fix(vibe): deferred IRC wakes during mode exit

packages/coding-agent/src/session/agent-session.ts

@@ -776,7 +776,14 @@ export class AgentSession {
 	 *  the agent responds to the peer. Skip only when a queued steer/follow-up will itself drive a
 	 *  resume turn whose aside poll already consumes these (no double-wake). */
 	#resumeStrandedIrcAsides(): void {
-		if (this.#isDisposed || this.isStreaming || !this.#irc.hasPending()) return;
+		if (
+			this.#modeExitDrainSuppressionDepth > 0 ||
+			this.#isDisposed ||
+			this.isStreaming ||
+			!this.#irc.hasPending()
+		) {
+			return;
+		}
 		if (this.#canAutoContinueForFollowUp() && this.agent.hasQueuedMessages()) return;
 		const records = this.#irc.drainPending();
 		if (this.#planModeState?.enabled) {
@@ -805,6 +812,10 @@ export class AgentSession {
 	 *  because #canAutoContinueForFollowUp suppresses follow-up auto-resume while a user interrupt is
 	 *  in effect, even though the wake left a provider-valid tail. */
 	#wakeForIrc(records: CustomMessage[]): void {
+		if (this.#modeExitDrainSuppressionDepth > 0) {
+			this.#irc.deferWake(records);
+			return;
+		}
 		// Park only a *blocked* follow-up (one a user interrupt is intentionally holding); an
 		// already-resumable follow-up can ride the wake turn normally without reordering.
 		const parkedFollowUps =
@@ -5969,6 +5980,7 @@ export class AgentSession {
 			this.#modeExitDrainSuppressionDepth--;
 			if (this.#modeExitDrainSuppressionDepth === 0) {
 				this.#scheduleIdleQueueDrain();
+				this.#resumeStrandedIrcAsides();
 			}
 		}
 	}

packages/coding-agent/src/session/irc-bridge.ts

@@ -51,6 +51,11 @@ export class IrcBridge {
 		return records;
 	}
 
+	/** Queues records whose idle wake must wait for a session transition to finish. */
+	deferWake(records: CustomMessage[]): void {
+		this.#asides.push(...records);
+	}
+
 	/** Surfaces and consumes queued incoming records before automatic injection. */
 	drainInboxMessages(agentId: string, opts?: { from?: string; limit?: number }): IrcMessage[] {
 		const messages: IrcMessage[] = [];

packages/coding-agent/test/interactive-mode-vibe-toggle.test.ts

@@ -250,6 +250,64 @@ describe("InteractiveMode vibe mode toggle", () => {
 		expect(session.getToolByName("vibe_spawn")).toBeUndefined();
 	});
 
+	it("holds IRC wakes during Vibe teardown until the tools are removed", async () => {
+		const toolNamesPerCall: string[][] = [];
+		const firstStarted = Promise.withResolvers<void>();
+		streamFn = (_model, context, options) => {
+			toolNamesPerCall.push((context.tools ?? []).map(tool => tool.name));
+			const isFirst = toolNamesPerCall.length === 1;
+			const stream = new AssistantMessageEventStream();
+			queueMicrotask(() => {
+				stream.push({ type: "start", partial: createAssistantMessage("") });
+				if (isFirst) {
+					options?.signal?.addEventListener(
+						"abort",
+						() => stream.push({ type: "error", reason: "aborted", error: createAssistantMessage("Aborted") }),
+						{ once: true },
+					);
+					firstStarted.resolve();
+				} else {
+					stream.push({ type: "done", reason: "stop", message: createAssistantMessage("Resumed") });
+				}
+			});
+			return stream;
+		};
+
+		await mode.handleVibeModeCommand();
+		const prompt = session.prompt("Delegate this");
+		await firstStarted.promise;
+		await session.deliverIrcMessage({ id: "m1", from: "peer", to: "me", body: "first", ts: Date.now() });
+
+		const abortSettled = Promise.withResolvers<void>();
+		const releaseTeardown = Promise.withResolvers<void>();
+		const abort = session.abort.bind(session);
+		vi.spyOn(session, "abort").mockImplementation(async options => {
+			await abort(options);
+			abortSettled.resolve();
+			await releaseTeardown.promise;
+		});
+		const exit = mode.handleVibeModeCommand();
+		await abortSettled.promise;
+		await session.deliverIrcMessage({ id: "m2", from: "peer", to: "me", body: "second", ts: Date.now() });
+		for (let index = 0; index < 5; index++) await Promise.resolve();
+		expect(toolNamesPerCall).toHaveLength(1);
+		releaseTeardown.resolve();
+
+		await exit;
+		await prompt;
+		await session.waitForIdle();
+
+		expect(toolNamesPerCall).toHaveLength(2);
+		for (const name of VIBE_TOOL_NAMES) {
+			expect(toolNamesPerCall[1]).not.toContain(name);
+		}
+		expect(
+			session.agent.state.messages.filter(
+				message => message.role === "custom" && message.customType === "irc:incoming",
+			),
+		).toHaveLength(2);
+	});
+
 	it("keeps a same-named non-built-in Todo tool unavailable in Vibe mode", async () => {
 		const model = session.model;
 		if (!model) throw new Error("Expected active model");