@@ -0,0 +1,24 @@
+---
+'@objectstack/rest': patch
+'@objectstack/runtime': patch
+'@objectstack/metadata-protocol': patch
+'@objectstack/client': patch
+'@objectstack/spec': patch
+---
+
+feat(rest)!: the metadata list reads several items by name in one request (`?names=a,b,c`), and refuses a query parameter it does not read
+
+Clause-②: yes (narrowing) — `GET /api/v1/meta/:type` (and its environment-scoped twin, on both the REST server and the runtime dispatcher) declares its closed query-parameter set, `package`, `preview`, `object`, `include`, `id`, `names` and `locale`, and refuses any other name with `400 VALIDATION_ERROR`, where it ignored it and answered the whole list with `200`. The widening half: `?names=a,b,c` narrows every type's list but `package`'s to the items of those names, `@objectstack/client`'s `meta.getItems(type, { names })` sends it, and `@objectstack/rest` exports three new names, the list's query decision that both transports ask: `META_LIST_QUERY_PARAMS`, `metaListQueryRefusal` and `metaListNames`. Ruling 6580261740 assigns both halves to this one server change.
+Metadata-protocol: none
+
+<!-- adr-0087: not-required (no-migration-prescription) No key of any schema is added, removed, renamed or re-shaped: `GetMetaItemsRequestSchema.names` was already declared, and only its description loses the planned marker. What moves is the list route's answer to a query-string name it never read, and nothing at rest records that answer, so there is nothing for a migration to rewrite. -->
+
+**The batch by-names read.** `GET /api/v1/meta/:type?names=a,b,c` answers only the items of those names, among the items the list would answer without it, on every metadata type except `package`, whose items are keyed by id and carry no `name`: the `package` list refuses `?names=` with `400 VALIDATION_ERROR`. One comma-separated value, as the data routes spell `fields`; each name is trimmed and repeats count once. A name that matches no item is simply absent from the answer (no `404`). The names are handed to the store read (`GetMetaItemsRequest.names`), so `@objectstack/metadata-protocol`'s `getMetaItems` filters before it computes locks, governance and diagnostics, and the list's per-caller gate, object field mask and translation run on the named items only. A value that names no item (`?names=`, `?names=,`) is refused with `400 VALIDATION_ERROR` rather than read as every item; leave the key out to list every item. A repeated `?names=` is refused like the list's other single-valued parameters. Before, `?names=` was ignored, so a client that needed several objects paid one by-name request for each.
+
+**BREAKING** accept-set narrowing at the metadata list (`@objectstack/rest`, `@objectstack/runtime`): a query parameter the list does not read is refused instead of ignored.
+
+- **Before.** `GET /meta/object?name=account`, `?ids=a,b` or `?filter=x` answered `200` with every object, which reads the same as a filter that matched everything.
+- **Now.** A name outside `package`, `preview`, `object`, `include`, `id`, `names`, `locale` is refused with `400` and the nested `{ "error": { "code": "VALIDATION_ERROR", "message" } }` body; the message names the parameter and lists the supported ones, and nothing is read. A bracketed `?package[]=`, and `?id[]=` on the app list or `?object[]=` on the view list, keep their own located refusal; any other bracketed key (`?names[]=`) is refused as a name the list does not read.
+- **Who moves.** The Console and the client SDK send only declared names. A script that sends another name gets the 400.
+
+**The remedy.** Drop the parameter, or spell it as one of the supported names: `?names=a,b` for several items by name, `?id=APP` for one app, `?object=OBJECT` for one object's views, `?package=ID` for one package.
@@ -967,6 +967,17 @@ A type listing returns `{ type, items }` — the requested metadata `type` plus
 }
 ```
 
+To read several items of one type in a single request, name them:
+`GET /api/v1/meta/object?names=account,contact` answers only those items, among
+the ones the caller may see. The value is one comma-separated list; a name that
+matches no item is simply absent from `items`, and an empty value (`?names=`) is
+refused with `400 VALIDATION_ERROR`. `?names=` works on every type except
+`package`, whose items are keyed by id rather than name; the `package` list
+refuses it with `400 VALIDATION_ERROR`. The list reads a closed set of query
+parameters (`package`, `preview`, `object`, `include`, `id`, `names` and
+`locale`) and refuses any other name with `400 VALIDATION_ERROR` instead of
+ignoring it.
