@@ -0,0 +1,38 @@
+---
+"@objectstack/metadata": minor
+---
+
+feat(metadata): the artifact door registers stack-declared `capabilities` (#12892 step 1)
+
+`ARTIFACT_FIELD_TO_TYPE` — the map that decides which collections of a compiled
+artifact reach `MetadataManager` — now carries `capabilities: 'capability'`.
+This is step 1 of the maintainer's 2026-08-29 ruling on #12892 (option 1: *the
+door owns the registration route* for the five artifact security collections).
+
+**FROM.** `capabilities` is an authorable top-level stack collection (ADR-0066
+D1), but the door did not map it while `AppPlugin`'s ADR-0057 `SECURITY_FIELDS`
+block did — making that block the collection's **sole registrar on an artifact
+boot**, and it registers the raw bundle bytes with no strict parse, no schema
+default and no ADR-0010 provenance. On a `bootstrap: 'artifact-only'` runtime
+where `AppPlugin` does not run, a package's declared capabilities reached no
+registry at all: `GET /meta/capability` answered **empty**, and
+`bootstrapDeclaredCapabilities` seeded **no `sys_capability` row** for them.
+
+**TO.** The door registers them like every other mapped collection: strict
+parse, schema defaults, ADR-0010 provenance. Measured on a real artifact-only
+kernel boot with no `AppPlugin`, over a package declaring
+`{ name: 'crm.export', label: 'Export CRM data' }`:
+
+- `GET /meta/capability` went from `[]` to one item carrying `scope:'platform'`
+  (the `CapabilitySchema` default) plus `_packageId` / `_packageVersion` /
+  `_provenance`;
+- `sys_capability` went from 9 rows (platform-curated only) to 10 — the
+  declaration now materializes with `managed_by:'package'` and its `package_id`.
+
+**What this does NOT change, deliberately.** On the ordinary artifact boot
+`AppPlugin` still registers `capabilities` and still runs last, so its unparsed
+copy still wins the registry — measured byte-identical before and after this
+change. Two registrars on one route is the interim state the ruling explicitly
+permits while step 2 (that block stops registering the five on the **artifact**
+path, after a census of the non-artifact boots that depend on it) lands. No
+authoring surface moves, and no artifact that parses today stops parsing.
@@ -0,0 +1,107 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * The artifact door registers stack-declared `capabilities` (#12892 step 1).
+ *
+ * `capabilities` is an authorable top-level stack collection (ADR-0066 D1).
+ * Until this entry landed, `ARTIFACT_FIELD_TO_TYPE` did not map it while
+ * `AppPlugin`'s ADR-0057 `SECURITY_FIELDS` block did — so on an artifact boot
+ * that block was the collection's SOLE registrar, and it registers the raw
+ * bundle bytes: no strict parse, no schema default, no ADR-0010 provenance.
+ * That asymmetry is what `scripts/check-stack-collection-maps.mjs` waived as
+ * "DRIFT with a real, bounded consequence"; the maintainer's ruling on #12892
+ * (2026-08-29, option 1 — "the door owns the registration route") closes it,
+ * and this file is the door half.
+ *
+ * Driven through the real `_parseAndRegisterArtifact`, so what is asserted is
+ * what a sealed (`bootstrap: 'artifact-only'`) runtime actually serves under
+ * `GET /meta/capability`, not what the map literal says.
+ *
+ * ⚠️ This does NOT make the door the only registrar: `AppPlugin` still
+ * registers `capabilities`, and on a real artifact boot it runs LAST, so its
+ * unparsed copy still wins the registry. Measured on a real artifact-only
+ * kernel boot for the PR, and that is precisely why step 2 of the ruling
+ * exists. What step 1 changes on its own is the boot where `AppPlugin` does
+ * not run: there, `GET /meta/capability` answered EMPTY and now answers the
+ * parsed, defaulted, provenance-stamped item.
