refactor(chat): route browser chat through one runtime

Co-Authored-By: Claude Opus 4.8 <[email protected]>
Claude-Session: https://claude.ai/code/session_01ESFAnh2t9HmLwng8oW95St

apps/gateway/src/agent/__tests__/session-ownership.test.ts

@@ -863,4 +863,96 @@ describe('TESS Task-5 embedded REST turn teardown (a prompt rejection frees the
     process.off('unhandledRejection', onUnhandled);
     expect(unhandled).toHaveLength(0);
   });
+
+  it('bounds a hung prompt: when prompt() never settles and no agent_end arrives, the 120s timeout ends the turn with a timeout result and exactly one teardown, no unhandledRejection (Task 5 finding 6 — pending-prompt timeout)', async () => {
+    const session = makeAgentSession(USER_A);
+    const detach = vi.fn();
+    const svc = {
+      getSession: vi.fn(() => session),
+      createSession: vi.fn(),
+      onEvent: vi.fn(() => detach),
+      addChannel: vi.fn(),
+      removeChannel: vi.fn(),
+      // The prompt never resolves or rejects — a hung agent backend. Under the pre-fix sequential
+      // `await prompt()` the timer could never even be observed, so the turn hung forever.
+      prompt: vi.fn(() => new Promise<void>(() => undefined)),
+      recordTokenUsage: vi.fn(),
+    };
+    const runtime = new EmbeddedChatRuntime(svc as never);
+
+    const unhandled: unknown[] = [];
+    const onUnhandled = (reason: unknown): void => {
+      unhandled.push(reason);
+    };
+    process.on('unhandledRejection', onUnhandled);
+    vi.useFakeTimers();
+    try {
+      const resultPromise = runtime.completeLegacyRestTurn(ctx, {
+        content: 'a prompt that never returns',
+      });
+      // No agent_end, prompt still pending: only the 120s timeout can end the turn. Promise.all
+      // installed a handler on `done` synchronously, so the timer bounds the turn while prompt hangs.
+      await vi.advanceTimersByTimeAsync(200_000);
+      const result = await resultPromise;
+
+      expect(result).toEqual({ ok: false, code: 'timeout', retryable: true });
+      // The single idempotent dispose ran on the timeout path: listener detached exactly once.
+      expect(detach).toHaveBeenCalledTimes(1);
+      // Advancing far past the deadline fires nothing more: dispose cleared the timer.
+      vi.advanceTimersByTime(600_000);
+      expect(detach).toHaveBeenCalledTimes(1);
+    } finally {
+      vi.useRealTimers();
+    }
+    await new Promise((resolve) => setTimeout(resolve, 0));
+    process.off('unhandledRejection', onUnhandled);
+    expect(unhandled).toHaveLength(0);
+  });
+
+  it('when the 120s timeout fires while prompt() is still pending, returns timeout with one teardown, and a later prompt rejection surfaces no unhandledRejection (Task 5 finding 6 — timeout/prompt race)', async () => {
+    const session = makeAgentSession(USER_A);
+    const detach = vi.fn();
+    let rejectPrompt: (reason: unknown) => void = () => undefined;
+    const prompting = new Promise<void>((_resolve, reject) => {
+      rejectPrompt = reject;
+    });
+    const svc = {
+      getSession: vi.fn(() => session),
+      createSession: vi.fn(),
+      onEvent: vi.fn(() => detach),
+      addChannel: vi.fn(),
+      removeChannel: vi.fn(),
+      prompt: vi.fn(() => prompting),
+      recordTokenUsage: vi.fn(),
+    };
+    const runtime = new EmbeddedChatRuntime(svc as never);
+
+    const unhandled: unknown[] = [];
+    const onUnhandled = (reason: unknown): void => {
+      unhandled.push(reason);
+    };
+    process.on('unhandledRejection', onUnhandled);
+    vi.useFakeTimers();
+    try {
+      const resultPromise = runtime.completeLegacyRestTurn(ctx, {
+        content: 'prompt settles after the deadline',
+      });
+      // The timeout wins the race while prompt is still pending.
+      await vi.advanceTimersByTimeAsync(200_000);
+      const result = await resultPromise;
+
+      expect(result).toEqual({ ok: false, code: 'timeout', retryable: true });
+      expect(detach).toHaveBeenCalledTimes(1);
+
+      // The prompt now rejects LATE — after the turn already returned its timeout result. Because
+      // Promise.all installed a rejection handler on `prompting` synchronously (the fix), this late
+      // rejection is already observed and must not escape as an unhandledRejection.
+      rejectPrompt(new Error('late backend failure'));
+    } finally {
+      vi.useRealTimers();
+    }
+    await new Promise((resolve) => setTimeout(resolve, 0));
+    process.off('unhandledRejection', onUnhandled);
+    expect(unhandled).toHaveLength(0);
+  });
 });

