphanumeric "word" (no markdown-significant characters). Length 1..6. */
+export const wordArb = fc
+  .stringMatching(/^[A-Za-z0-9]{1,6}$/)
+  .filter((w) => w.length > 0);
+
+/**
+ * A SINGLE markdown-significant character, emitted only as an isolated,
+ * space-flanked token. Every char the task calls out plus a few more; each was
+ * verified byte-stable in this position by the sibling property test.
+ *
+ * NOTE: the backtick (`) is DELIBERATELY excluded from free-floating plain text
+ * (it is a code-span delimiter that re-pairs globally). It is exercised only via
+ * the `code` mark and code blocks — see markdown-roundtrip.property.test.ts.
+ */
+export const specialCharArb = fc.constantFrom(
+  '*', '_', '[', ']', '(', ')', '{', '}', '|', '<', '>', '&', '#', '!', '~', '=', '+', '-',
+);
+
+// A pinch of unicode / emoji / RTL, always word-like (no markdown specials) so
+// it stays inside the space-flanked corpus. Kept letter/emoji-bearing so it is
+// never coerced to a number (see letterPhraseArb rationale).
+export const unicodeWordArb = fc.constantFrom(
+  'café', 'naïve', 'Zürich', 'Москва', 'こんにちは', '你好', '😀', '🚀x', 'مرحبا', 'שלום',
+);
+
+/**
+ * A "safe special" text string: a space-joined sequence of tokens that always
+ * BEGINS and ENDS with an alphanumeric word, with any isolated special chars (or
+ * unicode words) confined to the MIDDLE, each space-flanked by words.
+ *
+ * Both boundary guarantees matter (verbatim from the sibling test):
+ *   * Leading word: the line never opens with a block/inline trigger
+ *     (">", "*", "-", "#", "1." ...).
+ *   * Trailing word: adjacent text runs CONCATENATE with no separator, so a run
+ *     ending in a bare "<" beside a run starting with a letter would form a fake
+ *     HTML tag. Ending every run with a word keeps every special internal and
+ *     space-flanked even after concatenation.
+ */
+export const safeTextArb: fc.Arbitrary<string> = fc
+  .tuple(
+    wordArb,
+    fc.array(fc.oneof(wordArb, specialCharArb, unicodeWordArb), {
+      minLength: 0,
+      maxLength: 3,
+    }),
+    wordArb,
+  )
+  .map(([first, middle, last]) => [first, ...middle, last].join(' '));
+
+/**
+ * A plain alphanumeric phrase (1..3 words) for places where even isolated
+ * specials are not wanted (e.g. code-block language, mention labels, status
+ * text, table cells rendered on the plain-markdown path).
+ */
+export const phraseArb: fc.Arbitrary<string> = fc
+  .array(wordArb, { minLength: 1, maxLength: 3 })
+  .map((ws) => ws.join(' '));
+
+/**
+ * A phrase guaranteed to contain at least one letter. Used for image/media alt
+ * text and link titles: a PURELY numeric alt/title (e.g. "0") is parsed back as
+ * a NUMBER and then dropped by the converter's `value || ""` coercion — not
+ * byte-stable. A letter anywhere keeps it a string. (Ported verbatim.)
+ */
+export const letterPhraseArb: fc.Arbitrary<string> = fc
+  .tuple(
+    fc.stringMatching(/^[A-Za-z]{1,4}$/),
+    fc.array(wordArb, { minLength: 0, maxLength: 2 }),
+  )
+  .map(([head, rest]) => [head, ...rest].join(' '));
+
+/** A paren/space-free URL — safe inside markdown link/image `(...)` syntax. */
+export const urlArb: fc.Arbitrary<string> = fc
+  .webUrl()
+  .filter((u) => !/[()\s]/.test(u));
+
+// ---------------------------------------------------------------------------
+// Marked inline runs.
+// (Ported from markdown-roundtrip.property.test.ts "markedTextRunArb".)
+// ---------------------------------------------------------------------------
+
+/**
+ * A text run with an OPTIONAL single non-code formatting mark (bold/italic/
+ * strike/underline/superscript/subscript/spoiler), or a SOLE `code` mark, or a
+ * link, or an inline comment anchor. `code` is NEVER combined with another mark
+ * in the byte-stable space (that combination is a documented converter
+ * limitation — the schema's `code` mark declares `excludes: "_"`). Marks wrap
+ * `safeTextArb`, which stays stable even when it contains isolated specials.
+ *
+ * The mark set here is broadened past the sibling test's {bold,italic,strike}
+ * to also cover underline / superscript / subscript / spoiler / textStyle /
+ * highlight (all single, non-code marks), so the marks-on-text generator
+ * exercises every mark the schema declares except the deliberately-excluded
+ * `code`+other combination.
+ */
+export const markedTextRunArb: fc.Arbitrary<any> = fc.oneof(
+  // Plain text.
+  safeTextArb.map((t) => ({ type: 'text', text: t })),
+  // Single formatting mark (attribute-free marks).
+  fc
+    .tuple(
+      safeTextArb,
+      fc.constantFrom('bold', 'italic', 'strike', 'underline', 'superscript', 'subscript', 'spoiler'),
+    )
+    .map(([t, m]) => ({ type: 'text', text: t, marks: [{ type: m }] })),
+  // highlight with a color attr.
+  fc
+    .tuple(safeTextArb, fc.constantFrom('#ffcc00', '#a0e0ff', 'yellow'))
+    .map(([t, color]) => ({ type: 'text', text: t, marks: [{ type: 'highlight', attrs: { color } }] })),
+  // textStyle with a color attr.
