diff --git a/.changeset/ai-agents-envelope-declaration.md b/.changeset/ai-agents-envelope-declaration.md
new file mode 100644
index 0000000000..42d4a80bc2
--- /dev/null
+++ b/.changeset/ai-agents-envelope-declaration.md
@@ -0,0 +1,4 @@
+---
+---
+
+test(spec,client,runtime): relocate `AiAgentsResponseSchema` onto the `data` payload it now describes, and pin `GET /ai/agents` against its declaration (#4053). Both producers of the route — the framework's degraded fallback (#4124) and cloud's `service-ai` (cloud#929) — converted onto the declared envelope; this closes out the declaration half and corrects four comments that still described the migration as in flight. Comments, a doc-block and one new test file; releases nothing.
diff --git a/packages/client/src/ai-agents-envelope.test.ts b/packages/client/src/ai-agents-envelope.test.ts
index f1ee0ef76e..f5b7e1d5d9 100644
--- a/packages/client/src/ai-agents-envelope.test.ts
+++ b/packages/client/src/ai-agents-envelope.test.ts
@@ -4,11 +4,13 @@
  * `client.ai.agents.list()` against both shapes of `GET /api/v1/ai/agents` (#4053).
  *
  * This route has two producers — the framework dispatcher's degraded fallback when
- * no AI service is registered, and cloud's `service-ai` — and it is mid-migration
- * onto the declared envelope. The framework side converted first; cloud's has not
- * yet, so both shapes are live in the fleet and the SDK has to read either.
+ * no AI service is registered, and cloud's `service-ai`. Both answer in the declared
+ * envelope now: the framework side converted first (#4124) and cloud followed on its
+ * own schedule (cloud#929). The unenveloped shape is still read here because an SDK
+ * outlives the server it is pointed at — a current client talking to a deployment
+ * from before the conversion is ordinary, not hypothetical.
  *
- * That is only true because the conversion RELOCATES the declared payload under
+ * That independence was only possible because the conversion RELOCATES the payload under
  * `data` (`data: { agents }`) rather than flattening it to the bare array
  * (`data: [...]`). The distinction is the whole reason this file exists:
  *
@@ -46,14 +48,14 @@ const ASK = { name: 'ask', label: 'Ask', role: 'assistant' };
 const BUILD = { name: 'build', label: 'Build', role: 'assistant' };
 
 describe('client.ai.agents.list — both producers', () => {
-    it('reads the UNENVELOPED body (cloud service-ai, pre-#4053)', async () => {
+    it('reads the UNENVELOPED body — a pre-#4053 server this client still has to talk to', async () => {
         const { client, fetchMock } = clientAnswering({ agents: [ASK, BUILD] });
         const agents = await client.ai.agents.list();
         expect(String(fetchMock.mock.calls[0][0])).toBe('http://localhost:3000/api/v1/ai/agents');
         expect(agents.map((a: any) => a.name)).toEqual(['ask', 'build']);
     });
 
-    it('reads the ENVELOPED body with `data: { agents }` (the framework fallback, #4053)', async () => {
+    it('reads the ENVELOPED body with `data: { agents }` — what both producers serve (#4053)', async () => {
         const { client } = clientAnswering({ success: true, data: { agents: [ASK, BUILD] } });
         const agents = await client.ai.agents.list();
         expect(agents.map((a: any) => a.name)).toEqual(['ask', 'build']);
diff --git a/packages/client/src/index.ts b/packages/client/src/index.ts
index 6cd168540c..29b139e26a 100644
--- a/packages/client/src/index.ts
+++ b/packages/client/src/index.ts
@@ -3798,6 +3798,16 @@ export class ObjectStackClient {
        * Agents the CALLER may chat with — the route filters by the caller's
        * permissions (ADR-0049), so an empty list is a legitimate answer for a
        * seat-less user rather than an error to retry.
+       *
+       * The `.agents` read below survived #4053 unchanged, and that is the
+       * conclusion rather than an oversight. `AiAgentsResponseSchema` moved
+       * under the envelope's `data` as a RELOCATION (#3843's precedent), so
+       * `unwrapResponse` hands back `{ agents }` from an enveloped producer and
+       * the same object from a pre-conversion one. Had the route flattened to
+       * `data: [...]` (#3983's precedent) this line would read `undefined` and
+       * answer `[]` — an empty catalog, which is what the console reads as "this
+       * caller has no AI", so the regression would have been invisible.