apps/gateway/src/chat/__tests__/chat-security.test.ts

@@ -967,7 +967,11 @@ describe('Non-Discord ("Telegram-equivalent") socket ingress rejection (Task Fiv
       prompt: vi.fn().mockResolvedValue(undefined),
     };
     const harnessConversations = { append: vi.fn() };
-    const create = vi.fn().mockResolvedValue(undefined);
+    // The durable store honours the mint: it returns the exact record asked for (same id, same
+    // scoped owner). Admission requires that non-null, correctly-identified record before any effect.
+    const create = vi.fn((data: { id: string; userId: string }) =>
+      Promise.resolve({ id: data.id, userId: data.userId }),
+    );
     const brain = {
       conversations: {
         findById: vi.fn().mockResolvedValue(undefined),
@@ -1009,6 +1013,159 @@ describe('Non-Discord ("Telegram-equivalent") socket ingress rejection (Task Fiv
     expect(agentService.prompt).toHaveBeenCalledTimes(1);
     expect(harnessConversations.append).not.toHaveBeenCalled();
   });
+
+  it('fails a legacy browser send with NO conversationId closed when the durable mint resolves nullish, with zero dispatch/persist/prompt/ack (Task 5 finding 1)', async () => {
+    // Minting is not fire-and-forget: if create resolves nullish (the durable write silently
+    // produced no record), admission must fail closed BEFORE any runtime effect rather than dispatch
+    // against a conversation that was never persisted.
+    process.env['CHAT_HARNESS_RUNTIME'] = 'legacy';
+    const order: string[] = [];
+    const counters = { dispatch: 0, dispose: 0 };
+    const session = {
+      provider: 'configured-provider',
+      modelId: 'configured-model',
+      piSession: {
+        thinkingLevel: 'medium',
+        getAvailableThinkingLevels: (): string[] => ['medium'],
+      },
+    };
+    const agentService = {
+      getSession: vi.fn().mockReturnValue(undefined),
+      createSession: vi.fn().mockResolvedValue(session),
+      recordMessage: vi.fn(),
+      onEvent: vi.fn().mockReturnValue((): void => undefined),
+      addChannel: vi.fn(),
+      removeChannel: vi.fn(),
+      prompt: vi.fn().mockResolvedValue(undefined),
+    };
+    const harnessConversations = { append: vi.fn() };
+    const create = vi.fn().mockResolvedValue(undefined);
+    const addMessage = vi.fn().mockResolvedValue({ id: 'persisted-new' });
+    const brain = {
+      conversations: {
+        findById: vi.fn().mockResolvedValue(undefined),
+        findMessages: vi.fn().mockResolvedValue([]),
+        create,
+        update: vi.fn().mockResolvedValue(undefined),
+        addMessage,
+      },
+    };
+    const router = readyRouter('legacy', agentService, harnessConversations);
+    instrumentLease(router, order, counters);
+    const gateway = new ChatGateway(
+      router as never,
+      { api: { getSession: vi.fn() } } as never,
+      brain as never,
+      {} as never,
+      {} as never,
+      {} as never,
+    );
+    const client = {
+      id: 'browser-new-nullish-1',
+      data: { user: { id: 'user-a' } },
+      emit: vi.fn(),
+    };
+
+    await gateway.handleMessage(
+      client as never,
+      {
+        content: 'first message, mint resolves nullish',
+      } as never,
+    );
+
+    // The mint was attempted for the sender, then admission failed closed: no persist, no session
+    // mint, no lease dispatch/dispose, no prompt, no ack — only the typed refusal.
+    expect(create).toHaveBeenCalledWith(
+      expect.objectContaining({ id: expect.any(String), userId: 'user-a' }),
+    );
+    expect(addMessage).not.toHaveBeenCalled();
+    expect(agentService.createSession).not.toHaveBeenCalled();