+ */
+
+import { describe, it, expect, vi } from 'vitest';
+import { MetadataPlugin } from './plugin.js';
+
+function fakeCtx() {
+    return {
+        logger: { info: vi.fn(), warn: vi.fn(), error: vi.fn(), debug: vi.fn() },
+        registerService: vi.fn(),
+        getService: vi.fn(() => undefined),
+        trigger: vi.fn(),
+    } as any;
+}
+
+function newPlugin(): any {
+    return new MetadataPlugin({ watch: false, config: { bootstrap: 'lazy' } });
+}
+
+/** The authored bytes — deliberately the MINIMUM a capability may declare. */
+function artifact(overrides: Record<string, unknown> = {}): any {
+    return {
+        manifest: {
+            id: 'com.test.cap-door',
+            name: 'Capability Door Probe',
+            type: 'app',
+            version: '3.4.5',
+        },
+        capabilities: [{ name: 'crm.export', label: 'Export CRM data' }],
+        ...overrides,
+    };
+}
+
+describe('artifact door — stack-declared capabilities (#12892 step 1, ADR-0066 D1)', () => {
+    it('registers a declared capability under the `capability` metadata type', async () => {
+        const plugin = newPlugin();
+        await plugin._parseAndRegisterArtifact(fakeCtx(), artifact(), 'cap-door-probe');
+
+        const registered = await plugin.manager.get('capability', 'crm.export');
+        expect(registered, 'the door must register the declared capability').toBeDefined();
+        expect(await plugin.manager.list('capability')).toHaveLength(1);
+    });
+
+    it('the registered copy carries what only the door can add: the schema default and the ADR-0010 provenance envelope', async () => {
+        const plugin = newPlugin();
+        await plugin._parseAndRegisterArtifact(fakeCtx(), artifact(), 'cap-door-probe');
+        const registered: any = await plugin.manager.get('capability', 'crm.export');
+
+        // The authored bytes carry NEITHER of these — this is the whole
+        // difference between the door's copy and the bundle reader's, and
+        // asserting the authored keys alone would pass on either.
+        expect(registered.scope, 'CapabilitySchema default (authored bytes omit it)').toBe('platform');
+        expect(registered._packageId).toBe('com.test.cap-door');
+        expect(registered._packageVersion).toBe('3.4.5');
+        expect(registered._provenance).toBe('package');
+
+        // …and the authored fields survive unchanged.
+        expect(registered).toMatchObject({ name: 'crm.export', label: 'Export CRM data' });
+    });
+
+    it('NEGATIVE control — an artifact declaring no capabilities registers none', async () => {
+        // Guards the two cases above against passing on a constant: the
+        // assertion has to track the input, not the map.
+        const plugin = newPlugin();
+        const bare = artifact();
+        delete bare.capabilities;
+        await plugin._parseAndRegisterArtifact(fakeCtx(), bare, 'cap-door-probe-empty');
+        expect(await plugin.manager.list('capability')).toEqual([]);
+    });
+
+    it('the strict parse still governs the item — a malformed capability reaches no registry', async () => {
+        // #12894 measured that the map entry adds NO validation: the door
+        // strict-parses the whole definition BEFORE consulting the map, so a
+        // malformed capability was already refused and still is. Pinned here so
+        // "the door registers capabilities" is never read as "the door
+        // registers whatever the bytes say".
+        const plugin = newPlugin();
+        const bad = artifact({ capabilities: [{ name: 'crm.export', label: 'Export CRM data', nope: 1 }] });
+        await plugin._parseAndRegisterArtifact(fakeCtx(), bad, 'cap-door-probe-bad').catch(() => undefined);
+        expect(await plugin.manager.list('capability')).toEqual([]);
+    });
+});
@@ -89,6 +89,26 @@ const ARTIFACT_FIELD_TO_TYPE: Record<string, string> = {
     // positions from artifact ingestion.
     positions: 'position',
     permissions: 'permission',
+    // [ADR-0066 D1] `capabilities` reaches the door at #12892 step 1, the
+    // maintainer's `option 1` ruling ("the door owns the registration
+    // route" for the five artifact security collections). Until #12894
+    // measured it, `AppPlugin`'s `SECURITY_FIELDS` block
+    // (packages/runtime/src/app-plugin.ts) was this collection's SOLE
+    // registrar on an artifact boot — the one security collection the door
+    // could not reach — so a declared capability was registered from bytes
+    // nothing strict-parses, with no schema default and no ADR-0010
+    // provenance. Measured on the two-reader harness, the door's copy adds
+    // exactly four keys the raw copy lacks: `scope` (the schema default)
+    // and `_packageId` / `_packageVersion` / `_provenance`.
+    //
+    // ⚠️ This entry makes the door a SECOND writer, not yet the only one:
+    // `AppPlugin` still registers `capabilities`, and it runs last, so the
+    // raw copy still wins a real artifact boot. Step 2 of the ruling (that
+    // block stops registering these five on the artifact path, after a
+    // census of the non-artifact boot paths) is what makes this the only
+    // copy. Until then the divergence is the interim reality the ruling
+    // explicitly permits, and #12878's pins are what keep it visible.
