feat: abort controller for work order processing

Add end-to-end abort support: AbortSignal in @gadget/ai providers,
abortWorkOrder socket message, drone AbortController handling,
Cancel button and double-Esc in frontend, and aborted turn status display.

.gitignore

@@ -1,4 +1,5 @@
-gadget*log
+gadget-code.*.log
+gadget-drone.*.log
 logfetch
 
 .gadget

gadget-code/frontend/src/components/ChatTurn.tsx

@@ -49,7 +49,9 @@ const ChatTurn = memo(function ChatTurn({ turn }: ChatTurnProps) {
               ? "text-green-500"
               : turn.status === "error"
                 ? "text-red-500"
-                : "text-yellow-500"
+                : turn.status === "aborted"
+                  ? "text-yellow-500"
+                  : "text-yellow-500"
           }
         >
           {statusLabel}
@@ -88,6 +90,17 @@ const ChatTurn = memo(function ChatTurn({ turn }: ChatTurnProps) {
         </div>
       )}
 
+      {/* Aborted notice */}
+      {turn.status === "aborted" && (
+        <div className="max-w-[80%] ml-0 mb-2">
+          <div className="bg-bg-tertiary border border-border-default rounded p-3">
+            <div className="whitespace-pre-wrap text-sm text-text-secondary">
+              The turn was aborted by you.
+            </div>
+          </div>
+        </div>
+      )}
+
       {/* User Prompt */}
       <div className="max-w-[80%] ml-0 mb-4">
         <div className="bg-[#4a0000] text-white rounded p-4">

gadget-code/frontend/src/lib/api.ts

@@ -408,7 +408,7 @@ export interface ChatTurn {
   provider: string | AiProvider;
   llm: string;
   mode: ChatSessionMode;
-  status: "processing" | "finished" | "error";
+  status: "processing" | "finished" | "aborted" | "error";
   prompts: ChatTurnPrompts;
   blocks: ChatTurnBlock[];
   errorMessage?: string;

gadget-code/frontend/src/lib/socket.ts

@@ -42,6 +42,7 @@ export interface ServerToClientEvents {
 
 export interface ClientToServerEvents {
   submitPrompt: (content: string) => void;
+  abortWorkOrder: (cb: (success: boolean, message?: string) => void) => void;
   requestSessionLock: (
     registration: any,
     project: any,
@@ -353,6 +354,16 @@ class SocketClient {
     }
   }
 
+  abortWorkOrder(cb?: (success: boolean, message?: string) => void): void {
+    if (this._socket?.connected) {
+      this._socket.emit('abortWorkOrder', (success: boolean, message?: string) => {
+        cb?.(success, message);
+      });
+    } else {
+      cb?.(false, 'Socket not connected');
+    }
+  }
+
   requestSessionLock(
     registration: any,
     project: any,

gadget-code/frontend/src/pages/ChatSessionView.tsx

@@ -50,6 +50,7 @@ export default function ChatSessionView() {
   const [turns, setTurns] = useState<ChatTurn[]>([]);
   const [promptInput, setPromptInput] = useState('');
   const [isProcessing, setIsProcessing] = useState(false);
+  const [isAborting, setIsAborting] = useState(false);
   const [loading, setLoading] = useState(true);
   const [error, setError] = useState('');
   const [sessionLocked, setSessionLocked] = useState(true);
@@ -81,6 +82,8 @@ export default function ChatSessionView() {
   const updateRafRef = useRef<number | null>(null);
   const currentTurnIdRef = useRef<string | null>(null);
   const streamingStateRef = useRef<Map<string, StreamingState>>(new Map());
+  const escTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null);
+  const escFlagRef = useRef(false);
   const subagentStateRef = useRef<Map<string, SubagentStreamState>>(new Map());
   const sessionRef = useRef<ChatSession | null>(null);
   const projectRef = useRef<Project | null>(null);
@@ -534,6 +537,16 @@ export default function ChatSessionView() {
     scheduleUpdate();
   }, [mergePendingUpdate, scheduleUpdate]);
 