+    expect(agentService.prompt).not.toHaveBeenCalled();
+    expect(counters.dispatch).toBe(0);
+    expect(counters.dispose).toBe(0);
+    expect(client.emit).not.toHaveBeenCalledWith('message:ack', expect.anything());
+    expect(client.emit).toHaveBeenCalledWith(
+      'error',
+      expect.objectContaining({ code: 'conversation_unavailable' }),
+    );
+    expect(harnessConversations.append).not.toHaveBeenCalled();
+  });
+
+  it('fails a legacy browser send with NO conversationId closed when the durable mint throws, with zero dispatch/persist/prompt/ack (Task 5 finding 1)', async () => {
+    // A create that rejects (durable store error) is a persistence failure, not a reason to proceed:
+    // the exception is caught at the admission seam and collapses to the same fail-closed refusal.
+    process.env['CHAT_HARNESS_RUNTIME'] = 'legacy';
+    const order: string[] = [];
+    const counters = { dispatch: 0, dispose: 0 };
+    const session = {
+      provider: 'configured-provider',
+      modelId: 'configured-model',
+      piSession: {
+        thinkingLevel: 'medium',
+        getAvailableThinkingLevels: (): string[] => ['medium'],
+      },
+    };
+    const agentService = {
+      getSession: vi.fn().mockReturnValue(undefined),
+      createSession: vi.fn().mockResolvedValue(session),
+      recordMessage: vi.fn(),
+      onEvent: vi.fn().mockReturnValue((): void => undefined),
+      addChannel: vi.fn(),
+      removeChannel: vi.fn(),
+      prompt: vi.fn().mockResolvedValue(undefined),
+    };
+    const harnessConversations = { append: vi.fn() };
+    const create = vi.fn().mockRejectedValue(new Error('durable store unavailable'));
+    const addMessage = vi.fn().mockResolvedValue({ id: 'persisted-new' });
+    const brain = {
+      conversations: {
+        findById: vi.fn().mockResolvedValue(undefined),
+        findMessages: vi.fn().mockResolvedValue([]),
+        create,
+        update: vi.fn().mockResolvedValue(undefined),
+        addMessage,
+      },
+    };
+    const router = readyRouter('legacy', agentService, harnessConversations);
+    instrumentLease(router, order, counters);
+    const gateway = new ChatGateway(
+      router as never,
+      { api: { getSession: vi.fn() } } as never,
+      brain as never,
+      {} as never,
+      {} as never,
+      {} as never,
+    );
+    const client = {
+      id: 'browser-new-throw-1',
+      data: { user: { id: 'user-a' } },
+      emit: vi.fn(),
+    };
+
+    await gateway.handleMessage(
+      client as never,
+      {
+        content: 'first message, mint throws',
+      } as never,
+    );
+
+    // The mint was attempted for the sender, then admission failed closed on the thrown error: no
+    // persist, no session mint, no lease dispatch/dispose, no prompt, no ack — only the typed refusal.
+    expect(create).toHaveBeenCalledWith(
+      expect.objectContaining({ id: expect.any(String), userId: 'user-a' }),
+    );
+    expect(addMessage).not.toHaveBeenCalled();
+    expect(agentService.createSession).not.toHaveBeenCalled();
+    expect(agentService.prompt).not.toHaveBeenCalled();
+    expect(counters.dispatch).toBe(0);
+    expect(counters.dispose).toBe(0);
+    expect(client.emit).not.toHaveBeenCalledWith('message:ack', expect.anything());
+    expect(client.emit).toHaveBeenCalledWith(
+      'error',
+      expect.objectContaining({ code: 'conversation_unavailable' }),
+    );
+    expect(harnessConversations.append).not.toHaveBeenCalled();
+  });
 });
 
 describe('Chat DTO validation', () => {

apps/gateway/src/chat/chat.gateway.ts

@@ -492,16 +492,17 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
     );
 