+  fc
+    .tuple(safeTextArb, fc.constantFrom('#123456', '#ff0000', '#00aa88'))
+    .map(([t, color]) => ({ type: 'text', text: t, marks: [{ type: 'textStyle', attrs: { color } }] })),
+  // Sole code mark (backtick span). safeTextArb is backtick-free, so the span
+  // content cannot contain an inner backtick.
+  safeTextArb.map((t) => ({ type: 'text', text: t, marks: [{ type: 'code' }] })),
+  // Link with safe text, a paren/space-free href, optionally a letter-bearing
+  // title (a purely numeric title is coerced to a number and dropped).
+  fc
+    .tuple(phraseArb, urlArb, fc.option(letterPhraseArb, { nil: undefined }))
+    .map(([t, href, title]) => ({
+      type: 'text',
+      text: t,
+      marks: [{ type: 'link', attrs: title ? { href, title } : { href } }],
+    })),
+  // Inline comment anchor: a span[data-comment-id] that must survive byte-for-
+  // byte. commentId is an alphanumeric token; `resolved` rides only when true.
+  fc
+    .tuple(safeTextArb, fc.stringMatching(/^[A-Za-z0-9]{4,10}$/), fc.boolean())
+    .map(([t, commentId, resolved]) => ({
+      type: 'text',
+      text: t,
+      marks: [
+        { type: 'comment', attrs: resolved ? { commentId, resolved: true } : { commentId } },
+      ],
+    })),
+);
+
+// ---------------------------------------------------------------------------
+// Inline atoms and inline-content assembly.
+// (Ported from markdown-roundtrip.property.test.ts.)
+// ---------------------------------------------------------------------------
+
+/** Inline math node carrying LaTeX that includes the `a < b` the task asks for. */
+export const mathInlineArb: fc.Arbitrary<any> = fc
+  .constantFrom('a < b', 'x^2 + y^2', 'a < b < c', '\\frac{1}{2}', 'E = mc^2')
+  .map((text) => ({ type: 'mathInline', attrs: { text } }));
+
+/** Mention node; label/id/entity are plain phrases / uuids. */
+export const mentionArb: fc.Arbitrary<any> = fc
+  .tuple(phraseArb, fc.uuid(), fc.uuid())
+  .map(([label, id, entityId]) => ({
+    type: 'mention',
+    attrs: { id, label, entityType: 'user', entityId },
+  }));
+
+export const hardBreakArb: fc.Arbitrary<any> = fc.constant({ type: 'hardBreak' });
+
+const sameMarks = (a: any[] | undefined, b: any[] | undefined): boolean =>
+  JSON.stringify(a ?? []) === JSON.stringify(b ?? []);
+
+/**
+ * Canonicalize a generated inline-content array the way ProseMirror stores it,
+ * then trim the markdown-fragile edges. (Ported verbatim from
+ * markdown-roundtrip.property.test.ts "normalizeInline":)
+ *   1) MERGE adjacent text runs with IDENTICAL marks (the editor coalesces
+ *      them; split same-mark runs export to ambiguous "**a****b**").
+ *   2) Collapse CONSECUTIVE hard breaks (two render a blank line marked eats).
+ *   3) Drop a TRAILING hard break (removed by the converter's .trim()).
+ */
+export function normalizeInline(nodes: any[]): any[] {
+  const out: any[] = [];
+  for (const node of nodes) {
+    const prev = out[out.length - 1];
+    if (node.type === 'hardBreak' && prev && prev.type === 'hardBreak') continue;
+    if (
+      node.type === 'text' &&
+      prev &&
+      prev.type === 'text' &&
+      sameMarks(prev.marks, node.marks)
+    ) {
+      prev.text += node.text;
+      continue;
+    }
+    out.push(node.type === 'text' ? { ...node } : node);
+  }
+  while (out.length > 1 && out[out.length - 1].type === 'hardBreak') out.pop();
+  return out;
+}
+
+/**
+ * Inline content for a paragraph: at least one marked text run, optionally with
+ * inline atoms (math/mention) and hard breaks interspersed. Always starts with a
+ * text run so the paragraph never opens with a block trigger. (Ported.)
+ */
+export const inlineContentArb: fc.Arbitrary<any[]> = fc
+  .tuple(
+    markedTextRunArb,
+    fc.array(
+      fc.oneof(
+        { weight: 5, arbitrary: markedTextRunArb },
+        { weight: 1, arbitrary: mathInlineArb },
+        { weight: 1, arbitrary: mentionArb },
+        { weight: 1, arbitrary: hardBreakArb },
+      ),
+      { minLength: 0, maxLength: 4 },
+    ),
+  )
+  .map(([first, rest]) => normalizeInline([first, ...rest]));
+
+/**
+ * Inline content for a HEADING — identical to a paragraph's, but WITHOUT hard
+ * breaks. A hard break inside an ATX heading is not byte-stable (marked splits
+ * the heading). (Ported.)
+ */
+export const headingInlineContentArb: fc.Arbitrary<any[]> = fc
+  .tuple(
+    markedTextRunArb,
+    fc.array(
+      fc.oneof(
+        { weight: 5, arbitrary: markedTextRunArb },
+        { weight: 1, arbitrary: mathInlineArb },
+        { weight: 1, arbitrary: mentionArb },
+      ),
+      { minLength: 0, maxLength: 4 },
+    ),
+  )
+  .map(([first, rest]) => normalizeInline([first, ...rest]));
+
+/** Simple plain-text inline content (single run) for containers rendered on the
+ * raw-HTML path (table cells / column bodies) where fancy inline is undesirable. */
+export const plainInlineContentArb: fc.Arbitrary<any[]> = phraseArb.map((t) => [
+  { type: 'text', text: t },
+]);

