@@ -0,0 +1,35 @@
+---
+'@objectstack/spec': minor
+---
+
+A page's `requires` is accepted only on the kinds whose source is compiled at save: `html` and its deprecated alias `jsx`. On a `react`, `full` or `slotted` page, and on a page that omits `kind` (which is `full`), it is refused at parse.
+
+Clause-②: yes (narrowing)
+
+<!-- adr-0087: registered page-requires-non-compiled-kind-removed, page-requires-non-compiled-kind-refused -->
+
+**BREAKING**: an accept-set narrowing on a published authoring surface, shipped as `minor` under the launch-window convention for accept-set narrowings.
+
+**Why.** `requires` is the list of plugin namespaces a page's source uses (ADR-0080 §5). It is derived from the source at save, and its describe has always said "omit it". On an html page, on a server that has the deployment's SDUI component manifest, the metadata save door compiles the source, stores the namespaces it uses as `requires`, and refuses a written list that disagrees. A `react` source is executed at render and never compiled at save, and `full` and `slotted` pages have no source. So on those three kinds nothing derived the key, the Studio page editor dropped it on every save, and its one reader was a load-time warning. `PageSchema` still accepted it there and never told the author it did nothing. The maintainer ruled that the key is accepted only on the compiled kinds.
+
+**What is refused.** `requires` on a page whose `kind` is `react`, `full` or `slotted`, or a page with no `kind`, at the `requires` path. An empty list is refused too, because the key is what is refused, not its contents. The issue's `code` is `custom`, and its message names the key, the page's kind and the compiled kinds. That covers `definePage()`, `PageSchema`, `defineStack` (`STACK_SCHEMA_INVALID`, 422, at `pages.N.requires`), `os validate`, which runs the same stack parse, and the metadata save door (`422 INVALID_METADATA`).
+
+**What stays accepted.** `requires` on an `html` or `jsx` page, byte for byte. The save door still derives it, stores it, and refuses a written list that disagrees. Every page that omits `requires` parses as before, on every kind.
+
+## FROM → TO
+
+| you wrote | write instead |
+|:--|:--|
+| `requires: [...]` on a `kind: 'react'` page | nothing: delete the key. Nothing derived or enforced it |
+| `requires: [...]` on a `kind: 'full'` or `kind: 'slotted'` page, or on a page with no `kind` | nothing: delete the key |
+| `requires: [...]` on a `kind: 'html'` or `kind: 'jsx'` page | unchanged. The platform derives it from the source at save, so omitting it is still the intended authoring |
+
+**The one-line fix: delete `requires` from every page whose `kind` is not `html` or `jsx`.** `os migrate meta --from 17` lists the mechanical edits for existing sources. Stored pages and built artifacts are converted when they are read.
+
+**Who is affected, measured.** No page body authors `requires` on a `react`, `full` or `slotted` page in this repository at `c98a72d69e` (`examples/**`, `packages/apps/**`, `content/docs/**`, `skills/**`, tests and fixtures). Every `requires:` there is the stack-level capability list or an html page in a save-door test. The same holds in cloud (`c5a4c9e6cb`), hotcrm (`5ae524916d`) and objectui (`8366accd13`), per the ruling's census. Deployed metadata was not measured.
+
+### The retirement kit
+
+- **The refusal.** `checkPageRequiresKind`, an exported object-level check attached to `PageSchema` beside `checkPageSourceCompleteness` (`@objectstack/spec/ui`), with `COMPILED_PAGE_KINDS` (`['html', 'jsx']`) as its vocabulary. A downstream mirror that derives its schema from `PageSchema.shape` re-attaches it with `.superRefine(checkPageRequiresKind)`. There is no tombstone and no `RETIRED_KEYS_BY_MAJOR` row, because the key stays live on html pages.
