fix(agent): stop tool preflight after extension abort

closes #4276

packages/agent/CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Fixed
 
+- Fixed tool-call preflight to stop preparing sibling tool calls after the run is aborted ([#4276](https://github.com/earendil-works/pi/issues/4276)).
 - Fixed tail truncation for oversized single-line output that ends with a trailing newline ([#4715](https://github.com/earendil-works/pi/issues/4715)).
 - Fixed Windows Node execution environment command spawns to hide helper console windows from background processes ([#4699](https://github.com/earendil-works/pi/issues/4699)).
 

packages/agent/src/agent-loop.ts

@@ -436,6 +436,10 @@ async function executeToolCallsSequential(
 		await emitToolResultMessage(toolResultMessage, emit);
 		finalizedCalls.push(finalized);
 		messages.push(toolResultMessage);
+
+		if (signal?.aborted) {
+			break;
+		}
 	}
 
 	return {
@@ -471,6 +475,9 @@ async function executeToolCallsParallel(
 			} satisfies FinalizedToolCallOutcome;
 			await emitToolExecutionEnd(finalized, emit);
 			finalizedCalls.push(finalized);
+			if (signal?.aborted) {
+				break;
+			}
 			continue;
 		}
 
@@ -487,6 +494,9 @@ async function executeToolCallsParallel(
 			await emitToolExecutionEnd(finalized, emit);
 			return finalized;
 		});
+		if (signal?.aborted) {
+			break;
+		}
 	}
 
 	const orderedFinalizedCalls = await Promise.all(
@@ -578,6 +588,13 @@ async function prepareToolCall(
 				},
 				signal,
 			);
+			if (signal?.aborted) {
+				return {
+					kind: "immediate",
+					result: createErrorToolResult("Operation aborted"),
+					isError: true,
+				};
+			}
 			if (beforeResult?.block) {
 				return {
 					kind: "immediate",
@@ -586,6 +603,13 @@ async function prepareToolCall(
 				};
 			}
 		}
+		if (signal?.aborted) {
+			return {
+				kind: "immediate",
+				result: createErrorToolResult("Operation aborted"),
+				isError: true,
+			};
+		}
 		return {
 			kind: "prepared",
 			toolCall,

packages/coding-agent/CHANGELOG.md

@@ -4,6 +4,7 @@
 
 ### Fixed
 
+- Fixed extension `ctx.abort()` during tool-call preflight to stop later confirmations and restore queued interactive input like Escape ([#4276](https://github.com/earendil-works/pi/issues/4276)).
 - Fixed AgentSession retry, compaction, and event settlement to use the awaited agent lifecycle instead of a separate event queue, and added `willRetry` to `agent_end` session events.
 - Fixed the subagent extension's parallel mode to return useful per-task output and failed-task diagnostics to the parent model instead of 100-character previews ([#4710](https://github.com/earendil-works/pi/issues/4710)).
 - Fixed Windows local bash execution to hide helper console windows when launched from background SDK processes ([#4699](https://github.com/earendil-works/pi/issues/4699)).

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

@@ -185,6 +185,7 @@ export interface AgentSessionConfig {
 export interface ExtensionBindings {
 	uiContext?: ExtensionUIContext;
 	commandContextActions?: ExtensionCommandContextActions;
+	abortHandler?: () => void;
 	shutdownHandler?: ShutdownHandler;
 	onError?: ExtensionErrorListener;
 }
@@ -296,6 +297,7 @@ export class AgentSession {
 	private _sessionStartEvent: SessionStartEvent;
 	private _extensionUIContext?: ExtensionUIContext;
 	private _extensionCommandContextActions?: ExtensionCommandContextActions;
+	private _extensionAbortHandler?: () => void;
 	private _extensionShutdownHandler?: ShutdownHandler;
 	private _extensionErrorListener?: ExtensionErrorListener;
 	private _extensionErrorUnsubscriber?: () => void;
@@ -2042,6 +2044,9 @@ export class AgentSession {
 		if (bindings.commandContextActions !== undefined) {
 			this._extensionCommandContextActions = bindings.commandContextActions;
 		}
+		if (bindings.abortHandler !== undefined) {
+			this._extensionAbortHandler = bindings.abortHandler;
+		}
 		if (bindings.shutdownHandler !== undefined) {
 			this._extensionShutdownHandler = bindings.shutdownHandler;
 		}
@@ -2206,7 +2211,13 @@ export class AgentSession {
 				getModel: () => this.model,
 				isIdle: () => !this.isStreaming,
 				getSignal: () => this.agent.signal,
-				abort: () => this.abort(),
+				abort: () => {
+					if (this._extensionAbortHandler) {
+						this._extensionAbortHandler();
+						return;
+					}
+					void this.abort();
+				},
 				hasPendingMessages: () => this.pendingMessageCount > 0,
 				shutdown: () => {
 					this._extensionShutdownHandler?.();

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

@@ -1478,6 +1478,9 @@ export class InteractiveMode {
 		const uiContext = this.createExtensionUIContext();
 		await this.session.bindExtensions({
 			uiContext,
+			abortHandler: () => {
+				this.restoreQueuedMessagesToEditor({ abort: true });
+			},
 			commandContextActions: {
 				waitForIdle: () => this.session.agent.waitForIdle(),
 				newSession: async (options) => {
@@ -1627,7 +1630,9 @@ export class InteractiveMode {
 			model: this.session.model,
 			isIdle: () => !this.session.isStreaming,
 			signal: this.session.agent.signal,
-			abort: () => this.session.abort(),
+			abort: () => {
+				this.restoreQueuedMessagesToEditor({ abort: true });
+			},
 			hasPendingMessages: () => this.session.pendingMessageCount > 0,
 			shutdown: () => {
 				this.shutdownRequested = true;