patches/ai@6.0.134.patch

@@ -0,0 +1,68 @@
+diff --git a/dist/index.js b/dist/index.js
+index ae447a12f7823ec0a00837ee9f0eb809a610d5f8..a3402b2c2d021ef432cfa76e35d370073d525135 100644
+--- a/dist/index.js
++++ b/dist/index.js
+@@ -6578,9 +6578,19 @@ function createOutputTransformStream(output) {
+         controller.enqueue({ part: chunk, partialOutput: void 0 });
+         return;
+       }
+-      text2 += chunk.text;
+       textChunk += chunk.text;
+       textProviderMetadata = (_a21 = chunk.providerMetadata) != null ? _a21 : textProviderMetadata;
++      if (output == null) {
++        // PATCH(docmost #OOM): no output strategy requested -> publish each
++        // text-delta immediately and do NOT build cumulative partialOutput
++        // snapshots. Unpatched, the default text() output snapshots the ENTIRE
++        // accumulated turn text on every delta (O(n^2) memory) and those
++        // snapshots pile up in the never-consumed leftover tee branch of
++        // DefaultStreamTextResult.baseStream -> heap OOM on long agent turns.
++        publishTextChunk({ controller });
++        return;
++      }
++      text2 += chunk.text;
+       const result = await output.parsePartialOutput({ text: text2 });
+       if (result !== void 0) {
+         const currentJson = JSON.stringify(result.partial);
+@@ -6959,7 +6969,7 @@ var DefaultStreamTextResult = class {
+         })
+       );
+     }
+-    this.baseStream = stream.pipeThrough(createOutputTransformStream(output != null ? output : text())).pipeThrough(eventProcessor);
++    this.baseStream = stream.pipeThrough(createOutputTransformStream(output)).pipeThrough(eventProcessor);
+     const { maxRetries, retry } = prepareRetries({
+       maxRetries: maxRetriesArg,
+       abortSignal
+diff --git a/dist/index.mjs b/dist/index.mjs
+index 663875332e3f9a9bd167c25583c515876f42951b..b840b0502c9894df983e0154805abb80e70e6331 100644
+--- a/dist/index.mjs
++++ b/dist/index.mjs
+@@ -6501,9 +6501,19 @@ function createOutputTransformStream(output) {
+         controller.enqueue({ part: chunk, partialOutput: void 0 });
+         return;
+       }
+-      text2 += chunk.text;
+       textChunk += chunk.text;
+       textProviderMetadata = (_a21 = chunk.providerMetadata) != null ? _a21 : textProviderMetadata;
++      if (output == null) {
++        // PATCH(docmost #OOM): no output strategy requested -> publish each
++        // text-delta immediately and do NOT build cumulative partialOutput
++        // snapshots. Unpatched, the default text() output snapshots the ENTIRE
++        // accumulated turn text on every delta (O(n^2) memory) and those
++        // snapshots pile up in the never-consumed leftover tee branch of
++        // DefaultStreamTextResult.baseStream -> heap OOM on long agent turns.
++        publishTextChunk({ controller });
++        return;
++      }
++      text2 += chunk.text;
+       const result = await output.parsePartialOutput({ text: text2 });
+       if (result !== void 0) {
+         const currentJson = JSON.stringify(result.partial);
+@@ -6882,7 +6892,7 @@ var DefaultStreamTextResult = class {
+         })
+       );
+     }
+-    this.baseStream = stream.pipeThrough(createOutputTransformStream(output != null ? output : text())).pipeThrough(eventProcessor);
++    this.baseStream = stream.pipeThrough(createOutputTransformStream(output)).pipeThrough(eventProcessor);
+     const { maxRetries, retry } = prepareRetries({
+       maxRetries: maxRetriesArg,
+       abortSignal

