fix: expose abort signal to extensions closes #2660

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

@@ -2219,6 +2219,7 @@ export class AgentSession {
 			{
 				getModel: () => this.model,
 				isIdle: () => !this.isStreaming,
+				getSignal: () => this.agent.signal,
 				abort: () => this.abort(),
 				hasPendingMessages: () => this.pendingMessageCount > 0,
 				shutdown: () => {

packages/coding-agent/src/core/extensions/runner.ts

@@ -208,6 +208,7 @@ export class ExtensionRunner {
 	private errorListeners: Set<ExtensionErrorListener> = new Set();
 	private getModel: () => Model<any> | undefined = () => undefined;
 	private isIdleFn: () => boolean = () => true;
+	private getSignalFn: () => AbortSignal | undefined = () => undefined;
 	private waitForIdleFn: () => Promise<void> = async () => {};
 	private abortFn: () => void = () => {};
 	private hasPendingMessagesFn: () => boolean = () => false;
@@ -265,6 +266,7 @@ export class ExtensionRunner {
 		// Context actions (required)
 		this.getModel = contextActions.getModel;
 		this.isIdleFn = contextActions.isIdle;
+		this.getSignalFn = contextActions.getSignal;
 		this.abortFn = contextActions.abort;
 		this.hasPendingMessagesFn = contextActions.hasPendingMessages;
 		this.shutdownHandler = contextActions.shutdown;
@@ -541,6 +543,7 @@ export class ExtensionRunner {
 				return getModel();
 			},
 			isIdle: () => this.isIdleFn(),
+			signal: this.getSignalFn(),
 			abort: () => this.abortFn(),
 			hasPendingMessages: () => this.hasPendingMessagesFn(),
 			shutdown: () => this.shutdownHandler(),

packages/coding-agent/src/core/extensions/types.ts

@@ -274,6 +274,8 @@ export interface ExtensionContext {
 	model: Model<any> | undefined;
 	/** Whether the agent is idle (not streaming) */
 	isIdle(): boolean;
+	/** The current abort signal, or undefined when the agent is not streaming. */
+	signal: AbortSignal | undefined;
 	/** Abort the current agent operation */
 	abort(): void;
 	/** Whether there are queued messages waiting */
@@ -1391,6 +1393,7 @@ export interface ExtensionActions {
 export interface ExtensionContextActions {
 	getModel: () => Model<any> | undefined;
 	isIdle: () => boolean;
+	getSignal: () => AbortSignal | undefined;
 	abort: () => void;
 	hasPendingMessages: () => boolean;
 	shutdown: () => void;