+
 ### Get Object Schema
 
 **Request:**
 
@@ -1517,7 +1517,7 @@ One changed key path of the pending draft, and the last write that changed it.
 | :--- | :--- | :--- | :--- |
 | **type** | `string` | ✅ | Metadata type name (e.g., "object", "plugin") |
 | **packageId** | `string` | optional | Optional package ID to filter items by |
-| **names** | `string[]` | optional | [PLANNED — not yet served] Item names to narrow the list to: only the named items of the type are answered, among those the list would answer without it. Sent over HTTP as one comma-separated value (`?names=a,b,c`). A name that matches no item is simply absent from the answer (no 404). An empty value is refused with 400 rather than read as every item; leave the key out to list every item. No list door reads it yet: until one does, a request carrying it is answered as if it were absent. |
+| **names** | `string[]` | optional | Item names to narrow the list to: only the named items of the type are answered, among those the list would answer without it. Served on every type except `package`, whose items are keyed by id; the `package` list refuses it with 400. Sent over HTTP as one comma-separated value (`?names=a,b,c`). A name that matches no item is simply absent from the answer (no 404). An empty value is refused with 400 rather than read as every item; leave the key out to list every item. |
 | **previewDrafts** | `boolean` | optional | Draft-visibility switch (ADR-0033 draft-overlay preview): when true, pending `state='draft'` rows are overlaid on the active list — draft wins on name collision, draft-only items appear, and each overlaid item is tagged `_draft: true` so UIs can badge the preview. Absent/false = published world only. Declaration ≠ authorization: this member only switches which rows are read, and ADR-0106 masking is unaffected — callers without draft-preview authorization are refused upstream (admin-gated), not by this schema. |
 
 
 
@@ -187,6 +187,28 @@ describe('ObjectStackClient', () => {
         expect(result.items).toHaveLength(2);
     });
 
+    it('[#29236] sends `names` as ONE comma-separated `?names=` value, on the unscoped and the environment surface', async () => {
+        const fetchMock = vi.fn().mockResolvedValue({
+            ok: true,
+            json: async () => ({ type: 'object', items: [{ name: 'customer' }] }),
+        });
+        const client = new ObjectStackClient({ baseUrl: 'http://localhost:3000', fetch: fetchMock });
+
+        await client.meta.getItems('object', { names: ['customer', 'order'] });
+        await client.meta.getItems('object', { packageId: 'com.acme', names: ['customer'] });
+        await client.environment('env_1').meta.getItems('object', { names: ['customer', 'order'] });
+        // An empty list is sent as the empty filter the server refuses, never dropped into "every item".
+        await client.meta.getItems('object', { names: [] });
+
+        const urls = fetchMock.mock.calls.map((c) => String(c[0]));
+        expect(urls).toEqual([
+            'http://localhost:3000/api/v1/meta/object?names=customer%2Corder',
+            'http://localhost:3000/api/v1/meta/object?package=com.acme&names=customer',
+            'http://localhost:3000/api/v1/environments/env_1/meta/object?names=customer%2Corder',
+            'http://localhost:3000/api/v1/meta/object?names=',
+        ]);
+    });
+
     it('should get metadata item by type and name', async () => {
         // The server's body is the spec-declared `GetMetaItemResponseSchema`
         // envelope — `{ type, name, item }`, with the metadata document under
 
@@ -1939,12 +1939,17 @@ export class ObjectStackClient {
     /**
      * Get all items of a specific metadata type
      * @param type - Metadata type name (e.g., 'object', 'plugin')
-     * @param options - Optional filters (e.g., packageId to scope by package)
+     * @param options - Optional filters: `packageId` scopes the list to one
+     *   package; `names` narrows it to the items of those names, in ONE request
+     *   (sent as `?names=a,b,c`). A name that matches no item is simply absent
+     *   from the answer. An empty `names` array is sent as an empty filter,
+     *   which the server refuses with `400`; leave `names` out to list every item.
