Start preview session without waiting for repo selection

Author: charlesvien

apps/twig/src/main/services/agent/service.ts

@@ -416,7 +416,7 @@ export class AgentService extends TypedEventEmitter<AgentServiceEvents> {
     const {
       taskId,
       taskRunId,
-      repoPath,
+      repoPath: rawRepoPath,
       credentials,
       logUrl,
       sessionId: existingSessionId,
@@ -425,6 +425,9 @@ export class AgentService extends TypedEventEmitter<AgentServiceEvents> {
       permissionMode,
     } = config;
 
+    // Preview sessions don't need a real repo — use a temp directory
+    const repoPath = taskId === "__preview__" ? tmpdir() : rawRepoPath;
+
     if (!isRetry) {
       const existing = this.sessions.get(taskRunId);
       if (existing) {

apps/twig/src/renderer/features/sessions/service/service.ts

@@ -480,7 +480,6 @@ export class SessionService {
 
   async startPreviewSession(params: {
     adapter: "claude" | "codex";
-    repoPath?: string;
   }): Promise<void> {
     this.previewAbort?.abort();
     const abort = new AbortController();
@@ -508,7 +507,7 @@ export class SessionService {
       const result = await trpcVanilla.agent.start.mutate({
         taskId: PREVIEW_TASK_ID,
         taskRunId,
-        repoPath: params.repoPath || "~",
+        repoPath: "__preview__",
         apiKey: auth.apiKey,
         apiHost: auth.apiHost,
         projectId: auth.projectId,

apps/twig/src/renderer/features/task-detail/components/TaskInput.tsx

@@ -60,7 +60,7 @@ export function TaskInput() {
     thoughtOption,
     previewTaskId,
     isConnecting,
-  } = usePreviewSession(adapter, selectedDirectory || undefined);
+  } = usePreviewSession(adapter);
 
   useEffect(() => {
     if (view.folderId) {

apps/twig/src/renderer/features/task-detail/hooks/usePreviewSession.ts

@@ -24,21 +24,20 @@ interface PreviewSessionResult {
  * Manages a lightweight preview session that provides adapter-specific
  * config options (models, modes, reasoning levels) for the task input page.
  *
- * Starts a new preview session when adapter or repoPath change,
+ * Starts a new preview session when adapter changes,
  * and cleans up on unmount or when inputs change.
  */
 export function usePreviewSession(
   adapter: "claude" | "codex",
-  repoPath: string | undefined,
 ): PreviewSessionResult {
   useEffect(() => {
     const service = getSessionService();
-    service.startPreviewSession({ adapter, repoPath });
+    service.startPreviewSession({ adapter });
 
     return () => {
       service.cancelPreviewSession();
     };
-  }, [adapter, repoPath]);
+  }, [adapter]);
 
   const session = useSessionForTask(PREVIEW_TASK_ID);
   const modeOption = useModeConfigOptionForTask(PREVIEW_TASK_ID);