     // Reconcile the verified binding against the durable agent record BEFORE claiming the message
-    // id (security fix, finding 3). The configured agent must exist and its record name must match
+    // id (security fix, finding 3). The configured agent must exist and its record must match the
-    // the binding's instance id exactly; a missing record, a name mismatch, or a lookup error
+    // binding EXACTLY on BOTH id and name — a record whose id differs from the binding's
-    // rejects the turn WITHOUT consuming the replay claim, so a corrected retry is still admitted.
+    // agentConfigId (an aliased/substituted lookup) is rejected as firmly as a name mismatch. A
-    // The branded identity is derived from the record (id + name), never from the raw binding
+    // missing record, an id mismatch, a name mismatch, or a lookup error rejects the turn WITHOUT
-    // strings — an unreconciled binding must not execute a default or different embedded agent
+    // consuming the replay claim, so a corrected retry is still admitted. The branded identity is
-    // under a verified label.
+    // derived from the record (id + name), never from the raw binding strings — an unreconciled
+    // binding must not execute a default or different embedded agent under a verified label.
     let configuredAgent: { readonly agentConfigId: string; readonly instanceId: string };
     try {
       const record = await this.brain.agents.findById(binding.agentConfigId);
-      if (!record || record.name !== binding.instanceId) {
+      if (!record || record.id !== binding.agentConfigId || record.name !== binding.instanceId) {
         this.logger.warn(
           `Rejected Discord ingress: configured agent not reconciled binding=${binding.agentConfigId} instance=${binding.instanceId}`,
         );
@@ -1164,8 +1165,12 @@ export class ChatGateway implements OnGatewayInit, OnGatewayConnection, OnGatewa
         const owned = await this.brain.conversations.findById(suppliedConversationId, userId);
         return owned !== undefined;
       }
-      await this.brain.conversations.create({ id: conversationId, userId });
+      // Minting a new conversation must actually yield the durable record we asked for before any
-      return true;
+      // runtime effect runs (finding 1). A `create` that resolves nullish, or returns a record that
+      // is not this exact id owned by this user, is a persistence failure — fail closed so the caller
+      // never dispatches/persists against an unpersisted or mis-scoped conversation.
+      const created = await this.brain.conversations.create({ id: conversationId, userId });
+      return created != null && created.id === conversationId && created.userId === userId;
     } catch (err) {
       this.logger.error(
         `Conversation admission failed for conversation=${conversationId}`,

apps/gateway/src/chat/embedded-chat.runtime.ts

@@ -94,9 +94,16 @@ export class EmbeddedChatRuntime implements ChatRuntime, LegacyEmbeddedChatPort
       );
     });
 