      */
-    getItems: async (type: string, options?: { packageId?: string }): Promise<GetMetaItemsResponse> => {
+    getItems: async (type: string, options?: { packageId?: string; names?: readonly string[] }): Promise<GetMetaItemsResponse> => {
         const route = this.getRoute('metadata');
         const params = new URLSearchParams();
         if (options?.packageId) params.set('package', options.packageId);
+        if (options?.names !== undefined) params.set('names', options.names.join(','));
         const qs = params.toString();
         const url = `${this.baseUrl}${route}/${type}${qs ? `?${qs}` : ''}`;
         const res = await this.fetch(url);
@@ -8194,9 +8199,11 @@ export class ScopedEnvironmentClient {
       const res = await this.parent._fetch(this.metaUrl(''));
       return this.parent._unwrap<GetMetaTypesResponse>(res);
     },
-    getItems: async (type: string, options?: { packageId?: string }): Promise<GetMetaItemsResponse> => {
+    /** The unscoped surface's `getItems`, `names` included (one `?names=a,b,c` request). */
+    getItems: async (type: string, options?: { packageId?: string; names?: readonly string[] }): Promise<GetMetaItemsResponse> => {
       const params = new URLSearchParams();
       if (options?.packageId) params.set('package', options.packageId);
+      if (options?.names !== undefined) params.set('names', options.names.join(','));
       const qs = params.toString();
       const res = await this.parent._fetch(this.metaUrl(`/${type}${qs ? `?${qs}` : ''}`));
       return this.parent._unwrap<GetMetaItemsResponse>(res);
 
@@ -51,7 +51,7 @@ import { viewIdentityPatch } from './protocol-view-normalization.js';
 import { isServedOverrideRowOf } from './served-override.js';
 
 /** The body of `ObjectStackProtocolImplementation#getMetaItems`; the method's docblock there is its contract. */
-export async function getMetaItems(host: Pick<ProtocolHost, 'readFlattenedMetaItems'>, request: { type: string; packageId?: string; previewDrafts?: boolean }) {
+export async function getMetaItems(host: Pick<ProtocolHost, 'readFlattenedMetaItems'>, request: { type: string; packageId?: string; names?: readonly string[]; previewDrafts?: boolean }) {
     // #4432 — CANONICAL TYPE KEY. See {@link canonicalMetaType}. This one
     // is load-bearing twice over: the SchemaRegistry indexes code-authored
     // items under the SINGULAR type, and the overlay-hydration branch below
@@ -78,7 +78,7 @@ export async function getMetaItemsPerPackage(host: Pick<ProtocolHost, 'readFlatt
 }
 
 /** The body of `ObjectStackProtocolImplementation#readFlattenedMetaItems`; the method's docblock there is its contract. */
-export async function readFlattenedMetaItems(host: Pick<ProtocolHost, 'artifactLockLayerAt' | 'baseServesBundleMember' | 'convertStoredItem' | 'declinesStoredRow' | 'disabledActionsOf' | 'engine' | 'environmentId' | 'expandStoredViewContainers' | 'findEnvironmentRows' | 'flowRegistrationsOf' | 'foldObjectExtendersFromRegistry' | 'getServicesRegistry' | 'governServedObject' | 'hydrateOverlayIntoRegistry' | 'isStoredEntryOfDeclinedName' | 'isUnservedSealedOverlay' | 'isWritablePackage' | 'lookupArtifactItem' | 'namesWithOwnStoredRow' | 'readActiveOverlayRows' | 'rethrowUnlessMetadataStoreUnprovisioned' | 'shippedArtifactsOf' | 'shippingPackagesOf' | 'shipsBundleName' | 'storedOverlayEntries'>, request: { type: string; packageId?: string; previewDrafts?: boolean },