+- **The conversion.** `page-requires-non-compiled-kind-removed` (protocol 18) deletes the key from `react`, `full`, `slotted` and kind-less pages. It is a lossless delete: on those kinds the list never had an effect. It is retired from the load path, so authored sources are refused at parse, while stored rows, built artifacts and `os migrate meta` replay it. Its D3 record is the semantic entry `page-requires-non-compiled-kind-refused`.
+- **The ledgers.** The `requires` describe, its liveness row (`liveness/page.json`) and its form-reconciliation row now say the key exists only on html and jsx pages.
@@ -184,7 +184,7 @@ View filter rule
 | **kind** | `Enum<'full' \| 'slotted' \| 'html' \| 'react' \| 'jsx'>` | optional (default: `"full"`) | Page override mode. full \| slotted = structured authoring; html = author-written constrained JSX compiled (parsed, never executed) to the tree (ADR-0080; the legacy value 'jsx' is a deprecated alias), styled by the registered components' structured props plus a JSON `style` object with hsl(var(--token)) theme colors; react = real-React source executed at render by the runtime (ADR-0081), styled by inline `style` with the same token colors; it runs author JS, so it is gated by a host capability that defaults ON and is disabled server-side via the OS_PAGE_REACT=off env toggle. Do not author Tailwind classes in page source in either tier: `source` is runtime metadata the build-time Tailwind never scans, so utility classNames silently produce no CSS (ADR-0065; ADR-0080 amendment 2026-06-30). |
 | **slots** | `{ header?: object \| object[]; actions?: object \| object[]; alerts?: object \| object[]; highlights?: object \| object[]; … }` | optional | Slot override map for slotted pages |
 | **source** | `string` | optional | Page source text. For kind==='html' (alias 'jsx') it is constrained JSX compiled to the tree by @objectstack/sdui-parser at save time (parse, never execute), styled by the registered components' structured props plus a JSON `style` object with hsl(var(--token)) theme colors. For kind==='react' it is real React/JSX executed at render by @object-ui/react-runtime (trusted tier), styled by inline `style` with the same token colors. Do not author Tailwind classes in page source in either tier: `source` is runtime metadata the build-time Tailwind never scans, so utility classNames silently produce no CSS (ADR-0065; ADR-0080 amendment 2026-06-30). Authoritative over `regions` in both. |
-| **requires** | `string[]` | optional | Plugin namespaces the page's source uses, derived from the source at save — omit it. On a server that has the deployment's SDUI component manifest, saving a kind==='html' page (alias 'jsx') compiles its source and stores the namespaces it uses here; a written list that disagrees with the source is refused (422 INVALID_METADATA, page-requires-disagrees-with-source) — on a draft save it is kept until the draft's publish, which refuses it. At load, a stored page whose list names a plugin no component in that manifest carries is reported, page and plugin named, and is still served. A server with no manifest checks neither and says so once at boot. |
+| **requires** | `string[]` | optional | Plugin namespaces the page's source uses, derived from the source at save — omit it. The key exists only on a kind==='html' page (alias 'jsx'), the kinds whose source is compiled at save; on a 'react', 'full' or 'slotted' page — and a page that omits kind, which is 'full' — it is refused at parse. On a server that has the deployment's SDUI component manifest, saving an html page compiles its source and stores the namespaces it uses here; a written list that disagrees with the source is refused (422 INVALID_METADATA, page-requires-disagrees-with-source) — on a draft save it is kept until the draft's publish, which refuses it. At load, a stored page whose list names a plugin no component in that manifest carries is reported, page and plugin named, and is still served. A server with no manifest checks neither and says so once at boot. |
 | **_lock** | `Enum<'none' \| 'no-overlay' \| 'no-delete' \| 'full'>` | optional | Item-level lock — controls overlay & delete (ADR-0010). |
 | **_lockReason** | `string` | optional | Human-readable reason shown when a write is refused by _lock. |
 | **_lockSource** | `Enum<'artifact' \| 'package' \| 'env-forced'>` | optional | Layer that set _lock (artifact \| package \| env-forced). |
 
@@ -1224,6 +1224,35 @@ describe('html page source compiled at the save door against the SDUI manifest (
             .resolves.toMatchObject({ success: true });
     });
 
+    // [#21459] `requires` exists only on the kinds this door compiles. On any
+    // other kind the spec parse refuses it before the compile runs, so the
+    // refusal is the spec's own issue at `requires` — not a compile finding.