pnpm-lock.yaml

@@ -44,6 +44,9 @@ overrides:
   ip-address: 10.1.1
 
 patchedDependencies:
+  ai@6.0.134:
+    hash: f60bfc3357e01e1f3978c6c40fdd65aeb33fefaad7179cde8676465b6c5ff4d9
+    path: patches/ai@6.0.134.patch
   scimmy@1.3.5:
     hash: 775d80f86830b2c5dd1a250c9802c10f8fc3da3c7898373de5aa0c23993d1673
     path: patches/scimmy@1.3.5.patch
@@ -543,6 +546,9 @@ importers:
       '@docmost/pdf-inspector':
         specifier: 1.9.6
         version: 1.9.6
+      '@docmost/prosemirror-markdown':
+        specifier: workspace:*
+        version: link:../../packages/prosemirror-markdown
       '@fastify/cookie':
         specifier: ^11.0.2
         version: 11.0.2
@@ -623,10 +629,10 @@ importers:
         version: 8.3.0(socket.io-adapter@2.5.4)
       ai:
         specifier: ^6.0.134
-        version: 6.0.134(zod@4.3.6)
+        version: 6.0.134(patch_hash=f60bfc3357e01e1f3978c6c40fdd65aeb33fefaad7179cde8676465b6c5ff4d9)(zod@4.3.6)
       ai-sdk-ollama:
         specifier: ^3.8.1
-        version: 3.8.1(ai@6.0.134(zod@4.3.6))(zod@4.3.6)
+        version: 3.8.1(ai@6.0.134(patch_hash=f60bfc3357e01e1f3978c6c40fdd65aeb33fefaad7179cde8676465b6c5ff4d9)(zod@4.3.6))(zod@4.3.6)
       bcrypt:
         specifier: ^6.0.0
         version: 6.0.0
@@ -16355,17 +16361,17 @@ snapshots:
 
   agent-base@7.1.4: {}
 
-  ai-sdk-ollama@3.8.1(ai@6.0.134(zod@4.3.6))(zod@4.3.6):
+  ai-sdk-ollama@3.8.1(ai@6.0.134(patch_hash=f60bfc3357e01e1f3978c6c40fdd65aeb33fefaad7179cde8676465b6c5ff4d9)(zod@4.3.6))(zod@4.3.6):
     dependencies:
       '@ai-sdk/provider': 3.0.8
       '@ai-sdk/provider-utils': 4.0.21(zod@4.3.6)
-      ai: 6.0.134(zod@4.3.6)
+      ai: 6.0.134(patch_hash=f60bfc3357e01e1f3978c6c40fdd65aeb33fefaad7179cde8676465b6c5ff4d9)(zod@4.3.6)
       jsonrepair: 3.13.3
       ollama: 0.6.3
     transitivePeerDependencies:
       - zod
 
-  ai@6.0.134(zod@4.3.6):
+  ai@6.0.134(patch_hash=f60bfc3357e01e1f3978c6c40fdd65aeb33fefaad7179cde8676465b6c5ff4d9)(zod@4.3.6):
     dependencies:
       '@ai-sdk/gateway': 3.0.77(zod@4.3.6)
       '@ai-sdk/provider': 3.0.8