+    capabilities: 'capability',
     sharingRules: 'sharing_rule',
     // `policies: 'policy'` removed at #12894: the stack schema is a
     // `strictObject` that declares no top-level `policies` key, so a
 
@@ -251,7 +251,12 @@ describe('#12844 — the artifact boot\'s two readers register the same bytes',
         const shared = [...bundle.keys()].filter((k) => door.has(k)).sort();
 
         // Guard the comparison against being vacuously green.
+        // `capability:crm.export` joined this list at #12892 step 1: the door's
+        // `ARTIFACT_FIELD_TO_TYPE` now maps `capabilities`, so that collection
+        // has TWO readers here for the first time. Measured, not predicted —
+        // and the only edit this list took.
         expect(shared).toEqual([
+            'capability:crm.export',
             'permission:support_agent',
             'position:sales_rep',
             'sharing_rule:share_open_deals',
@@ -336,23 +341,79 @@ describe('#12844 — the artifact boot\'s two readers register the same bytes',
         expect(typeof (bundleFirst.get('sharing_rule:share_open_deals') as any).condition).toBe('object');
     });
 
-    // ── The two collections that have no second copy to diverge ──────────
+    // ── `capabilities`: TWO readers since #12892 step 1 · `policies`: none ────
     //
-    // Recorded as measurements, not omissions: the card names five security
-    // collections, and two of them never travel this path in a way that could
-    // produce two copies. Neither is a reason to skip the collection — it is
-    // what "covered" means for them.
+    // Recorded as measurements, not omissions. `policies` still never travels
+    // this path in a way that could produce two copies. `capabilities` did not
+    // either until #12892 step 1 put it in the door's map — the case below used
+    // to assert that ABSENCE, and an assertion of an absence stops being a
+    // guard the moment the absence is deliberately removed. It is REWRITTEN
+    // here rather than relaxed, and rewritten UPWARD: it now pins the interim
+    // divergence key by key.
 
-    it('capabilities: only ONE reader exists — the door never registers them', async () => {
+    /**
+     * ⚠️ THIS CASE EXISTS TO GO RED WHEN STEP 2 LANDS. That is its job, not a
+     * regression.
+     *
+     * The maintainer's 2026-08-29 ruling on #12892 is two ordered steps:
+     *
+     *   step 1 (landed) — the door's `ARTIFACT_FIELD_TO_TYPE` maps
+     *     `capabilities`, so BOTH readers now register the collection. Two
+     *     writers on one route is the INTERIM state the ruling permits, and
+     *     what this case measures is exactly how the two copies differ while
+     *     it lasts.
+     *   step 2 (not landed) — `AppPlugin`'s ADR-0057 `SECURITY_FIELDS` block
+     *     stops registering these five on the ARTIFACT path (it must keep
+     *     registering on non-artifact boots), leaving the door's parsed,
+     *     defaulted, provenance-stamped copy as the only one.
+     *
+     * The day step 2 lands, `readerBundle()` stops producing
+     * `capability:crm.export`, and EVERY assertion below goes red — the
+     * membership pin, the key-by-key divergence set, and the four named-key
+     * pins alike. Whoever lands step 2 rewrites this case to assert the single
+     * remaining copy; ⛔ never by deleting, skipping or weakening it, which is
+     * the one repair that would let the route silently keep two writers.
+     *
+     * Two seams, two answers, both real — do not read one as refuting the other:
+     * HERE the two copies differ on FOUR keys, because `readerBundle()` drives
+     * `AppPlugin` against a bare `registerInMemory` capture. On a full kernel
+     * boot the ObjectQL SchemaRegistry stamps `_packageId` / `_provenance` onto
+     * that same object during package install, so the end-to-end divergence
+     * narrows to the TWO the registry cannot supply: `scope` (the schema
+     * default) and `_packageVersion`. Those two are the seam-invariant core and
+     * are pinned by name below in addition to the set.
+     */
+    it('capabilities: BOTH readers register them since #12892 step 1, and the two copies diverge on exactly four keys', async () => {
         const door = collapse(await readerDoor());
         const bundle = collapse(await readerBundle());
-        // `capabilities` is an authorable stack collection (ADR-0066 D1) that
-        // `ARTIFACT_FIELD_TO_TYPE` (`packages/metadata/src/plugin.ts`) does not
-        // map, so the artifact door registers nothing under `capability` and
-        // AppPlugin is the sole registrar. No divergence is constructible.
-        expect(bundle.get('capability:crm.export')).toBeDefined();
-        expect(door.has('capability:crm.export')).toBe(false);
-        expect([...door.keys()].filter((k) => k.startsWith('capability:'))).toEqual([]);
+
+        // Membership: two readers, not one. (Before step 1 the door registered
+        // nothing under `capability` and this collection had a single writer.)