+    it.each(['react', 'full', 'slotted', undefined])(
+        'refuses `requires` on a `%s` page with a 422 at `requires`, and persists nothing (#21459)',
+        async (kind) => {
+            const { protocol, rows } = hostWith(new Map([['sdui-manifest', manifest()]]));
+            const page = {
+                name: 'landing', label: 'Landing', requires: ['ui'],
+                ...(kind === undefined ? {} : { kind }),
+                ...(kind === 'react' ? { source: KNOWN } : {}),
+            };
+            const err = await savePage(protocol, page).catch((e: any) => e);
+            expect(refusal(err)).toEqual({ code: 'INVALID_METADATA', status: 422 });
+            const issues = err.issues.filter((i: any) => i.path === 'requires');
+            expect(issues, JSON.stringify(err.issues)).toHaveLength(1);
+            expect(issues[0].code).toBe('custom');
+            expect(issues[0].message).toContain(`\`kind: '${kind ?? 'full'}'\``);
+            expect(err.issues.some((i: any) => String(i.rule ?? '').startsWith('jsx-'))).toBe(false);
+            expect(pageRows(rows)).toEqual([]);
+        },
+    );
+
+    it('CONTROL: the same `requires` on an html page still saves, and the compile stamps it (#21459)', async () => {
+        const { protocol, rows } = hostWith(new Map([['sdui-manifest', manifest()]]));
+        await expect(savePage(protocol, htmlPage(KNOWN, { requires: ['ui'] }))).resolves.toMatchObject({ success: true });
+        expect(storedPage(rows)?.requires).toEqual(['ui']);
+    });
+
     it('a registered value that is not a manifest is warned about once and compiled against never', async () => {
         const { protocol, rows } = hostWith(new Map([['sdui-manifest', { oops: true }]]));
         await expect(savePage(protocol, htmlPage(UNKNOWN))).resolves.toMatchObject({ success: true });
@@ -1339,6 +1368,35 @@ describe('stored html page `requires` at load and at draft promotion (#20312)',
         expect(loadReports(warn)).toEqual([]);
     });
 
+    // [#21459] A row stored before `requires` was narrowed to the compiled
+    // kinds: a react page carrying the key, which the save door now refuses, so
+    // it is seeded straight into the store. The stored-row seam replays the D2
+    // conversion `page-requires-non-compiled-kind-removed` before anything reads
+    // the body — so the row loads with the key gone and a notice saying so, the
+    // spec check finds nothing to report, and the load report never sees a list.
+    it('at load, a stored react page carrying `requires` is read without it — converted, not reported or badged (#21459)', async () => {
+        const services = new Map<string, unknown>([['sdui-manifest', manifest(false)]]);
+        const { protocol, rows, registered } = hostWith(services);
+        const body = { name: 'workbench', label: 'Workbench', kind: 'react', source: '<Workbench />', requires: ['plugin-kanban'] };
+        rows.set(keyOf({ type: 'page', name: 'workbench', organization_id: null, state: 'active' }), {
+            id: 'r_seed', type: 'page', name: 'workbench', organization_id: null, state: 'active', metadata: JSON.stringify(body),
+        });
+
+        const result = await protocol.loadMetaFromDb();
+
+        expect(result).toMatchObject({ loaded: 1, errors: 0, invalid: 0 });
+        expect(registered).toContainEqual({ type: 'page', name: 'workbench' });
+        const lines = (warn.mock.calls as unknown[][]).map((c) => String(c[0]));
+        const converted = lines.filter((m) => m.includes('stored page/workbench carries a pre-protocol shape'));
+        expect(converted, JSON.stringify(lines)).toHaveLength(1);
+        expect(converted[0]).toContain("ADR-0087 conversion 'page-requires-non-compiled-kind-removed'");
+        expect(converted[0]).toContain('page.requires at pages[0].requires');
+        // The manifest carries no `plugin-kanban`, so an unconverted list WOULD
+        // have been reported — its absence is the conversion's doing.
