fix(agent-gateway): seed agent phase when a transcript attaches mid-turn

.changeset/transcript-phase-on-attach.md

@@ -0,0 +1,5 @@
+---
+"@pymodel/pythinker-code": patch
+---
+
+Clients that open a session while a tool approval is pending now show the agent's status instead of none.

packages/agent-gateway/src/services/transcript/coreBinding.ts

@@ -155,6 +155,7 @@ export function bindSessionTranscript(
     if (loopStatus?.state === 'running' && loopStatus.activeTurnId !== undefined) {
       const promptId = loopStatus.activePromptId;
       projector.seedActiveTurn({ turnId: loopStatus.activeTurnId, promptId });
+      applyOps(handle.id, projector.seedPhase());
     }
     const list = agentDisposables.get(handle.id) ?? [];
     list.push(busD);

packages/agent-gateway/src/services/transcript/coreEventMap.ts

@@ -357,15 +357,25 @@ export class AgentTranscriptProjector {
     return [...ops, { op: 'meta.merge', meta: { agent: { phase } } }];
   }
 
-  private phaseFor(event: ProjectorBusEvent): ReturnType<typeof toLegacyPhase> {
+  seedPhase(): TranscriptOperation[] {
+    const phase = this.tracker()?.recompute();
+    return phase === undefined ? [] : [{ op: 'meta.merge', meta: { agent: { phase } } }];
+  }
+
+  private tracker(): LegacyActivityTracker | undefined {
     if (this.lookups?.activitySnapshot === undefined || this.lookups.pendingApprovals === undefined) {
       return undefined;
     }
     this.activityTracker ??= new LegacyActivityTracker(
       this.lookups.activitySnapshot,
       this.lookups.pendingApprovals,
     );
-    return phaseFromDomainEvent(this.activityTracker, event);
+    return this.activityTracker;
+  }
+
+  private phaseFor(event: ProjectorBusEvent): ReturnType<typeof toLegacyPhase> {
+    const tracker = this.tracker();
+    return tracker === undefined ? undefined : phaseFromDomainEvent(tracker, event);
   }
 
   private mapEvent(event: ProjectorBusEvent): TranscriptOperation[] {

packages/agent-gateway/test/services/transcript.test.ts

@@ -1597,6 +1597,24 @@ describe('AgentTranscriptProjector', () => {
     expect(tx.getMeta().agent).toMatchObject({ model: 'k3', thinkingEffort: 'high' });
   });
 
+  it('seeds meta.agent.phase when attaching to a turn blocked on an approval', () => {
+    const projector = new AgentTranscriptProjector('main', TEST_SESSION_ID, {
+      activitySnapshot: () => ({
+        turn: { turnId: 1, phase: 'running', step: 1, ending: false, activeToolCalls: [], since: 1000 },
+      }),
+      pendingApprovals: () => [{ approvalId: 'ap1', toolCallId: 'c1', since: 1500 }],
+    });
+    const tx = new AgentTranscript('main');
+
+    tx.apply(projector.seedPhase());
+
+    expect(tx.getMeta().agent?.phase).toMatchObject({
+      kind: 'awaiting_approval',
+      turnId: 1,
+      approval: { approvalId: 'ap1', toolCallId: 'c1' },
+    });
+  });
+
   it('maps domain events into meta.agent.phase', () => {
     let snapshot: AgentActivitySnapshot = {};
     let approvals: readonly LegacyActivityApproval[] = [];