+  const showToast = useCallback((message: string) => {
+    setToast(message);
+    if (toastTimerRef.current) {
+      clearTimeout(toastTimerRef.current);
+    }
+    toastTimerRef.current = setTimeout(() => {
+      setToast(null);
+    }, 4000);
+  }, []);
+
   const handleWorkOrderComplete = useCallback((turnId: string, success: boolean, message?: string) => {
     // Backend has already flushed and persisted all streaming content
     // Just clean up frontend streaming state and update status
@@ -551,19 +564,38 @@ export default function ChatSessionView() {
       subagentStateRef.current.delete(agentId);
     }
 
-    setTurns(prevTurns =>
-      prevTurns.map(turn =>
-        turn._id === turnId
-          ? { ...turn, status: success ? 'finished' : 'error', errorMessage: message && !success ? message : turn.errorMessage }
-          : turn
-      )
-    );
+    if (success && message === 'aborted') {
+      setTurns(prevTurns =>
+        prevTurns.map(turn =>
+          turn._id === turnId
+            ? { ...turn, status: 'aborted', errorMessage: 'The turn was aborted by you.' }
+            : turn
+        )
+      );
+      showToast('The turn was aborted by you.');
+    } else {
+      setTurns(prevTurns =>
+        prevTurns.map(turn =>
+          turn._id === turnId
+            ? { ...turn, status: success ? 'finished' : 'error', errorMessage: message && !success ? message : turn.errorMessage }
+            : turn
+        )
+      );
+      if (!success) {
+        setError(message || 'Work order failed');
+      }
+    }
+
+    // Clean up abort state
+    if (escTimerRef.current) {
+      clearTimeout(escTimerRef.current);
+      escTimerRef.current = null;
+    }
+    escFlagRef.current = false;
+    setIsAborting(false);
     setIsProcessing(false);
     currentTurnIdRef.current = null;
-    if (!success) {
-      setError(message || 'Work order failed');
-    }
-  }, []);
+  }, [showToast]);
 
   const handleWorkspaceModeChanged = useCallback((mode: string) => {
     setWorkspaceMode(mode as WorkspaceMode);
@@ -712,16 +744,6 @@ export default function ChatSessionView() {
     });
   }, [updateSubagentBlock]);
 
-  const showToast = useCallback((message: string) => {
-    setToast(message);
-    if (toastTimerRef.current) {
-      clearTimeout(toastTimerRef.current);
-    }
-    toastTimerRef.current = setTimeout(() => {
-      setToast(null);
-    }, 4000);
-  }, []);
-
   const handleWorkspaceModeChange = async (mode: WorkspaceMode) => {
     if (!session || !project) return;
 
@@ -936,6 +958,64 @@ export default function ChatSessionView() {
     });
   };
 