+    // Attach the prompt and the completion promise CONCURRENTLY. Awaiting prompt() first left the
+    // timeout unobservable until prompt settled (a hung prompt could never time out) and, worse,
+    // let the 120s timer reject `done` while nothing yet awaited it — a transient unhandledRejection
+    // window. Promise.all installs handlers on BOTH synchronously, so the timeout bounds the whole
+    // turn even while prompt is pending, and neither promise can reject unobserved. Success still
+    // requires both prompt() to resolve AND agent_end to arrive (identical to the prior sequential
+    // await). The idempotent dispose() clears the timer + detaches on whichever settles first.
+    const prompting = this.agentService.prompt(conversationId, input.content, scope);
     try {
-      await this.agentService.prompt(conversationId, input.content, scope);
+      await Promise.all([prompting, done]);
-      await done;
     } catch (err) {
       dispose();
       const message = err instanceof Error ? err.message : String(err);
@@ -300,18 +307,22 @@ export class EmbeddedChatRuntime implements ChatRuntime, LegacyEmbeddedChatPort
     | { readonly ok: true; readonly presentation: LegacySessionPresentation }
     | Exclude<LegacyRuntimeResult<never>, { ok: true }>
   > {
+    // A verified-Discord turn may only run under a session whose configured identity matches the
+    // reconciled agent record EXACTLY (config id + resolved name). This holds for BOTH a reused
+    // pre-existing session AND a freshly created one: a session carrying a different configured
+    // agent — however it arose — is rejected rather than executed under the verified label, so we
+    // never silently run a different prompt/model/tool policy. A plain (non-verified) turn passes
+    // no expectedAgent and skips the check.
+    const identityMatches = (candidate: AgentSession): boolean =>
+      expectedAgent === undefined ||
+      (candidate.agentConfigId === expectedAgent.agentConfigId &&
+        candidate.agentName === expectedAgent.instanceId);
+
     let session = this.agentService.getSession(conversationId, scope);
-    if (session && expectedAgent) {
+    if (session && !identityMatches(session)) {
-      // A verified-Discord turn reuses an existing in-process session only when its configured
+      // Reused same-scope session minted under a different configured identity — reject with zero
-      // identity still matches the reconciled agent record. A pre-existing same-scope session
+      // effects rather than dispatch a verified turn onto a foreign agent's session.
-      // carrying a different configured agent (config id or resolved name) is rejected rather than
+      return CONVERSATION_UNAVAILABLE;
-      // executed under the verified label — never silently run a different prompt/model/tool policy.
-      if (
-        session.agentConfigId !== expectedAgent.agentConfigId ||
-        session.agentName !== expectedAgent.instanceId
-      ) {
-        return CONVERSATION_UNAVAILABLE;
-      }
     }
     if (!session) {
       try {
@@ -330,6 +341,12 @@ export class EmbeddedChatRuntime implements ChatRuntime, LegacyEmbeddedChatPort
         );
         return { ok: false, code: 'runtime_unavailable', retryable: true };
       }
+      // The just-created session must ALSO carry the reconciled identity before any effect. A
+      // createSession that returns a session under a different configured agent (misconfiguration
+      // or a substituted factory) is rejected here, before subscribe/persist/ack/prompt.
+      if (!identityMatches(session)) {
+        return CONVERSATION_UNAVAILABLE;
+      }
     }
     return { ok: true, presentation: this.presentationForSession(session) };
   }

apps/gateway/src/plugin/discord-ingress.security.spec.ts

@@ -612,6 +612,8 @@ describe('Discord ingress security', () => {
     const session = {
       provider: 'configured-provider',
       modelId: 'configured-model',
+      agentConfigId: 'agent-config-nova',
+      agentName: 'Nova',
       piSession: {
         thinkingLevel: 'medium',
         getAvailableThinkingLevels: (): string[] => ['medium'],
@@ -697,6 +699,8 @@ describe('Discord ingress security', () => {
     const session = {
       provider: 'configured-provider',
       modelId: 'configured-model',
+      agentConfigId: 'agent-config-nova',
+      agentName: 'Nova',
       piSession: {
         thinkingLevel: 'medium',
         getAvailableThinkingLevels: (): string[] => ['medium'],
@@ -796,6 +800,8 @@ describe('Discord ingress security', () => {
     const session = {
       provider: 'configured-provider',
       modelId: 'configured-model',
+      agentConfigId: 'agent-config-nova',
+      agentName: 'Nova',
       piSession: {
         thinkingLevel: 'medium',
         getAvailableThinkingLevels: (): string[] => ['medium'],
@@ -963,6 +969,197 @@ describe('Discord ingress security', () => {
     expect(harnessConversations.append).not.toHaveBeenCalled();
   });
 
