diff --git a/src/auto-reply/reply/dispatch-acp.test.ts b/src/auto-reply/reply/dispatch-acp.test.ts
index 57d18cb8693..708d6a894f5 100644
--- a/src/auto-reply/reply/dispatch-acp.test.ts
+++ b/src/auto-reply/reply/dispatch-acp.test.ts
@@ -471,6 +471,31 @@ describe("tryDispatchAcpReply", () => {
     expect(dispatcher.sendBlockReply).not.toHaveBeenCalled();
   });
 
+  it("keeps same-provider tool-only ACP final replies private when an origin route exists", async () => {
+    setReadyAcpResolution();
+    mockVisibleTextTurn("hidden final");
+    const onReplyStart = vi.fn();
+    const { dispatcher } = createDispatcher();
+
+    const result = await runDispatch({
+      bodyForAgent: "reply via message tool if needed",
+      dispatcher,
+      onReplyStart,
+      suppressUserDelivery: true,
+      suppressReplyLifecycle: false,
+      sourceReplyDeliveryMode: "message_tool_only",
+      shouldRouteToOriginating: true,
+      originatingChannel: "discord",
+      originatingTo: "channel:C1",
+    });
+
+    expect(result?.queuedFinal).toBe(false);
+    expect(onReplyStart).toHaveBeenCalledTimes(1);
+    expect(routeMocks.routeReply).not.toHaveBeenCalled();
+    expect(dispatcher.sendFinalReply).not.toHaveBeenCalled();
+    expect(dispatcher.sendBlockReply).not.toHaveBeenCalled();
+  });
+
   it("edits ACP tool lifecycle updates in place when supported", async () => {
     setReadyAcpResolution();
     mockToolLifecycleTurn("call-1");
diff --git a/src/auto-reply/reply/dispatch-from-config.test.ts b/src/auto-reply/reply/dispatch-from-config.test.ts
index d47d22a170e..55a97bd7955 100644
--- a/src/auto-reply/reply/dispatch-from-config.test.ts
+++ b/src/auto-reply/reply/dispatch-from-config.test.ts
@@ -4502,6 +4502,35 @@ describe("sendPolicy deny — suppress delivery, not processing (#53328)", () =>
     expect(dispatcher.sendFinalReply).not.toHaveBeenCalled();
   });
 
+  it("does not auto-route same-provider group/channel final replies in message-tool-only mode", async () => {
+    setNoAbort();
+    mocks.routeReply.mockClear();
+    const dispatcher = createDispatcher();
+    const replyResolver = vi.fn(async (_ctx: MsgContext, opts?: GetReplyOptions) => {
+      expect(opts?.sourceReplyDeliveryMode).toBe("message_tool_only");
+      return { text: "final reply" } satisfies ReplyPayload;
+    });
+
+    const result = await dispatchReplyFromConfig({
+      ctx: buildTestCtx({
+        ChatType: "channel",
+        Provider: "discord",
+        Surface: "discord",
+        OriginatingChannel: "discord",
+        OriginatingTo: "channel:C1",
+        SessionKey: "test:discord:channel:C1",
+      }),
+      cfg: emptyConfig,
+      dispatcher,
+      replyResolver,
+    });
+
+    expect(replyResolver).toHaveBeenCalledTimes(1);
+    expect(result.queuedFinal).toBe(false);
+    expect(dispatcher.sendFinalReply).not.toHaveBeenCalled();
+    expect(mocks.routeReply).not.toHaveBeenCalled();
+  });
+
   it("uses harness defaults for direct source delivery when config is unset", async () => {
     setNoAbort();
     registerAgentHarness({