+  const handleCancel = useCallback(() => {
+    if (isAborting) return;
+    setIsAborting(true);
+    socketClient.abortWorkOrder((success, message) => {
+      if (success) {
+        showToast('Aborting Agentic Workflow Loop...');
+      } else {
+        showToast(message || 'Failed to abort');
+        setIsAborting(false);
+      }
+    });
+  }, [isAborting, showToast]);
+
+  // Global Esc key handler for abort: first Esc shows prompt, second Esc within 3s aborts
+  useEffect(() => {
+    if (!isProcessing) {
+      if (escTimerRef.current) {
+        clearTimeout(escTimerRef.current);
+        escTimerRef.current = null;
+      }
+      escFlagRef.current = false;
+      return;
+    }
+
+    const handleKeyDown = (e: KeyboardEvent) => {
+      if (e.key !== 'Escape') return;
+      e.preventDefault();
+
+      if (!escFlagRef.current) {
+        escFlagRef.current = true;
+        showToast('Press Esc again to abort');
+        escTimerRef.current = setTimeout(() => {
+          escFlagRef.current = false;
+          setToast(null);
+          escTimerRef.current = null;
+        }, 3000);
+      } else {
+        if (escTimerRef.current) {
+          clearTimeout(escTimerRef.current);
+          escTimerRef.current = null;
+        }
+        escFlagRef.current = false;
+        setToast(null);
+        handleCancel();
+      }
+    };
+
+    window.addEventListener('keydown', handleKeyDown);
+    return () => {
+      window.removeEventListener('keydown', handleKeyDown);
+      if (escTimerRef.current) {
+        clearTimeout(escTimerRef.current);
+        escTimerRef.current = null;
+      }
+      escFlagRef.current = false;
+    };
+  }, [isProcessing, showToast, handleCancel]);
+
   const scrollToBottom = () => {
     messagesEndRef.current?.scrollIntoView({ behavior: 'smooth' });
   };
@@ -1037,13 +1117,24 @@ export default function ChatSessionView() {
                 rows={3}
                 disabled={promptDisabled}
               />
-              <button
-                type="submit"
-                disabled={promptDisabled || !promptInput.trim()}
-                className="px-6 py-2 bg-brand text-white rounded hover:bg-red-700 transition-colors disabled:opacity-50 disabled:cursor-not-allowed"
-              >
-                {isProcessing ? 'Processing...' : 'Send'}
-              </button>
+              {isProcessing ? (
+                <button
+                  type="button"
+                  onClick={handleCancel}
+                  disabled={isAborting}
+                  className="px-6 py-2 bg-red-600 text-white rounded hover:bg-red-700 transition-colors disabled:opacity-50 disabled:cursor-not-allowed"
+                >
+                  {isAborting ? 'Aborting...' : 'Cancel'}
+                </button>
+              ) : (
+                <button
+                  type="submit"
+                  disabled={promptDisabled || !promptInput.trim()}
+                  className="px-6 py-2 bg-brand text-white rounded hover:bg-brand/80 transition-colors disabled:opacity-50 disabled:cursor-not-allowed"
+                >
+                  Send
+                </button>
+              )}
             </form>
           </div>
         </div>

gadget-code/src/lib/code-session.ts

@@ -19,6 +19,7 @@ import {
   ChatTurnDocument,
   WorkspaceMode,
   SubmitPromptCallback,
+  AbortWorkOrderCallback,
 } from "@gadget/api";
 
 import ChatSession from "../models/chat-session.ts";
@@ -55,6 +56,7 @@ export class CodeSession extends SocketSession {
       this.onRequestWorkspaceMode.bind(this),
     );
     this.socket.on("submitPrompt", this.onSubmitPrompt.bind(this));
+    this.socket.on("abortWorkOrder", this.onAbortWorkOrder.bind(this));
     this.socket.on("releaseSessionLock", this.onReleaseSessionLock.bind(this));
     this.socket.on("sessionHeartbeat", this.onSessionHeartbeat.bind(this));
     
@@ -401,6 +403,23 @@ export class CodeSession extends SocketSession {
     }
   }
 
+  /**
+   * Called when the IDE sends an abortWorkOrder event to cancel the
+   * currently running work order. Forwards to the drone.
+   */
+  onAbortWorkOrder(cb: AbortWorkOrderCallback): void {
+    if (!this.selectedDrone) {
+      return cb(false, "No drone selected");
+    }
+    try {
+      const droneSession = SocketService.getDroneSession(this.selectedDrone);
+      droneSession.socket.emit("abortWorkOrder", cb);
+    } catch (error) {
+      this.log.error("failed to forward abortWorkOrder to drone", { error });
+      cb(false, "Failed to reach drone");
+    }
+  }
+
   /**
    * Called when the IDE sends a releaseSessionLock event to release a
    * previously-acquired session lock on a gadget-drone instance.