+        expect(bundle.get('capability:crm.export'), 'AppPlugin must still register the capability').toBeDefined();
+        expect(door.get('capability:crm.export'), 'the door must now register it too').toBeDefined();
+        expect([...door.keys()].filter((k) => k.startsWith('capability:'))).toEqual(['capability:crm.export']);
+
+        // The divergence, key by key — the whole set, so a key that appears or
+        // disappears fails here rather than passing under a looser shape.
+        expect(diffPaths(door.get('capability:crm.export'), bundle.get('capability:crm.export')).sort())
+            .toEqual(['_packageId', '_packageVersion', '_provenance', 'scope']);
+
+        // …and the two that survive every seam, pinned BY NAME with the value
+        // each side actually carries. `scope` is the `CapabilitySchema`
+        // default, `_packageVersion` half of the ADR-0010 envelope; the authored
+        // bytes declare neither, so only the copy that met the schema has them.
+        const doorCopy = door.get('capability:crm.export') as any;
+        const bundleCopy = bundle.get('capability:crm.export') as any;
+        expect(doorCopy.scope).toBe('platform');
+        expect(bundleCopy.scope).toBeUndefined();
+        expect(doorCopy._packageVersion).toBe('1.0.0');
+        expect(bundleCopy._packageVersion).toBeUndefined();
+
+        // The authored fields agree — "they differ" must not be satisfiable by
+        // the two copies being different documents altogether.
+        for (const copy of [doorCopy, bundleCopy]) {
+            expect(copy).toMatchObject({ name: 'crm.export', label: 'Export CRM data' });
+        }
     });
 
     it('policies: not an authorable stack collection at all — neither reader can see one', async () => {
 
@@ -592,15 +592,21 @@ const SITES = [
       },
       {
         direction: 'missing',
-        keys: ['datasets', 'jobs', 'datasources', 'translations', 'capabilities'],
+        keys: ['datasets', 'jobs', 'datasources', 'translations'],
         reason:
-          'DRIFT with a real, bounded consequence — #6242 row 4(b). Four of the five are consumed '
+          'DRIFT with a real, bounded consequence — #6242 row 4(b). All four are consumed '
           + 'functionally by AppPlugin straight off the bundle, so boot is not broken; what they never do is '
           + 'register as METADATA ITEMS, so under `bootstrap: \'artifact-only\'` (edge / serverless / '
           + 'immutable image) `GET /meta/job`, `/meta/translation`, `/meta/datasource` and `/meta/dataset` '
           + 'answer empty for a package that ships them. Adding them changes what a sealed runtime serves '
           + 'and must be measured on a real artifact-only boot first — the filing card says so, and this '
-          + 'gate does not smuggle it in.',
+          + 'gate does not smuggle it in. `capabilities` was the FIFTH key on this row and left it at '
+          + '#12892 step 1 (maintainer ruling, option 1: the door owns the registration route for the five '
+          + 'security collections). It was never the same fact as the other four: AppPlugin registers it as '
+          + 'a METADATA ITEM through `registerInMemory`, so `GET /meta/capability` was already non-empty on '
+          + 'an artifact-only boot — what was missing from that answer was the strict-parsed shape, the '
+          + '`scope` default and the ADR-0010 provenance stamp. Driven on a real artifact-only boot before '
+          + 'the entry landed, per the sentence above.',
       },
       {
         direction: 'missing',
@@ -677,9 +683,12 @@ const SITES = [
           + 'never runs; every other collection reaches the registry through the door or its own seam. '
           + 'Recorded as one row rather than left implicit so that a NEW security collection has to be '
           + 'considered here once — which is the direction this site was actually wrong in: `capabilities` '
-          + 'is registered here and NOT by the door, making this block that collection\'s sole registrar on '
-          + 'an artifact boot (#12894 half 2, carried to #12892 for the ownership decision — measured, '
-          + 'deliberately not changed here).',
+          + 'was registered here and NOT by the door, making this block that collection\'s sole registrar '
+          + 'on an artifact boot (#12894 half 2, carried to #12892 for the ownership decision). The door '
+          + 'reaches it as of #12892 step 1, so this block is no longer that collection\'s sole registrar — '
+          + 'it is the SECOND one, on the same boot path, which is the interim state the ruling permits '
+          + 'while step 2 (this block stops registering the five on the ARTIFACT path only, after a census '
+          + 'of the non-artifact boots that depend on it) lands.',
       },
     ],
   },