+        expect(loadReports(warn)).toEqual([]);
+        expect(lines.filter((m) => m.includes('[metadata_spec_invalid]'))).toEqual([]);
+    });
+
     // ── At draft → active promotion ──────────────────────────────────────
 
     it('a draft saved before the manifest arrived is promoted with the `requires` the save door computes', async () => {
 
@@ -72,6 +72,7 @@
     "BulkActionParamSchema (const)",
     "CHART_AGGREGATE_COMPARISON_SUFFIX (const)",
     "COLUMN_SUMMARY_AGGREGATION (const)",
+    "COMPILED_PAGE_KINDS (const)",
     "CalendarConfig (type)",
     "CalendarConfigSchema (const)",
     "ChartAggregate (type)",
@@ -482,6 +483,7 @@
     "checkDashboardWidgetStageOrder (function)",
     "checkGlobalFilterDateDefaultValue (function)",
     "checkListViewCalendarVisualization (function)",
+    "checkPageRequiresKind (function)",
     "checkPageSourceCompleteness (function)",
     "columnSummaryAlias (function)",
     "compileListViewGroupQuery (function)",
 
@@ -69,6 +69,7 @@
     "BulkActionParamSchema": "src/ui/bulk-action.zod.ts#BulkActionParamSchema (const)",
     "CHART_AGGREGATE_COMPARISON_SUFFIX": "src/ui/chart-aggregate.ts#CHART_AGGREGATE_COMPARISON_SUFFIX (const)",
     "COLUMN_SUMMARY_AGGREGATION": "src/ui/view-grouping-query.ts#COLUMN_SUMMARY_AGGREGATION (const)",
+    "COMPILED_PAGE_KINDS": "src/ui/page.zod.ts#COMPILED_PAGE_KINDS (const)",
     "CalendarConfig": "src/ui/view.zod.ts#CalendarConfig (type)",
     "CalendarConfigSchema": "src/ui/view.zod.ts#CalendarConfigSchema (const)",
     "ChartAggregate": "src/ui/chart.zod.ts#ChartAggregate (type)",
@@ -467,6 +468,7 @@
     "checkDashboardWidgetStageOrder": "src/ui/dashboard.zod.ts#checkDashboardWidgetStageOrder (function)",
     "checkGlobalFilterDateDefaultValue": "src/ui/dashboard.zod.ts#checkGlobalFilterDateDefaultValue (function)",
     "checkListViewCalendarVisualization": "src/ui/view.zod.ts#checkListViewCalendarVisualization (function)",
+    "checkPageRequiresKind": "src/ui/page.zod.ts#checkPageRequiresKind (function)",
     "checkPageSourceCompleteness": "src/ui/page.zod.ts#checkPageSourceCompleteness (function)",
     "columnSummaryAlias": "src/ui/view-grouping-query.ts#columnSummaryAlias (function)",
     "compileListViewGroupQuery": "src/ui/view-grouping-query.ts#compileListViewGroupQuery (function)",
 
@@ -8,11 +8,11 @@
     },
     "requires": {
       "status": "live",
-      "verifiedAt": "2026-10-02",
+      "verifiedAt": "2026-10-03",
       "evidenceScope": "in-repo",
-      "evidence": "SAVE: packages/metadata-protocol/src/runtime-authoring-gate.ts#findHtmlPageSourceGaps reads the authored list of a kind 'html' page and refuses one that disagrees with the namespaces its compiled source uses — 422 INVALID_METADATA under page-requires-disagrees-with-source, on an active save and on a draft's publish; packages/metadata-protocol/src/runtime-authoring-gate.ts#stampHtmlPageRequires stores the compiled list on save, and packages/metadata-protocol/src/protocol.ts#promoteDraftForPublish applies it again to the body a draft promotion writes. LOAD: packages/metadata-protocol/src/protocol.ts#reportPageRequiresAbsentAtLoad, called from boot hydration (loadMetaFromDb), reports a stored page whose list names a namespace no component in the manifest carries (packages/metadata-protocol/src/runtime-authoring-gate.ts#findPageRequiresAbsentFromManifest), page and plugin named; the page still loads and is served",