gadget-code/src/lib/drone-session.ts

@@ -288,9 +288,14 @@ export class DroneSession extends SocketSession {
 
       const turn = await ChatTurn.findById(turnId);
       if (turn) {
-        turn.status = success ? ChatTurnStatus.Finished : ChatTurnStatus.Error;
-        if (!success && message) {
-          turn.errorMessage = message;
+        if (success && message === "aborted") {
+          turn.status = ChatTurnStatus.Aborted;
+          turn.errorMessage = "The turn was aborted by you.";
+        } else {
+          turn.status = success ? ChatTurnStatus.Finished : ChatTurnStatus.Error;
+          if (!success && message) {
+            turn.errorMessage = message;
+          }
         }
         await turn.save();
       }

gadget-drone/src/gadget-drone.ts

@@ -248,6 +248,10 @@ class GadgetDrone extends GadgetProcess {
         this.onReleaseSessionLock.bind(this),
       );
       this.socket.on("sessionHeartbeat", this.onSessionHeartbeat.bind(this));
+      this.socket.on(
+        "abortWorkOrder",
+        this.onAbortWorkOrder.bind(this),
+      );
       this.socket.on(
         "requestTermination",
         this.onRequestTermination.bind(this),
@@ -704,6 +708,16 @@ class GadgetDrone extends GadgetProcess {
     });
   }
 
+  async onAbortWorkOrder(cb: (success: boolean, message?: string) => void): Promise<void> {
+    this.log.info("abortWorkOrder received from platform", {
+      registrationId: this.registration?._id,
+      isProcessing: this.isProcessingWorkOrder,
+    });
+
+    const aborted = AgentService.abortCurrentWorkOrder();
+    cb(aborted, aborted ? "Abort signaled" : "No active work order to abort");
+  }
+
   async onRequestTermination(cb: (success: boolean) => void): Promise<void> {
     this.log.info("requestTermination received from platform", {
       registrationId: this.registration?._id,

gadget-drone/src/services/agent.ts

@@ -79,6 +79,7 @@ class AgentService extends GadgetService {
   private currentWorkOrder: IAgentWorkOrder | null = null;
   private currentSocket: DroneSocket | null = null;
   private currentToolCallId: string | null = null;
+  private abortController: AbortController | null = null;
 
   get name(): string {
     return "AgentService";
@@ -143,6 +144,7 @@ class AgentService extends GadgetService {
   ): Promise<void> {
     this.currentWorkOrder = workOrder;
     this.currentSocket = socket;
+    this.abortController = new AbortController();
 
     const { turn } = workOrder;
     let toolCallCount = 0;
@@ -204,6 +206,7 @@ class AgentService extends GadgetService {
         const chatOptions: IAiChatOptions = {
           context: messages,
           tools: this.getToolsForMode(turn.mode),
+          signal: this.abortController.signal,
         };
 
         let response: IAiChatResponse;
@@ -302,6 +305,11 @@ class AgentService extends GadgetService {
 
       socket.emit("workOrderComplete", turn._id, true);
     } catch (cause) {
+      if (cause instanceof Error && cause.name === "AbortError") {
+        this.log.info("work order aborted by user", { turnId: turn._id });
+        socket.emit("workOrderComplete", turn._id, true, "aborted");
+        return;
+      }
       const msg = cause instanceof Error ? cause.message : String(cause);
       this.log.error("agent loop failed, sending workOrderComplete(false)", {
         turnId: turn._id,
@@ -309,9 +317,21 @@ class AgentService extends GadgetService {
       });
       socket.emit("workOrderComplete", turn._id, false, msg);
       throw cause;
+    } finally {
+      this.abortController = null;
     }
   }
 