+       * `ai-agents-envelope.test.ts` pins both readings.
        */
       list: async (): Promise<AiAgentSummary[]> => {
         const route = this.getRoute('ai');
diff --git a/packages/runtime/src/domain-handler-registry.test.ts b/packages/runtime/src/domain-handler-registry.test.ts
index 47120dcd17..c8b996744b 100644
--- a/packages/runtime/src/domain-handler-registry.test.ts
+++ b/packages/runtime/src/domain-handler-registry.test.ts
@@ -698,9 +698,9 @@ describe('HttpDispatcher extracted domains (PR-7: auth/ai)', () => {
         // #4053: in the declared envelope now, with `AiAgentsResponseSchema`'s
         // `{ agents }` RELOCATED under `data` rather than flattened to the bare
         // array. `unwrapResponse` returns `data`, so `client.ai.agents.list()`
-        // reads `.agents` off it and keeps working against cloud's still-
-        // unenveloped `service-ai` too — which is what lets the two surfaces
-        // convert independently instead of in lockstep.
+        // reads `.agents` off it — which is what let this surface convert on its
+        // own and cloud's `service-ai`, the route's other producer, follow
+        // independently instead of in lockstep. Both answer this now (cloud#929).
         expect(envelopeViolations(result.response?.body), JSON.stringify(result.response?.body)).toEqual([]);
         expect(result.response?.body?.data?.agents).toEqual([]);
         expect(result.response?.body?.agents).toBeUndefined();
diff --git a/packages/runtime/src/domains/ai.ts b/packages/runtime/src/domains/ai.ts
index d7b2f566d4..1d2f6b15e3 100644
--- a/packages/runtime/src/domains/ai.ts
+++ b/packages/runtime/src/domains/ai.ts
@@ -57,9 +57,10 @@ export async function handleAIRequest(deps: DomainHandlerDeps, subPath: string,
         // payload under `data`, the way `SettingsNamespacePayload` moved in #3843,
         // not a flatten to the bare array. That distinction is load-bearing here:
         // `unwrapResponse` returns `data`, so `client.ai.agents.list()` reads
-        // `.agents` off it and keeps working, and it keeps working against cloud's
-        // `service-ai` too while that surface still answers unenveloped. Flattening
-        // to `data: []` would have made `.agents` `undefined` — an empty catalog,
+        // `.agents` off it. It is also what let this side convert first and cloud's
+        // `service-ai` — the route's OTHER producer — follow independently rather
+        // than in lockstep; both answer this shape now (cloud#929). Flattening to
+        // `data: []` would have made `.agents` `undefined` — an empty catalog,
         // which `useAiSurfaceEnabled` turns into "hide the entire AI surface", and
         // which is indistinguishable from the legitimate seat-less/CE state.
         if (method === 'GET' && subPath === '/ai/agents') {
diff --git a/packages/runtime/src/http-dispatcher.test.ts b/packages/runtime/src/http-dispatcher.test.ts
index 3ba4fec20a..ecd5f2fda5 100644
--- a/packages/runtime/src/http-dispatcher.test.ts
+++ b/packages/runtime/src/http-dispatcher.test.ts
@@ -2785,7 +2785,8 @@ describe('HttpDispatcher', () => {
             // it just travels under `data` now. `AiAgentsResponseSchema`'s
             // `{ agents }` is RELOCATED, not flattened to the bare array, so
             // `client.ai.agents.list()` still reads `.agents` off what
-            // `unwrapResponse` returns.
+            // `unwrapResponse` returns. Cloud's `service-ai` — the route's other
+            // producer — answers the same shape (cloud#929).
             expect(agents.response?.body).toEqual({ success: true, data: { agents: [] }, meta: undefined });
             expect(agents.response?.body?.agents).toBeUndefined();
         });
diff --git a/packages/spec/src/api/ai-agents-envelope.test.ts b/packages/spec/src/api/ai-agents-envelope.test.ts
new file mode 100644
index 0000000000..062710e857
--- /dev/null
+++ b/packages/spec/src/api/ai-agents-envelope.test.ts
@@ -0,0 +1,119 @@
+// Copyright (c) 2025 ObjectStack. Licensed under the Apache-2.0 license.
+
+/**
+ * `GET /api/v1/ai/agents` — the declaration tied to the wire (#4053).