+export async function readFlattenedMetaItems(host: Pick<ProtocolHost, 'artifactLockLayerAt' | 'baseServesBundleMember' | 'convertStoredItem' | 'declinesStoredRow' | 'disabledActionsOf' | 'engine' | 'environmentId' | 'expandStoredViewContainers' | 'findEnvironmentRows' | 'flowRegistrationsOf' | 'foldObjectExtendersFromRegistry' | 'getServicesRegistry' | 'governServedObject' | 'hydrateOverlayIntoRegistry' | 'isStoredEntryOfDeclinedName' | 'isUnservedSealedOverlay' | 'isWritablePackage' | 'lookupArtifactItem' | 'namesWithOwnStoredRow' | 'readActiveOverlayRows' | 'rethrowUnlessMetadataStoreUnprovisioned' | 'shippedArtifactsOf' | 'shippingPackagesOf' | 'shipsBundleName' | 'storedOverlayEntries'>, request: { type: string; packageId?: string; names?: readonly string[]; previewDrafts?: boolean },
         audience: 'served' | 'execution',
         layer: 'effective' | 'per-package' = 'effective',) {
     const { packageId } = request;
@@ -690,6 +690,21 @@ export async function readFlattenedMetaItems(host: Pick<ProtocolHost, 'artifactL
         items = (items as any[]).filter((it) => !(it && typeof it === 'object' && unseated.has(it)));
     }
 
+    // [#29236, ruling 6580261740 letter A] `GetMetaItemsRequest.names` — the
+    // list door's `?names=a,b`, pushed down: only the items of those names,
+    // kept HERE, once every source is merged and before any step below, so the
+    // narrowing, the hiding, the lock selection, the governance and the
+    // serving decorations all run on the named items alone. Every step below
+    // judges an item by its own name and rows, so the named items are served
+    // exactly as the whole list would serve them. A name that matches nothing
+    // is simply absent. Absent, every item (the list as before); the door
+    // refuses an empty filter before it reads, so an empty one never names
+    // "every item" here either: it keeps none.
+    if (request.names !== undefined) {
+        const wanted = new Set(request.names);
+        items = (items as any[]).filter((it) => it && typeof it === 'object' && wanted.has((it as any).name));
+    }
+
     // [#28409, ADR-0146 D8 items 1–2, #28238's list half] THE ENV-WIDE
     // LIST JOINS THE ONE EFFECTIVE READ. Naming no package, a name exactly
     // one code package ships is listed once, as that package's item
 
@@ -0,0 +1,80 @@
+// Copyright (c) 2026 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * [#29236, ruling 6580261740 letter A] `getMetaItems({ type, names })` — the
+ * list door's `?names=a,b` pushed down to the store read
+ * (`GetMetaItemsRequestSchema.names`).
+ *
+ * The protocol keeps the items of those names once every source is merged,
+ * BEFORE the per-item work after the merge (the app nav contributions, the lock
+ * selection, the governance, the serving decorations), so that work runs on the
+ * named items alone. A name that matches nothing is simply absent.
+ *
+ * The engine is the shape `get-meta-items-package-writable.test.ts` drives: the
+ * registry surface the list read touches and a `find` that answers the overlay
+ * query with nothing.
