fix(agents): fail closed missing requester completion routes

CHANGELOG.md

@@ -39,6 +39,7 @@ Docs: https://docs.openclaw.ai
 - Channels/message tool: surface Discord, Slack, and Mattermost `user:`/`channel:` target syntax in the shared message target schema and Discord ambiguity errors, so DM sends by numeric id stop burning retries before finding `user:<id>`. Fixes #72401. Thanks @garyd9, @hclsys, and @praveen9354.
 - Agents/tools: scope tool-loop detection history to the active run when available, so scheduled heartbeat cycles no longer inherit stale repeated-call counts from previous runs. Fixes #40144. Thanks @mattbrown319.
 - Agents/subagents: preserve requester delivery for completion announces when a child agent is bound to a different channel account while keeping same-channel thread completions routed to the child thread. Thanks @sfuminya.
+- Agents/subagents: fail closed instead of selecting a single child thread binding when completion delivery lacks requester conversation signal. Thanks @suyua9.
 - Control UI: show loading, reload, and retry states when a lazy dashboard panel cannot load after an upgrade, so the Logs tab no longer appears blank on stale browser bundles. Fixes #72450. Thanks @sobergou.
 - Gateway/plugins: start the Gateway in degraded mode when a single plugin entry has invalid schema config, and let `openclaw doctor --fix` quarantine that plugin config instead of crash-looping every channel. Fixes #62976 and #70371. Thanks @Doraemon-Claw and @pksidekyk.
 - Agents/plugins: skip malformed plugin tools with missing schema objects and report plugin diagnostics, so one broken tool no longer crashes Anthropic agent runs. Fixes #69423. Thanks @jmnickels.

src/agents/subagent-announce.format.e2e.test.ts

@@ -985,6 +985,62 @@ describe("subagent announce formatting", () => {
     expect(call?.params?.to).toBe("channel:thread-bound-1");
   });
 
+  it("does not use a child bound destination when completion requester conversation is missing", async () => {
+    sessionStore = {
+      "agent:main:subagent:test": {
+        sessionId: "child-session-bound-missing-requester",
+      },
+      "agent:main:main": {
+        sessionId: "requester-session-bound-missing-requester",
+      },
+    };
+    chatHistoryMock.mockResolvedValueOnce({
+      messages: [{ role: "assistant", content: [{ type: "text", text: "bound answer: 2" }] }],
+    });
+    registerSessionBindingAdapter({
+      channel: "discord",
+      accountId: "acct-1",
+      listBySession: (targetSessionKey: string) =>
+        targetSessionKey === "agent:main:subagent:test"
+          ? [
+              {
+                bindingId: "discord:acct-1:thread-bound-1",
+                targetSessionKey,
+                targetKind: "subagent",
+                conversation: {
+                  channel: "discord",
+                  accountId: "acct-1",
+                  conversationId: "thread-bound-1",
+                  parentConversationId: "parent-main",
+                },
+                status: "active",
+                boundAt: Date.now(),
+              },
+            ]
+          : [],
+      resolveByConversation: () => null,
+    });
+
+    const didAnnounce = await runSubagentAnnounceFlow({
+      childSessionKey: "agent:main:subagent:test",
+      childRunId: "run-session-bound-missing-requester",
+      requesterSessionKey: "agent:main:main",
+      requesterDisplayKey: "main",
+      requesterOrigin: { channel: "discord", accountId: "acct-1" },
+      ...defaultOutcomeAnnounce,
+      expectsCompletionMessage: true,
+      spawnMode: "session",
+    });
+
+    expect(didAnnounce).toBe(true);
+    expect(sendSpy).not.toHaveBeenCalled();
+    expect(agentSpy).toHaveBeenCalledTimes(1);
+    const call = agentSpy.mock.calls[0]?.[0] as { params?: Record<string, unknown> };
+    expect(call?.params?.deliver).toBe(false);
+    expect(call?.params?.to).toBeUndefined();
+    expect(call?.params?.threadId).toBeUndefined();
+  });
+
   it("does not duplicate to main channel when two active bound sessions complete from the same requester channel", async () => {
     sessionStore = {
       "agent:main:subagent:child-a": {

src/infra/outbound/bound-delivery-router.test.ts

@@ -105,7 +105,17 @@ describe("bound delivery router", () => {
       expected: {
         binding: null,
         mode: "fallback",
-        reason: "ambiguous-without-requester",
+        reason: "missing-requester",
+      },
+    },
+    {
+      name: "fails closed when requester signal is missing even with a single binding",
+      bindings: [createRuntimeBinding(TARGET_SESSION_KEY, "thread-1", 1)],
+      failClosed: true,
+      expected: {
+        binding: null,
+        mode: "fallback",
+        reason: "missing-requester",
       },
     },
     {

src/infra/outbound/bound-delivery-router.ts

@@ -79,6 +79,13 @@ export function createBoundDeliveryRouter(
       }
 
       if (!input.requester) {
+        if (input.failClosed) {
+          return {
+            binding: null,
+            mode: "fallback",
+            reason: "missing-requester",
+          };
+        }
         if (activeBindings.length === 1) {
           return {
             binding: activeBindings[0] ?? null,