+ *
+ * The route has TWO producers in two repos: the framework dispatcher's degraded
+ * fallback when no AI service is registered (`runtime/src/domains/ai.ts`, the
+ * open-source default — `service-ai` is Cloud/EE) and cloud's `service-ai`
+ * `buildAgentRoutes`. Both now answer in the declared envelope, with
+ * `AiAgentsResponseSchema` RELOCATED under `data` rather than flattened to the
+ * bare array (framework#4124, cloud#929).
+ *
+ * Each producer pins its own body in its own repo. Neither repo can pin the
+ * OTHER one, and `scripts/check-route-envelope.mjs` reaches neither — it scans
+ * route modules that write via `res.json(...)`, while the dispatcher domains
+ * return `{ status, body }` for a central sender (#4049) and cloud is outside
+ * the framework guard entirely. What both producers DO share is this package,
+ * which is where the payload is declared. So the agreement is pinned here, once,
+ * against the declaration itself.
+ *
+ * Why bother, when nothing is broken today: the failure this route has is
+ * invisible. `useAiSurfaceEnabled` gates the ENTIRE AI surface on
+ * `agents.length > 0`, deliberately — the route is access-filtered per caller,
+ * making it the only signal that is both edition- and user-aware (ADR-0068). So
+ * an empty catalog is a CORRECT answer:
+ *
+ *   seat-less user                    → AI surface hidden  (correct)
+ *   Community Edition, no service-ai  → AI surface hidden  (correct)
+ *   a producer flattening `data`      → AI surface hidden  (the bug)
+ *
+ * No error, no 403, no failed request, no log. There is no downstream signal that
+ * would catch a producer drifting, which is why the shape is asserted rather than
+ * described.
+ */
+
+import { describe, expect, it } from 'vitest';
+import { envelopeViolations } from './contract.zod';
+import { AiAgentsResponseSchema } from './protocol.zod';
+
+const ASK = {
+  name: 'ask', label: 'Ask', role: 'assistant',
+  capabilities: { authoring: false, canvas: false, debug: false, resume: false },
+};
+const BUILD = {
+  name: 'build', label: 'Build', role: 'authoring',
+  capabilities: { authoring: true, canvas: true, debug: true, resume: true },
+};
+
+/** Both halves of the contract: a conformant envelope AND a conformant `data`. */
+function servesTheDeclaredShape(body: unknown): boolean {
+  if (envelopeViolations(body).length > 0) return false;
+  return AiAgentsResponseSchema.safeParse((body as { data?: unknown }).data).success;
+}
+
+describe('GET /ai/agents — the body both producers now answer with', () => {
+  it('the populated catalog: envelope-conformant, and `data` IS the declared payload', () => {
+    const body = { success: true, data: { agents: [ASK, BUILD] } };
+    expect(envelopeViolations(body)).toEqual([]);
+    expect(AiAgentsResponseSchema.safeParse(body.data).success).toBe(true);
+  });
+
+  it('the empty catalog — the framework fallback, and a seat-less caller', () => {
+    // Two different reasons for the same body, both correct. The fallback emits
+    // exactly this when no AI service is registered; `service-ai` emits it for a
+    // caller whose permission set reaches no agent (ADR-0049).
+    const body = { success: true, data: { agents: [] } };
+    expect(envelopeViolations(body)).toEqual([]);
+    expect(AiAgentsResponseSchema.safeParse(body.data).success).toBe(true);
+  });
+
+  it('`meta` beside the payload is fine — `deps.success` builds it', () => {
+    expect(servesTheDeclaredShape({ success: true, data: { agents: [] }, meta: undefined })).toBe(true);
+    expect(servesTheDeclaredShape({ success: true, data: { agents: [] }, meta: { timestamp: 't' } })).toBe(true);
+  });
+});
+
+describe('GET /ai/agents — the shapes a producer must NOT drift back into', () => {
+  it('the FLATTENED conversion — the one that empties the agent list', () => {
+    // #3983 set the precedent that `data` carries the payload directly, and
+    // following it here would look consistent. It is the wrong reading:
+    // `AiAgentsResponseSchema` is a DECLARED payload schema, where share-links'
+    // `{ links }` was an ad-hoc wrapper with none — so this is the #3843
+    // relocation, not a reshape.
+    //
+    // Note WHICH check catches it. The envelope is fine; it is the payload that
+    // no longer matches its declaration. A suite leading with `envelopeViolations`
+    // alone would pass this body, which is exactly how it would ship.