+  it('a verified SEND whose configured agent record resolves under a different id fails reconciliation, consumes no replay claim, and a corrected byte-identical retry dispatches/persists/acks exactly once (Task 5 finding 3 — id axis)', async () => {
+    configureDiscordEnv();
+    process.env['CHAT_HARNESS_RUNTIME'] = 'pi-rpc';
+    process.env['DISCORD_ALLOWED_CHANNEL_IDS'] = 'channel-001';
+    process.env['DISCORD_INTERACTION_BINDINGS'] = JSON.stringify([
+      {
+        instanceId: 'Nova',
+        agentConfigId: 'agent-config-nova',
+        guildId: 'guild-001',
+        channelId: 'channel-001',
+        pairedUsers: {
+          'user-001': { role: 'operator', mosaicUserId: 'mosaic-operator-001' },
+        },
+      },
+    ]);
+    const session = {
+      provider: 'configured-provider',
+      modelId: 'configured-model',
+      agentConfigId: 'agent-config-nova',
+      agentName: 'Nova',
+      piSession: {
+        thinkingLevel: 'medium',
+        getAvailableThinkingLevels: (): string[] => ['medium'],
+      },
+    };
+    const createSession = vi.fn().mockResolvedValue(session);
+    const prompt = vi.fn().mockResolvedValue(undefined);
+    const agentService = {
+      getSession: vi.fn().mockReturnValue(undefined),
+      createSession,
+      recordMessage: vi.fn(),
+      onEvent: vi.fn().mockReturnValue((): void => undefined),
+      addChannel: vi.fn(),
+      removeChannel: vi.fn(),
+      prompt,
+    };
+    const addMessage = vi.fn().mockResolvedValue({ id: 'discord-persisted-message' });
+    // The name matches the verified binding, but the record's own id is a DIFFERENT agent config —
+    // an aliased/substituted lookup. Exact-id reconciliation must refuse it on the first delivery,
+    // then admit the corrected record whose id matches the binding.
+    const findAgent = vi
+      .fn()
+      .mockResolvedValueOnce({ id: 'agent-config-elsewhere', name: 'Nova' })
+      .mockResolvedValue({ id: 'agent-config-nova', name: 'Nova' });
+    const brain = {
+      agents: { findById: findAgent },
+      conversations: {
+        findById: vi.fn().mockResolvedValue({ id: 'Nova:discord:channel-001' }),
+        findMessages: vi.fn().mockResolvedValue([]),
+        create: vi.fn().mockResolvedValue(undefined),
+        update: vi.fn().mockResolvedValue(undefined),
+        addMessage,
+      },
+    };
+    const harnessConversations = { append: vi.fn() };
+    const gateway = new ChatGateway(
+      piRpcRouterFronting(agentService, harnessConversations) as never,
+      {} as never,
+      brain as never,
+      {} as never,
+      {} as never,
+      { resolve: vi.fn() } as never,
+    );
+    const client = {
+      id: 'discord-client-reconcile-id',
+      data: { discordService: true },
+      emit: vi.fn(),
+    };
+    const ackCount = (): number =>
+      client.emit.mock.calls.filter((call) => call[0] === 'message:ack').length;
+
+    const envelope = ingressEnvelope(
+      'verified once with aliased agent id',
+      'discord-reconcile-id-001',
+      {
+        conversationId: 'Nova:discord:channel-001',
+      },
+    );
+
+    // (1) The record's id differs from the binding's agentConfigId. Exact-id reconcile refuses the
+    //     turn BEFORE the replay claim, so nothing dispatches and the claim stays available.
+    await gateway.handleMessage(client as never, envelope);
+    expect(createSession).toHaveBeenCalledTimes(0);
+    expect(prompt).toHaveBeenCalledTimes(0);
+    expect(addMessage).toHaveBeenCalledTimes(0);
+    expect(ackCount()).toBe(0);
+
+    // (2) The record now reconciles on both id and name; because step (1) took no claim, this
+    //     byte-identical retry claims once and runs the full embedded dispatch exactly once.
+    await gateway.handleMessage(client as never, envelope);
+    expect(createSession).toHaveBeenCalledTimes(1);
+    expect(prompt).toHaveBeenCalledTimes(1);
+    expect(addMessage).toHaveBeenCalledTimes(1);
+    expect(ackCount()).toBe(1);
+
+    // (3) A genuine duplicate after the committed turn stays fail-closed.
+    await gateway.handleMessage(client as never, envelope);