+  /**
+   * Signals the abort controller for the currently running work order.
+   * Returns true if an abort was signaled, false if there was no active work order.
+   */
+  abortCurrentWorkOrder(): boolean {
+    if (!this.abortController) return false;
+    this.abortController.abort();
+    return true;
+  }
+
   buildSessionContext(workOrder: IAgentWorkOrder): IContextChatMessage[] {
     const session = workOrder.turn.session as IChatSession;
     if (!session.user) {
@@ -596,6 +616,7 @@ class AgentService extends GadgetService {
         const chatOptions: IAiChatOptions = {
           context: messages,
           tools,
+          signal: this.abortController?.signal,
         };
 
         this.log.info("subagent loop iteration", {

packages/ai/src/api.ts

@@ -46,6 +46,7 @@ export interface IAiInferenceStats {
 export interface IAiGenerateOptions {
   prompt: string;
   systemPrompt?: string;
+  signal?: AbortSignal;
 }
 
 export interface IAiGenerateResponse {
@@ -89,6 +90,7 @@ export interface IAiChatOptions {
   userPrompt?: string;
   context?: IContextChatMessage[];
   tools?: IAiTool[];
+  signal?: AbortSignal;
 }
 
 export interface IAiChatResponse {

packages/ai/src/ollama.ts

@@ -144,11 +144,16 @@ export class OllamaAiApi extends AiApi {
       modelId: model.modelId,
     });
 
+    if (options.signal?.aborted) {
+      throw new DOMException("The operation was aborted", "AbortError");
+    }
+
     const response = await this.client.generate({
       model: model.modelId,
       prompt: options.prompt,
       system: options.systemPrompt,
       stream: true,
+      ...(options.signal ? { signal: options.signal } : {}),
       options: {
         num_ctx: model.params.numCtx,
         num_predict: model.params.numPredict,
@@ -161,6 +166,10 @@ export class OllamaAiApi extends AiApi {
     };
     let lastChunk;
     for await (const chunk of response) {
+      if (options.signal?.aborted) {
+        throw new DOMException("The operation was aborted", "AbortError");
+      }
+
       lastChunk = chunk;
 
       if (chunk.thinking) {
@@ -216,6 +225,10 @@ export class OllamaAiApi extends AiApi {
       modelId: model.modelId,
     });
 
+    if (options.signal?.aborted) {
+      throw new DOMException("The operation was aborted", "AbortError");
+    }
+
     const messages: OllamaMessage[] = [];
 
     if (options.systemPrompt) {
@@ -268,6 +281,7 @@ export class OllamaAiApi extends AiApi {
       stream: true,
       think: model.params.reasoning,
       tools: ollamaTools,
+      ...(options.signal ? { signal: options.signal } : {}),
       options: {
         num_ctx: model.params.numCtx,
         num_predict: model.params.numPredict,
@@ -280,6 +294,10 @@ export class OllamaAiApi extends AiApi {
     const toolCalls: IToolCall[] = [];
 
     for await (const chunk of response) {
+      if (options.signal?.aborted) {
+        throw new DOMException("The operation was aborted", "AbortError");
+      }
+
       lastChunk = chunk;
 
       if (chunk.message.thinking) {

packages/ai/src/openai.ts

@@ -192,6 +192,10 @@ export class OpenAiApi extends AiApi {
       modelId: model.modelId,
     });
 
+    if (options.signal?.aborted) {
+      throw new DOMException("The operation was aborted", "AbortError");
+    }
+
     const startTime = Date.now();
     const response = await this.client.chat.completions.create({
       model: model.modelId,
@@ -202,6 +206,7 @@ export class OpenAiApi extends AiApi {
         { role: "user" as const, content: options.prompt },
       ],
       stream: true,
+      ...(options.signal ? { signal: options.signal } : {}),
       ...(model.params.maxCompletionTokens
         ? { max_completion_tokens: model.params.maxCompletionTokens }
         : {}),
@@ -219,6 +224,10 @@ export class OpenAiApi extends AiApi {
     let accumulatedThinking = "";
 
     for await (const chunk of response) {
+      if (options.signal?.aborted) {
+        throw new DOMException("The operation was aborted", "AbortError");
+      }
+
       const delta = chunk.choices[0]?.delta;
       if (delta) {
         if (delta.content) {
@@ -282,6 +291,7 @@ export class OpenAiApi extends AiApi {
       messages,
       tools,
       streamCallback,
+      options.signal,
     );
 
     await this.log.debug("OpenAI chat stream iteration finished", {
@@ -295,7 +305,7 @@ export class OpenAiApi extends AiApi {
     });
 
