fix(gateway): preserve timeout abort stop reason

steipete · steipete · commit f2a46a31af2e · 2026-05-27T03:32:20.000+01:00
diff --git a/src/gateway/server-methods/agent.test.ts b/src/gateway/server-methods/agent.test.ts
@@ -2720,6 +2720,7 @@ describe("gateway agent handler", () => {
             runId: "task-registry-agent-run-abort-error",
             status: "timeout",
             summary: "aborted",
+            stopReason: "rpc",
           },
         );
       });
@@ -2762,6 +2763,7 @@ describe("gateway agent handler", () => {
             runId: "task-registry-agent-run-timeout-error",
             status: "timeout",
             summary: "aborted",
+            stopReason: "timeout",
           },
         );
       });
@@ -2808,6 +2810,7 @@ describe("gateway agent handler", () => {
               runId: "task-registry-agent-run-wrapped-timeout-error",
               status: "timeout",
               summary: "aborted",
+              stopReason: "timeout",
             },
           );
           expect(
diff --git a/src/gateway/server-methods/agent.ts b/src/gateway/server-methods/agent.ts
@@ -631,6 +631,10 @@ function isGatewayAgentAbortRejection(error: unknown, signal: AbortSignal): bool
   return isAbortError(error) || readErrorName(error) === "TimeoutError";
 }
 
+function resolveGatewayAgentAbortStopReason(signal: AbortSignal): "rpc" | "timeout" {
+  return readErrorName(signal.reason) === "TimeoutError" ? "timeout" : "rpc";
+}
+
 function resolveAbortedAgentStopReason(entry?: ChatAbortControllerEntry): string {
   return entry?.abortStopReason?.trim() || "rpc";
 }
@@ -732,11 +736,12 @@ function dispatchAgentRunFromGateway(params: {
         });
       }
       const error = errorShape(ErrorCodes.UNAVAILABLE, renderedErr);
+      const stopReason = resolveGatewayAgentAbortStopReason(params.abortController.signal);
       const payload = {
         runId: params.runId,
         status: aborted ? ("timeout" as const) : ("error" as const),
         summary: aborted ? "aborted" : renderedErr,
-        ...(aborted ? { stopReason: "rpc", timeoutPhase: "gateway_draining" as const } : {}),
+        ...(aborted ? { stopReason, timeoutPhase: "gateway_draining" as const } : {}),
       };
       setGatewayDedupeEntries({
         dedupe: params.context.dedupe,
