fix(gateway): preserve stop reason for deferred agent aborts

src/gateway/chat-abort.ts

@@ -14,6 +14,7 @@ export type ChatAbortControllerEntry = {
   ownerDeviceId?: string;
   providerId?: string;
   authProviderId?: string;
+  abortStopReason?: string;
   /**
    * Which RPC owns this registration. Absent (undefined) is treated as
    * `"chat-send"` so pre-existing callers that constructed entries without
@@ -186,6 +187,9 @@ export function abortChatRunById(
   const bufferedText = ops.chatRunBuffers.get(runId);
   const partialText = bufferedText && bufferedText.trim() ? bufferedText : undefined;
   ops.chatAbortedRuns.set(runId, Date.now());
+  if (stopReason) {
+    active.abortStopReason = stopReason;
+  }
   active.controller.abort();
   ops.chatAbortControllers.delete(runId);
   ops.chatRunBuffers.delete(runId);

src/gateway/server-methods/agent.test.ts

@@ -3696,6 +3696,69 @@ describe("gateway agent handler chat.abort integration", () => {
     });
   });
 
+  it("preserves stop-command reason when /stop lands during the accepted ack yield", async () => {
+    prime();
+    mocks.agentCommand.mockReturnValueOnce(new Promise(() => {}));
+
+    const context = makeContext();
+    const respond = vi.fn();
+    const runId = "idem-stop-before-dispatch";
+    await invokeAgent(
+      {
+        message: "hi",
+        agentId: "main",
+        sessionKey: "agent:main:main",
+        idempotencyKey: runId,
+      },
+      { context, respond, reqId: runId, flushDispatch: false },
+    );
+
+    expectRecordFields(mockCallArg(respond, 0, 1), {
+      runId,
+      sessionKey: "agent:main:main",
+      status: "accepted",
+    });
+    expect(context.chatAbortControllers.has(runId)).toBe(true);
+
+    const stopRespond = vi.fn();
+    await chatHandlers["chat.send"]({
+      params: {
+        sessionKey: "agent:main:main",
+        message: "/stop",
+        idempotencyKey: "idem-stop-command-before-dispatch",
+      },
+      respond: stopRespond as never,
+      context,
+      req: { type: "req", id: "stop-req", method: "chat.send" },
+      client: null,
+      isWebchatConnect: () => false,
+    });
+
+    expectRecordFields(mockCallArg(stopRespond, 0, 1), {
+      aborted: true,
+      runIds: [runId],
+    });
+    expect(context.chatAbortControllers.has(runId)).toBe(false);
+
+    await flushScheduledDispatchStep();
+
+    expect(mocks.agentCommand).not.toHaveBeenCalled();
+    expectRecordFields(context.dedupe.get(`agent:${runId}`)?.payload, {
+      runId,
+      status: "timeout",
+      summary: "aborted",
+      stopReason: "stop",
+    });
+    const finalResponse = respond.mock.calls.find(
+      (call: unknown[]) => (call[1] as { status?: unknown } | undefined)?.status === "timeout",
+    );
+    expectRecordFields(requireValue(finalResponse, "terminal response missing")[1], {
+      runId,
+      status: "timeout",
+      stopReason: "stop",
+    });
+  });
+
   it("does not dispatch when chat.abort lands during pre-accept setup", async () => {
     prime();
     const requestedSessionKey = "agent:main:legacy-main";

src/gateway/server-methods/agent.ts

@@ -100,6 +100,7 @@ import {
 } from "../../utils/message-channel.js";
 import { resolveAssistantIdentity } from "../assistant-identity.js";
 import {
+  type ChatAbortControllerEntry,
   registerChatAbortController,
   resolveAgentRunExpiresAtMs,
   updateChatRunProvider,
@@ -547,6 +548,10 @@ function setAbortedAgentDedupeEntries(params: {
   });
 }
 
+function resolveAbortedAgentStopReason(entry?: ChatAbortControllerEntry): string {
+  return entry?.abortStopReason?.trim() || "rpc";
+}
+
 function deleteGatewayDedupeEntries(params: {
   dedupe: GatewayRequestContext["dedupe"];
   keys: readonly string[];
@@ -1669,11 +1674,12 @@ export const agentHandlers: GatewayRequestHandlers = {
         let dispatched = false;
         try {
           if (activeRunAbort.controller.signal.aborted) {
+            const stopReason = resolveAbortedAgentStopReason(activeRunAbort.entry);
             setAbortedAgentDedupeEntries({
               dedupe: context.dedupe,
               keys: agentDedupeKeys,
               runId,
-              stopReason: "rpc",
+              stopReason,
             });
             respond(
               true,
@@ -1681,7 +1687,7 @@ export const agentHandlers: GatewayRequestHandlers = {
                 runId,
                 status: "timeout" as const,
                 summary: "aborted",
-                stopReason: "rpc",
+                stopReason,
               },
               undefined,
               { runId },