fix: retire cancelled extension UI requests

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## [Unreleased]
 
+- Fixed daemon-aborted extension dialogs remaining live in the interactive client and sending a stale response after another client had already decided the request.
 - Fixed fullscreen wheel scrolling in Ghostty while retaining application link clicks; set `terminal.fullscreenMouse` to `false` to use native Cmd-click instead.
 - Changed the agents view to sort idle and inactive sessions by last message time, newest first, while keeping running agents in stable creation order.
 - Fixed `openai-codex` models being invisible to `rlm` subagents and `find_models` because model discovery reported Prime Agent's own version as the Codex client version ([#1375](https://github.com/PrimeIntellect-ai/prime-agent/pull/1375) by [@bilelrais](https://github.com/bilelrais)).

packages/coding-agent/docs/agent-connection.md

@@ -80,7 +80,7 @@ An initial or replacement snapshot combines:
 - active RLM child snapshots; and
 - an in-progress assistant message when one exists.
 
-Connection events cover session events, replacement and resynchronization snapshots, extension UI requests, connection status, and terminal closure. The adapter updates its cache before notifying the UI.
+Connection events cover session events, replacement and resynchronization snapshots, extension UI requests and exact-request cancellations, connection status, and terminal closure. The adapter updates its cache before notifying the UI.
 
 Some connection types still reuse internal `AgentMessage`, `AgentEvent`, and model types. Those are local TypeScript contracts, not promises of a stable public network schema.
 
@@ -116,7 +116,7 @@ When switching to a session already owned by another resident worker, a non-owne
 
 ## Extension UI Boundary
 
-Daemon-owned extensions can request serializable UI operations such as select, confirm, input, editor, notification, status, widget, title, and editor-text updates. The client validates the payload and returns a serializable response.
+Daemon-owned extensions can request serializable UI operations such as select, confirm, input, editor, notification, status, widget, title, and editor-text updates. The client validates the payload and returns a serializable response. If the daemon aborts or times out a pending dialog, it sends a capability-gated cancellation for that exact request ID; the interactive client retires only that request without sending a response.
 
 Executable callbacks are deliberately excluded:
 

packages/coding-agent/src/modes/agent-connection/daemon-agent-connection.ts

@@ -305,7 +305,7 @@ export class DaemonAgentConnection implements AgentConnection {
 			capabilities: [
 				"attach_snapshot",
 				"event_sequence",
-				...(supportsExtensionUi ? (["extension_ui"] as const) : []),
+				...(supportsExtensionUi ? (["extension_ui", "extension_ui_cancellation"] as const) : []),
 				"slim_attach",
 				"chunked_snapshot",
 				...(this.options.ownedSession ? (["client_owned_sessions"] as const) : []),
@@ -1156,7 +1156,7 @@ export class DaemonAgentConnection implements AgentConnection {
 				capabilities: [
 					"attach_snapshot",
 					"event_sequence",
-					...(supportsExtensionUi ? (["extension_ui"] as const) : []),
+					...(supportsExtensionUi ? (["extension_ui", "extension_ui_cancellation"] as const) : []),
 					"slim_attach",
 					"chunked_snapshot",
 					...(this.options.ownedSession ? (["client_owned_sessions"] as const) : []),
@@ -1555,6 +1555,10 @@ export class DaemonAgentConnection implements AgentConnection {
 			});
 			return;
 		}
+		if (message.type === "extension_ui_cancelled") {
+			await this.emit({ type: "extension_ui_cancelled", requestId: message.id });
+			return;
+		}
 		if (message.type === "extension_error") {
 			await this.emit({
 				type: "extension_error",

packages/coding-agent/src/modes/agent-connection/types.ts

@@ -624,6 +624,7 @@ export type AgentConnectionEvent =
 	| { type: "session_resynced"; snapshot: AgentConnectionSnapshot }
 	| { type: "session_status"; recap?: string }
 	| { type: "extension_ui_request"; request: AgentConnectionExtensionUiRequest }
+	| { type: "extension_ui_cancelled"; requestId: string }
 	| { type: "extension_error"; extensionPath: string; event: string; error: string }
 	| { type: "connection_status"; status: "reconnecting" | "connected"; error?: string }
 	| { type: "heartbeats_changed" }

