diff --git a/src/logging/diagnostic-stability.test.ts b/src/logging/diagnostic-stability.test.ts
index 549160e2964..733796a2d3e 100644
--- a/src/logging/diagnostic-stability.test.ts
+++ b/src/logging/diagnostic-stability.test.ts
@@ -22,7 +22,7 @@ describe("diagnostic stability recorder", () => {
     resetDiagnosticEventsForTest();
   });
 
-  it("records a bounded payload-free projection of diagnostic events", () => {
+  it("records a bounded payload-free projection of diagnostic events", async () => {
     startDiagnosticStabilityRecorder();
 
     emitDiagnosticEvent({
@@ -41,13 +41,29 @@ describe("diagnostic stability recorder", () => {
       count: 3,
       message: "message that should not be stored",
     });
+    emitDiagnosticEvent({
+      type: "talk.event",
+      sessionId: "talk-session-secret",
+      turnId: "talk-turn-secret",
+      captureId: "talk-capture-secret",
+      talkEventType: "latency.metrics",
+      mode: "realtime",
+      transport: "gateway-relay",
+      brain: "agent-consult",
+      provider: "openai",
+      final: true,
+      durationMs: 12,
+      byteLength: 345,
+    });
+    await new Promise<void>((resolve) => setImmediate(resolve));
 
     const snapshot = getDiagnosticStabilitySnapshot({ limit: 10 });
 
-    expect(snapshot.count).toBe(2);
+    expect(snapshot.count).toBe(3);
     expect(snapshot.summary.byType).toMatchObject({
       "webhook.error": 1,
       "tool.loop": 1,
+      "talk.event": 1,
     });
     expect(snapshot.events[0]).toMatchObject({
       type: "webhook.error",
@@ -66,6 +82,20 @@ describe("diagnostic stability recorder", () => {
     expect(snapshot.events[1]).not.toHaveProperty("message");
     expect(snapshot.events[1]).not.toHaveProperty("sessionId");
     expect(snapshot.events[1]).not.toHaveProperty("sessionKey");
+    expect(snapshot.events[2]).toMatchObject({
+      type: "talk.event",
+      talkEventType: "latency.metrics",
+      mode: "realtime",
+      transport: "gateway-relay",
+      brain: "agent-consult",
+      provider: "openai",
+      final: true,
+      durationMs: 12,
+      bytes: 345,
+    });
+    expect(snapshot.events[2]).not.toHaveProperty("sessionId");
+    expect(snapshot.events[2]).not.toHaveProperty("turnId");
+    expect(snapshot.events[2]).not.toHaveProperty("captureId");
   });
 
   it("keeps stable reason codes but drops free-form reason text", () => {
diff --git a/src/logging/diagnostic-stability.ts b/src/logging/diagnostic-stability.ts
index 1266c113a63..796ae68a4e7 100644
--- a/src/logging/diagnostic-stability.ts
+++ b/src/logging/diagnostic-stability.ts
@@ -27,6 +27,9 @@ export type DiagnosticStabilityEventRecord = {
   phase?: string;
   detector?: string;
   deliveryKind?: string;
+  talkEventType?: string;
+  transport?: string;
+  brain?: string;
   toolName?: string;
   activeWorkKind?: string;
   pairedToolName?: string;
@@ -40,6 +43,7 @@ export type DiagnosticStabilityEventRecord = {
   commandLength?: number;
   exitCode?: number;
   timedOut?: boolean;
+  final?: boolean;
   costUsd?: number;
   count?: number;
   bytes?: number;
@@ -228,6 +232,16 @@ function sanitizeDiagnosticEvent(event: DiagnosticEventPayload): DiagnosticStabi
       record.outcome = "error";
       assignReasonCode(record, event.errorCategory);
       break;
+    case "talk.event":
+      record.talkEventType = event.talkEventType;
+      record.mode = event.mode;
+      record.transport = event.transport;
+      record.brain = event.brain;
+      record.provider = event.provider;
+      record.final = event.final;
+      record.durationMs = event.durationMs;
+      record.bytes = event.byteLength;
+      break;
     case "session.state":
       record.outcome = event.state;
       assignReasonCode(record, event.reason);