+      "evidence": "PARSE: packages/spec/src/ui/page.zod.ts#checkPageRequiresKind refuses the key on every kind but html / jsx (COMPILED_PAGE_KINDS) — a react, full or slotted page, a page that omits kind included — at requires, naming the key, the kind and the compiled kinds. SAVE: packages/metadata-protocol/src/runtime-authoring-gate.ts#findHtmlPageSourceGaps reads the authored list of a kind 'html' page and refuses one that disagrees with the namespaces its compiled source uses — 422 INVALID_METADATA under page-requires-disagrees-with-source, on an active save and on a draft's publish; packages/metadata-protocol/src/runtime-authoring-gate.ts#stampHtmlPageRequires stores the compiled list on save, and packages/metadata-protocol/src/protocol.ts#promoteDraftForPublish applies it again to the body a draft promotion writes. LOAD: packages/metadata-protocol/src/protocol.ts#reportPageRequiresAbsentAtLoad, called from boot hydration (loadMetaFromDb), reports a stored page whose list names a namespace no component in the manifest carries (packages/metadata-protocol/src/runtime-authoring-gate.ts#findPageRequiresAbsentFromManifest), page and plugin named; the page still loads and is served",
       "producer": "packages/cli/src/utils/sdui-manifest.ts#registerDeploymentSduiManifest — both moments compare the list against the deployment's SDUI component manifest, a second input: os serve (packages/cli/src/commands/serve.ts, which dev and start spawn) resolves it at boot and registers it under SDUI_MANIFEST_SERVICE, and packages/metadata-protocol/src/protocol.ts#resolveSduiManifest reads that key per publish and at load. A host that registers no manifest judges neither moment and prints one boot line saying so",
-      "note": "Plugin namespaces an html page's `source` uses (ADR-0080 §5), derived from the source at save. planned → live 2026-10-02 (#20871): refused at save since the save door landed (PR #20852, #20312 stages ① and ②), reported at load and re-stamped on draft promotion since #20870 (PR #21121). An authored list survives only when it agrees with the source; omitting it is the intended authoring. Boundaries: kind 'react' pages are not compiled at save (ADR-0081), so an authored list on one is judged only by the load report; a draft is stored as written and judged at its publish; rows already stored are reported, never rewritten."
+      "note": "Plugin namespaces an html page's `source` uses (ADR-0080 §5), derived from the source at save. planned → live 2026-10-02 (#20871): refused at save since the save door landed (PR #20852, #20312 stages ① and ②), reported at load and re-stamped on draft promotion since #20870 (PR #21121). An authored list survives only when it agrees with the source; omitting it is the intended authoring. Boundaries: the key exists only on kind 'html' / 'jsx' pages, the kinds compiled at save; on 'react' (not compiled at save, ADR-0081), 'full' and 'slotted' pages, a page with no kind being 'full', the parse refuses it since 2026-10-03 (#21459, ruling A), and the protocol-18 conversion page-requires-non-compiled-kind-removed strips it from stored rows and built artifacts at load; a draft is stored as written and judged at its publish; stored html rows are reported, never rewritten."
     },
     "name": {
       "status": "live",