packages/coding-agent/src/modes/daemon/daemon-extension-binding.ts

@@ -159,7 +159,13 @@ function createExtensionUIContext(
 					clearTimeout(timeoutId);
 				}
 				opts?.signal?.removeEventListener("abort", onAbort);
-				state.extensionUiRequests.delete(requestId);
+				if (state.extensionUiRequests.delete(requestId)) {
+					broadcast(state, {
+						type: "extension_ui_cancelled",
+						activeSessionId: state.activeSessionId,
+						id: requestId,
+					});
+				}
 			};
 			const finish = (value: T) => {
 				cleanup();

packages/coding-agent/src/modes/daemon/daemon-mode.ts

@@ -6888,6 +6888,7 @@ type SequencedDaemonOutbound = Extract<
 			| "session_resynced"
 			| "session_closed"
 			| "extension_ui_request"
+			| "extension_ui_cancelled"
 			| "extension_error";
 	}
 >;
@@ -6900,11 +6901,15 @@ function isSequencedSessionOutbound(message: DaemonOutbound): message is Sequenc
 		message.type === "session_resynced" ||
 		message.type === "session_closed" ||
 		message.type === "extension_ui_request" ||
+		message.type === "extension_ui_cancelled" ||
 		message.type === "extension_error"
 	);
 }
 
 export function shouldSendDaemonOutboundToClient(client: DaemonSocketClient, message: DaemonOutbound): boolean {
+	if (message.type === "extension_ui_cancelled") {
+		return daemonClientCapabilitiesForSession(client, message.activeSessionId).has("extension_ui_cancellation");
+	}
 	return (
 		message.type !== "extension_ui_request" ||
 		!isDaemonDialogExtensionUiRequest(message.method) ||

packages/coding-agent/src/modes/daemon/daemon-protocol.ts

@@ -60,8 +60,9 @@ export const DAEMON_COMMAND_ENVELOPE_MIN_PROTOCOL_VERSION = 7;
 // Revision 14 carries the client's monotonic telemetry opt-out on attach and reattach.
 // Revision 15 adds the mutate_queued_message command and queue_message_mutation capability.
 // Revision 16 adds the "stopping" workerState and stops reporting disconnected workers as "ready".
-export const DAEMON_SCHEMA_REVISION = 16;
-export const DAEMON_SCHEMA_ID = "protocol-7-schema-16-1bcb9e7f1a49";
+// Revision 17 adds capability-gated exact-request extension UI cancellation.
+export const DAEMON_SCHEMA_REVISION = 17;
+export const DAEMON_SCHEMA_ID = "protocol-7-schema-17-28439aeb8512";
 
 export type DaemonProtocolName = typeof DAEMON_PROTOCOL_NAME;
 export type DaemonProtocolVersion = number;
@@ -77,6 +78,7 @@ export type DaemonClientCapability =
 	| "attach_snapshot"
 	| "event_sequence"
 	| "extension_ui"
+	| "extension_ui_cancellation"
 	| "slim_attach"
 	| "chunked_snapshot"
 	| "client_owned_sessions";
@@ -123,6 +125,7 @@ export const DAEMON_SUPPORTED_CLIENT_CAPABILITIES: readonly DaemonClientCapabili
 	"attach_snapshot",
 	"event_sequence",
 	"extension_ui",
+	"extension_ui_cancellation",
 	"slim_attach",
 	"chunked_snapshot",
 	"client_owned_sessions",
@@ -938,6 +941,7 @@ export type DaemonOutbound =
 			payload: Record<string, unknown>;
 			meta?: DaemonEventMeta;
 	  }
+	| { type: "extension_ui_cancelled"; activeSessionId: string; id: string; meta?: DaemonEventMeta }
 	| {
 			type: "extension_error";
 			activeSessionId: string;
@@ -967,6 +971,11 @@ export const DAEMON_OUTBOUND_COMPATIBILITY = {
 	session_detached: LEGACY_DAEMON_COMMAND,
 	session_closed: LEGACY_DAEMON_COMMAND,
 	extension_ui_request: LEGACY_DAEMON_COMMAND,
+	extension_ui_cancelled: {
+		minProtocol: 7,
+		minSchemaRevision: 17,
+		capability: "extension_ui_cancellation",
+	},
 	extension_error: LEGACY_DAEMON_COMMAND,
 } as const satisfies Record<DaemonOutbound["type"], DaemonCommandCompatibility>;
 