+    const body = { success: true, data: [ASK, BUILD] };
+    expect(envelopeViolations(body)).toEqual([]);
+    expect(AiAgentsResponseSchema.safeParse(body.data).success).toBe(false);
+    expect(servesTheDeclaredShape(body)).toBe(false);
+  });
+
+  it('the pre-#4053 bare body — no flag for `unwrapResponse` to key on', () => {
+    const body = { agents: [ASK] };
+    expect(servesTheDeclaredShape(body)).toBe(false);
+    expect(envelopeViolations(body)).toContain('success is missing, must be a boolean');
+  });
+
+  it('the duplicate-payload shim — `agents` kept alive beside `data`', () => {
+    // The drift #4038 / #4049 removed from `/share-links`: the payload under
+    // both spellings, so no consumer ever has to choose and neither dialect
+    // dies. Here the mirrored key catches it; the payload itself is valid.
+    const body = { success: true, data: { agents: [ASK] }, agents: [ASK] };
+    expect(envelopeViolations(body)).toEqual([
+      'stray top-level key `agents` — the payload belongs under `data`',
+    ]);
+    expect(servesTheDeclaredShape(body)).toBe(false);
+  });
+
+  it('an agent row without `capabilities` — the field UI affordances branch on', () => {
+    // cloud#816 / ADR-0057 "B+": hosts render debug drawer, Live Canvas and
+    // resume-vs-fresh BY CAPABILITY. A row missing it is not a row this route
+    // returns, so it fails the payload half even inside a clean envelope.
+    const body = { success: true, data: { agents: [{ name: 'build', label: 'Build', role: 'authoring' }] } };
+    expect(envelopeViolations(body)).toEqual([]);
+    expect(servesTheDeclaredShape(body)).toBe(false);
+  });
+});
diff --git a/packages/spec/src/api/envelope-violations.test.ts b/packages/spec/src/api/envelope-violations.test.ts
index 345820efe9..888c9e761e 100644
--- a/packages/spec/src/api/envelope-violations.test.ts
+++ b/packages/spec/src/api/envelope-violations.test.ts
@@ -88,7 +88,11 @@ describe('envelopeViolations — what the schema MISSES', () => {
   });
 
   it('a payload left at the top level beside the flag', () => {
-    // The shape `GET /ai/agents` still answers in, minus the flag (#4053).
+    // The shim `GET /ai/agents` would have grown had it kept `agents` alive
+    // beside `data` through the conversion. It did not — both producers moved
+    // the payload rather than mirroring it (#4053) — and this is the check that
+    // would have said so. See `ai-agents-envelope.test.ts` for that route's own
+    // pins, including the half this predicate deliberately does not cover.
     const body = { success: true, data: [], agents: [] };
     expect(parses(body)).toBe(true);
     expect(conformant(body)).toBe(false);
diff --git a/packages/spec/src/api/protocol.zod.ts b/packages/spec/src/api/protocol.zod.ts
index 4556ec7def..f5b1f70b7b 100644
--- a/packages/spec/src/api/protocol.zod.ts
+++ b/packages/spec/src/api/protocol.zod.ts
@@ -1069,7 +1069,23 @@ export const AiAgentSummarySchema = lazySchema(() => z.object({
 }));
 
 /**
- * `GET /api/v1/ai/agents`.
+ * `GET /api/v1/ai/agents` — the **`data` payload**, not the whole body.
+ *
+ * The body is the platform envelope (`BaseResponseSchema`), and this schema is
+ * what travels under `data`: `{ success: true, data: { agents: [...] } }`. It
+ * was declared as the whole body until #4053 converted the route, and moving it
+ * under `data` was a RELOCATION — the payload is unchanged, exactly as
+ * `SettingsNamespacePayload` moved in #3843, not a flatten to the bare array the
+ * way #3983 reshaped `/share-links`.
+ *
+ * That distinction is load-bearing, which is why it is recorded on the
+ * declaration rather than only at the two producers. `unwrapResponse` returns
+ * `data`, so `client.ai.agents.list()` reads `.agents` off this object; flattening
+ * to `data: [...]` would make that read `undefined` → an empty catalog, which
+ * `useAiSurfaceEnabled` turns into "hide the entire AI surface" — the same thing a
+ * seat-less caller and a Community-Edition deployment correctly see, with no
+ * error, no 403 and no log to tell them apart. `ai-agents-envelope.test.ts` pins
+ * both halves.
  *
  * ACCESS-AWARE: the route returns only agents the CALLER may chat with
  * (ADR-0049), so an empty list is a legitimate answer for a seat-less user —