     if (this.isEmptyIteration(iteration)) {
-      iteration = await this.readNonStreamingChatCompletion(model, messages, tools);
+      iteration = await this.readNonStreamingChatCompletion(model, messages, tools, options.signal);
       if (streamCallback && iteration.response) {
         await streamCallback({ type: "response", data: iteration.response });
       }
@@ -370,12 +380,18 @@ export class OpenAiApi extends AiApi {
     messages: ChatCompletionMessageParam[],
     tools: ChatCompletionTool[],
     streamCallback?: IAiResponseStreamFn,
+    signal?: AbortSignal,
   ): Promise<OpenAiChatIterationResult> {
+    if (signal?.aborted) {
+      throw new DOMException("The operation was aborted", "AbortError");
+    }
+
     const response = await this.client.chat.completions.create({
       model: model.modelId,
       messages,
       tools,
       stream: true,
+      ...(signal ? { signal } : {}),
       ...(model.params.maxCompletionTokens
         ? { max_completion_tokens: model.params.maxCompletionTokens }
         : {}),
@@ -398,6 +414,10 @@ export class OpenAiApi extends AiApi {
     const toolCallMap = new Map<number, StreamingToolCallAccumulator>();
 
     for await (const chunk of response) {
+      if (signal?.aborted) {
+        throw new DOMException("The operation was aborted", "AbortError");
+      }
+
       chunkCount++;
       finishReason = chunk.choices[0]?.finish_reason ?? finishReason;
       const delta = chunk.choices[0]?.delta;
@@ -439,12 +459,14 @@ export class OpenAiApi extends AiApi {
     model: IAiModelConfig,
     messages: ChatCompletionMessageParam[],
     tools: ChatCompletionTool[],
+    signal?: AbortSignal,
   ): Promise<OpenAiChatIterationResult> {
     const response = await this.client.chat.completions.create({
       model: model.modelId,
       messages,
       tools,
       stream: false,
+      ...(signal ? { signal } : {}),
       ...(model.params.maxCompletionTokens
         ? { max_completion_tokens: model.params.maxCompletionTokens }
         : {}),

packages/api/src/messages/ide.ts

@@ -80,6 +80,17 @@ export type ReleaseSessionLockMessage = (
   cb: ReleaseSessionLockCallback,
 ) => void;
 
+/*
+ * abortWorkOrder
+ */
+
+export type AbortWorkOrderCallback = (
+  success: boolean,
+  message?: string,
+) => void;
+
+export type AbortWorkOrderMessage = (cb: AbortWorkOrderCallback) => void;
+
 /*
  * sessionHeartbeat
  */

packages/api/src/messages/socket.ts

@@ -17,6 +17,7 @@ import {
 } from "./drone.ts";
 import { SessionUpdatedMessage } from "./web.ts";
 import {
+  AbortWorkOrderMessage,
   ReleaseSessionLockMessage,
   RequestSessionLockMessage,
   RequestWorkspaceModeMessage,
@@ -50,6 +51,7 @@ export interface ClientToServerEvents {
   requestSessionLock: RequestSessionLockMessage;
   requestWorkspaceMode: RequestWorkspaceModeMessage;
   submitPrompt: SubmitPromptMessage;
+  abortWorkOrder: AbortWorkOrderMessage;
   releaseSessionLock: ReleaseSessionLockMessage;
   sessionHeartbeat: SessionHeartbeatMessage;
 
@@ -111,6 +113,7 @@ export interface ServerToClientEvents {
   requestWorkspaceMode: RequestWorkspaceModeMessage;
   releaseSessionLock: ReleaseSessionLockMessage;
   sessionHeartbeat: SessionHeartbeatMessage;
+  abortWorkOrder: AbortWorkOrderMessage;
   processWorkOrder: ProcessWorkOrderMessage;
   crashRecoveryResponse: CrashRecoveryResponseMessage;
   requestTermination: RequestTerminationMessage;