packages/coding-agent/src/modes/daemon/daemon-supervisor.ts

@@ -2422,15 +2422,24 @@ export class DaemonSupervisor {
 		if (!worker.client) {
 			throw new Error("Session worker is not connected");
 		}
-		const supportsExtensionUi = [...this.clients].some(
-			(client) => client.attachedActiveSessionIds.has(activeSessionId) && client.supportsExtensionUi,
+		const attachedClients = [...this.clients].filter((client) =>
+			client.attachedActiveSessionIds.has(activeSessionId),
+		);
+		const supportsExtensionUi = attachedClients.some((client) => client.supportsExtensionUi);
+		const supportsExtensionUiCancellation = attachedClients.some(
+			(client) => client.supportsExtensionUi && client.capabilities.has("extension_ui_cancellation"),
 		);
 		const response = await worker.client.requestWorker({
 			type: "worker_subscribe",
 			activeSessionId,
-			capabilities: supportsExtensionUi
-				? ["attach_snapshot", "event_sequence", "extension_ui", "slim_attach", "chunked_snapshot"]
-				: ["attach_snapshot", "event_sequence", "slim_attach", "chunked_snapshot"],
+			capabilities: [
+				"attach_snapshot",
+				"event_sequence",
+				...(supportsExtensionUi ? (["extension_ui"] as const) : []),
+				...(supportsExtensionUiCancellation ? (["extension_ui_cancellation"] as const) : []),
+				"slim_attach",
+				"chunked_snapshot",
+			],
 			supportsExtensionUi,
 		});
 		if (!response.success) {
@@ -4257,6 +4266,9 @@ export class DaemonSupervisor {
 			if (outboundType === "extension_ui_request" && !client.supportsExtensionUi) {
 				continue;
 			}
+			if (outboundType === "extension_ui_cancelled" && !client.capabilities.has("extension_ui_cancellation")) {
+				continue;
+			}
 			if (client.snapshotActiveSessionIds?.has(activeSessionId)) {
 				this.queueCatchup(client, activeSessionId, outboundType === "session_replaced" ? "replacement" : "resync");
 				continue;

packages/coding-agent/src/modes/interactive/interactive-mode.ts

@@ -3906,18 +3906,35 @@ export class InteractiveMode {
 	/**
 	 * Show a multi-line editor for extensions (with Ctrl+G support).
 	 */
-	private showExtensionEditor(title: string, prefill?: string): Promise<string | undefined> {
+	private showExtensionEditor(
+		title: string,
+		prefill?: string,
+		opts?: ExtensionUIDialogOptions,
+	): Promise<string | undefined> {
 		return new Promise((resolve) => {
+			if (opts?.signal?.aborted) {
+				resolve(undefined);
+				return;
+			}
+
+			const onAbort = () => {
+				this.hideExtensionEditor();
+				resolve(undefined);
+			};
+			opts?.signal?.addEventListener("abort", onAbort, { once: true });
+
 			this.extensionEditor = new ExtensionEditorComponent(
 				this.ui,
 				this.keybindings,
 				title,
 				prefill,
 				(value) => {
+					opts?.signal?.removeEventListener("abort", onAbort);
 					this.hideExtensionEditor();
 					resolve(value);
 				},
 				() => {
+					opts?.signal?.removeEventListener("abort", onAbort);
 					this.hideExtensionEditor();
 					resolve(undefined);
 				},
@@ -5135,6 +5152,8 @@ export class InteractiveMode {
 					this.handleSideQuestionEvent(event.event);
 				} else if (event.type === "extension_ui_request") {
 					await this.handleConnectionExtensionUiRequest(event.request);
+				} else if (event.type === "extension_ui_cancelled") {
+					this.cancelConnectionExtensionUiRequest(event.requestId);
 				} else if (event.type === "connection_status") {
 					this.showStatus(
 						event.status === "connected" ? "Daemon reconnected" : "Daemon connection lost; reconnecting…",
@@ -5160,14 +5179,21 @@ export class InteractiveMode {
 
