diff --git a/open-sse/handlers/chatCore/attemptLogging.ts b/open-sse/handlers/chatCore/attemptLogging.ts
index 3192ddbd9b..f1ddcc1678 100644
--- a/open-sse/handlers/chatCore/attemptLogging.ts
+++ b/open-sse/handlers/chatCore/attemptLogging.ts
@@ -359,7 +359,6 @@ export function persistAttemptLogs(args: PersistAttemptLogsArgs, ctx: PersistAtt
     skillRequestId,
     detailedLoggingEnabled,
     reqLogger,
-    pendingRequestId,
     clientRawRequest,
     requestedModel,
     credentials,
@@ -458,8 +457,11 @@ export function persistAttemptLogs(args: PersistAttemptLogsArgs, ctx: PersistAtt
     }
   }
 
+  // #13481: each combo attempt needs its own row. Attempts share pendingRequestId, so
+  // keying the log on it made the successful member's insert hit the UNIQUE constraint
+  // and vanish from the dashboard; traceId is per attempt and pairs with request.started.
   saveCallLog({
-    id: pendingRequestId,
+    id: traceId,
     method: "POST",
     path: clientRawRequest?.endpoint || "/v1/chat/completions",
     status,
diff --git a/tests/unit/chatcore-attempt-logging.test.ts b/tests/unit/chatcore-attempt-logging.test.ts
index 2af6bbd41c..785409c93d 100644
--- a/tests/unit/chatcore-attempt-logging.test.ts
+++ b/tests/unit/chatcore-attempt-logging.test.ts
@@ -28,7 +28,11 @@ type CodexRotationEnvelope = {
 };
 
 function baseCtx(overrides: Record<string, unknown> = {}) {
+  // #13481: traceId defaults to pendingRequestId so existing tests (which poll
+  // by pendingRequestId) continue to work. Combo tests set both explicitly.
+  const pendingRequestId = (overrides.pendingRequestId as string) ?? "REPLACE";
   return {
+    traceId: overrides.traceId ?? pendingRequestId,
     provider: "openai",
     connectionId: "conn-1",
     model: "gpt-x",
@@ -195,3 +199,40 @@ test("unique tool_calls do not write provider.spec_violation audit", () => {
   });
   assert.equal(rows.length, 0);
 });
+
+// #13481: Combo attempts must use traceId as the log id, not pendingRequestId.
+// When a combo fails over, each attempt has a unique traceId but shares the
+// same pendingRequestId. Using pendingRequestId as the log id caused a UNIQUE
+// constraint violation — only the first (failed) attempt was logged.
+test("combo attempt uses traceId as the log id, not pendingRequestId", async () => {
+  const traceId = "combo-trace-attempt-2";
+  const pendingRequestId = "combo-shared-request-id";
+  persistAttemptLogs(
+    { status: 200, tokens: { input: 10, output: 20 } },
+    baseCtx({
+      traceId,
+      pendingRequestId,
+      comboName: "my-combo",
+      comboStepId: "my-combo-model-2",
+    })
+  );
+  const row = await pollForCallLog(traceId);
+  assert.ok(row, "call log row should be persisted with traceId as id");
+  assert.equal(row.status, 200);
+  assert.equal(row.comboStepId, "my-combo-model-2");
+
+  // A second attempt with the same pendingRequestId but different traceId
+  const traceId2 = "combo-trace-attempt-3";
+  persistAttemptLogs(
+    { status: 200, tokens: { input: 30, output: 40 } },
+    baseCtx({
+      traceId: traceId2,
+      pendingRequestId,
+      comboName: "my-combo",
+      comboStepId: "my-combo-model-3",
+    })
+  );
+  const row2 = await pollForCallLog(traceId2);
+  assert.ok(row2, "second combo attempt should also be persisted");
+  assert.equal(row2.comboStepId, "my-combo-model-3");
+});