+    expect(createSession).toHaveBeenCalledTimes(1);
+    expect(prompt).toHaveBeenCalledTimes(1);
+    expect(addMessage).toHaveBeenCalledTimes(1);
+    expect(ackCount()).toBe(1);
+    expect(harnessConversations.append).not.toHaveBeenCalled();
+  });
+
+  it('a verified SEND refuses a freshly minted same-scope session whose identity differs from the reconciled configured agent, with zero prompt/persist/ack (Task 5 finding 3 — post-create)', async () => {
+    configureDiscordEnv();
+    process.env['CHAT_HARNESS_RUNTIME'] = 'pi-rpc';
+    process.env['DISCORD_ALLOWED_CHANNEL_IDS'] = 'channel-001';
+    process.env['DISCORD_INTERACTION_BINDINGS'] = JSON.stringify([
+      {
+        instanceId: 'Nova',
+        agentConfigId: 'agent-config-nova',
+        guildId: 'guild-001',
+        channelId: 'channel-001',
+        pairedUsers: {
+          'user-001': { role: 'operator', mosaicUserId: 'mosaic-operator-001' },
+        },
+      },
+    ]);
+    // No live session exists for this scope, so the runtime MINTS one — but createSession returns a
+    // session carrying a DIFFERENT configured identity (Orion) than the reconciled binding (Nova).
+    // The post-create identity recheck must refuse it rather than dispatch one agent's turn under
+    // another agent's verified label. (The existing reuse test covers the getSession path; this
+    // covers the createSession path scrappy flagged as unvalidated.)
+    const mintedForeignSession = {
+      provider: 'configured-provider',
+      modelId: 'configured-model',
+      agentConfigId: 'agent-config-orion',
+      agentName: 'Orion',
+      piSession: {
+        thinkingLevel: 'medium',
+        getAvailableThinkingLevels: (): string[] => ['medium'],
+      },
+    };
+    const prompt = vi.fn().mockResolvedValue(undefined);
+    const createSession = vi.fn().mockResolvedValue(mintedForeignSession);
+    const agentService = {
+      getSession: vi.fn().mockReturnValue(undefined),
+      createSession,
+      recordMessage: vi.fn(),
+      onEvent: vi.fn().mockReturnValue((): void => undefined),
+      addChannel: vi.fn(),
+      removeChannel: vi.fn(),
+      prompt,
+    };
+    const addMessage = vi.fn().mockResolvedValue({ id: 'discord-persisted-message' });
+    const brain = {
+      agents: { findById: vi.fn((id: string) => Promise.resolve({ id, name: 'Nova' })) },
+      conversations: {
+        findById: vi.fn().mockResolvedValue({ id: 'Nova:discord:channel-001' }),
+        findMessages: vi.fn().mockResolvedValue([]),
+        create: vi.fn().mockResolvedValue(undefined),
+        update: vi.fn().mockResolvedValue(undefined),
+        addMessage,
+      },
+    };
+    const harnessConversations = { append: vi.fn() };
+    const gateway = new ChatGateway(
+      piRpcRouterFronting(agentService, harnessConversations) as never,
+      {} as never,
+      brain as never,
+      {} as never,
+      {} as never,
+      { resolve: vi.fn() } as never,
+    );
+    const client = {
+      id: 'discord-client-postcreate-mismatch',
+      data: { discordService: true },
+      emit: vi.fn(),
+    };
+
+    await gateway.handleMessage(
+      client as never,
+      ingressEnvelope('mint under a different identity', 'discord-postcreate-001', {
+        conversationId: 'Nova:discord:channel-001',
+      }),
+    );
+
+    // The freshly minted session failed the post-create identity recheck: refused with a typed
+    // error, no prompt, no persist, no ack.
+    expect(createSession).toHaveBeenCalledTimes(1);
+    expect(prompt).not.toHaveBeenCalled();
+    expect(addMessage).not.toHaveBeenCalled();
+    expect(client.emit).not.toHaveBeenCalledWith('message:ack', expect.anything());
+    expect(client.emit).toHaveBeenCalledWith(
+      'error',
+      expect.objectContaining({ conversationId: 'Nova:discord:channel-001' }),
+    );
+    expect(harnessConversations.append).not.toHaveBeenCalled();
+  });
+
   it('retains validated persisted attachments in resumed conversation history', async () => {
     const attachment = {
       id: 'attachment-history',