 		try {
 			if (expectsResponse) {
+				const dialogController = new AbortController();
 				let cancelLocal: (response: AgentConnectionExtensionUiResponse) => void = () => {};
 				const cancelled = new Promise<AgentConnectionExtensionUiResponse>((resolve) => {
 					cancelLocal = resolve;
 				});
 				this.activeConnectionExtensionUiRequests.set(request.id, {
-					cancelLocal: () => cancelLocal({ cancelled: true }),
+					cancelLocal: () => {
+						dialogController.abort();
+						cancelLocal({ cancelled: true });
+					},
 				});
-				response = await Promise.race([this.resolveConnectionExtensionUiRequest(request), cancelled]);
+				response = await Promise.race([
+					this.resolveConnectionExtensionUiRequest(request, dialogController.signal),
+					cancelled,
+				]);
 			} else {
 				response = await this.resolveConnectionExtensionUiRequest(request);
 			}
@@ -5201,6 +5227,15 @@ export class InteractiveMode {
 		);
 	}
 
+	private cancelConnectionExtensionUiRequest(requestId: string): void {
+		const request = this.activeConnectionExtensionUiRequests.get(requestId);
+		if (!request) {
+			return;
+		}
+		this.activeConnectionExtensionUiRequests.delete(requestId);
+		request.cancelLocal();
+	}
+
 	private cancelActiveConnectionExtensionUiRequests(): void {
 		const requestIds = [...this.activeConnectionExtensionUiRequests.keys()];
 		for (const requestId of requestIds) {
@@ -5218,6 +5253,7 @@ export class InteractiveMode {
 
 	private async resolveConnectionExtensionUiRequest(
 		request: AgentConnectionExtensionUiRequest,
+		signal?: AbortSignal,
 	): Promise<AgentConnectionExtensionUiResponse | undefined> {
 		const { payload } = request;
 		switch (request.method) {
@@ -5229,6 +5265,7 @@ export class InteractiveMode {
 				}
 				const value = await this.showExtensionSelector(title, options, {
 					timeout: getPayloadNumber(payload, "timeout"),
+					signal,
 				});
 				return value === undefined ? { cancelled: true } : { value };
 			}
@@ -5240,6 +5277,7 @@ export class InteractiveMode {
 				}
 				const confirmed = await this.showExtensionConfirm(title, message, {
 					timeout: getPayloadNumber(payload, "timeout"),
+					signal,
 				});
 				return { confirmed };
 			}
@@ -5250,6 +5288,7 @@ export class InteractiveMode {
 				}
 				const value = await this.showExtensionInput(title, getPayloadString(payload, "placeholder"), {
 					timeout: getPayloadNumber(payload, "timeout"),
+					signal,
 				});
 				return value === undefined ? { cancelled: true } : { value };
 			}
@@ -5258,7 +5297,7 @@ export class InteractiveMode {
 				if (!title) {
 					return { cancelled: true };
 				}
-				const value = await this.showExtensionEditor(title, getPayloadString(payload, "prefill"));
+				const value = await this.showExtensionEditor(title, getPayloadString(payload, "prefill"), { signal });
 				return value === undefined ? { cancelled: true } : { value };
 			}
 			case "notify": {