+ */
+
+import { describe, it, expect } from 'vitest';
+import { ObjectStackProtocolImplementation } from './protocol.js';
+
+const APPS = ['crm', 'helpdesk', 'payroll'].map((name) => ({ name, label: name.toUpperCase(), navigation: [] }));
+const OBJECTS = ['account', 'contact', 'lead'].map((name) => ({ name, label: name, fields: { name: { type: 'text' } } }));
+
+function make() {
+    const contributedTo: string[] = [];
+    const engine: any = {
+        manifests: new Map(),
+        find: async () => [],
+        registry: {
+            listItems: (type: string) => structuredClone(type === 'app' ? APPS : type === 'object' ? OBJECTS : []),
+            getPackage: () => undefined,
+            getItem: () => undefined,
+            getObject: () => undefined,
+            getArtifactItem: () => undefined,
+            isPackageDisabled: () => false,
+            applyNavContributions: (app: any) => {
+                contributedTo.push(app?.name);
+                return app;
+            },
+        },
+    };
+    const protocol = new ObjectStackProtocolImplementation(engine, () => new Map());
+    return { protocol, contributedTo };
+}
+
+const namesOf = (res: any): string[] => (res.items as any[]).map((it) => it.name);
+
+describe('getMetaItems — `names` narrows the served list (#29236)', () => {
+    it('keeps only the named items, on `object` and on `app`', async () => {
+        const { protocol } = make();
+        expect(namesOf(await protocol.getMetaItems({ type: 'object', names: ['lead', 'account'] }))).toEqual(['account', 'lead']);
+        expect(namesOf(await protocol.getMetaItems({ type: 'app', names: ['helpdesk'] }))).toEqual(['helpdesk']);
+    });
+
+    it('narrows BEFORE the per-item work after the merge: only the named apps get their nav contributions', async () => {
+        const { protocol, contributedTo } = make();
+        await protocol.getMetaItems({ type: 'app', names: ['payroll', 'crm'] });
+        expect(contributedTo.sort()).toEqual(['crm', 'payroll']);
+    });
+
+    it('a name that matches nothing is simply absent', async () => {
+        const { protocol } = make();
+        expect(namesOf(await protocol.getMetaItems({ type: 'object', names: ['account', 'nope'] }))).toEqual(['account']);
+        expect(namesOf(await protocol.getMetaItems({ type: 'object', names: ['nope'] }))).toEqual([]);
+    });
+
+    it('serves each named item exactly as the whole list serves it', async () => {
+        const { protocol } = make();
+        const whole = await protocol.getMetaItems({ type: 'object' });
+        const named = await protocol.getMetaItems({ type: 'object', names: ['contact'] });
+        expect(named.items).toEqual((whole.items as any[]).filter((it) => it.name === 'contact'));
+    });
+
+    it('control: absent `names` lists every item, and every app gets its contributions', async () => {
+        const { protocol, contributedTo } = make();
+        expect(namesOf(await protocol.getMetaItems({ type: 'object' }))).toEqual(['account', 'contact', 'lead']);
+        await protocol.getMetaItems({ type: 'app' });
+        expect(contributedTo.sort()).toEqual(['crm', 'helpdesk', 'payroll']);
+    });
+});
@@ -3814,7 +3814,13 @@ export class ObjectStackProtocolImplementation implements
         return throwMetadataServiceUnavailable(errors);
     }
 
-    async getMetaItems(request: { type: string; packageId?: string; previewDrafts?: boolean }) {
+    /**
+     * The served list of one metadata type. [#29236] `names` narrows it to the
+     * items of those names (`GetMetaItemsRequestSchema.names`): a name that
+     * matches nothing is absent, and the narrowing runs before the serving
+     * decorations, so they are computed for the named items only.
+     */
+    async getMetaItems(request: { type: string; packageId?: string; names?: readonly string[]; previewDrafts?: boolean }) {
         // [#25467 E1] The body moved to `protocol-meta-list-reads.ts`; it reaches this class through `protocol-host.ts`.
         return getMetaItems(protocolHost(this), request);
     }
@@ -3988,7 +3994,7 @@ export class ObjectStackProtocolImplementation implements
      * `request` arrives already folded by the calling face (#4432).
      */
     private async readFlattenedMetaItems(
-        request: { type: string; packageId?: string; previewDrafts?: boolean },
+        request: { type: string; packageId?: string; names?: readonly string[]; previewDrafts?: boolean },
         audience: 'served' | 'execution',
         layer: 'effective' | 'per-package' = 'effective',
     ) {