feat: return worktree info in orchestrator.start response

- Add WorktreePath and WorktreeBranch to StartTaskResponse
- Add those fields to TaskExecution and LaunchAgentResponse
- Store worktree_path and worktree_branch in AgentInstance metadata
- Update frontend to use worktree info from start response directly

apps/backend/cmd/kandev/main.go

@@ -599,10 +599,23 @@ func (a *lifecycleAdapter) LaunchAgent(ctx context.Context, req *executor.Launch
 
 	// Streaming is now handled by the lifecycle manager
 
+	// Extract worktree info from metadata if available
+	var worktreePath, worktreeBranch string
+	if instance.Metadata != nil {
+		if path, ok := instance.Metadata["worktree_path"].(string); ok {
+			worktreePath = path
+		}
+		if branch, ok := instance.Metadata["worktree_branch"].(string); ok {
+			worktreeBranch = branch
+		}
+	}
+
 	return &executor.LaunchAgentResponse{
 		AgentInstanceID: instance.ID,
 		ContainerID:     instance.ContainerID,
 		Status:          instance.Status,
+		WorktreePath:    worktreePath,
+		WorktreeBranch:  worktreeBranch,
 	}, nil
 }
 

apps/backend/internal/agent/lifecycle/manager.go

@@ -304,6 +304,7 @@ func (m *Manager) Launch(ctx context.Context, req *LaunchRequest) (*AgentInstanc
 	workspacePath := req.WorkspacePath
 	var mainRepoGitDir string // Path to main repo's .git directory for container mount
 	var worktreeID string     // Store worktree ID for session resumption
+	var worktreeBranch string // Store worktree branch for API responses
 	if req.UseWorktree && m.worktreeMgr != nil && req.RepositoryPath != "" {
 		wt, err := m.getOrCreateWorktree(ctx, req)
 		if err != nil {
@@ -314,6 +315,7 @@ func (m *Manager) Launch(ctx context.Context, req *LaunchRequest) (*AgentInstanc
 		} else {
 			workspacePath = wt.Path
 			worktreeID = wt.ID
+			worktreeBranch = wt.Branch
 			// Git worktrees reference the main repo's .git directory via a .git file
 			// The worktree metadata in .git/worktrees/{name} contains a 'commondir' file
 			// that points back to the main .git directory (usually '../..')
@@ -365,9 +367,11 @@ func (m *Manager) Launch(ctx context.Context, req *LaunchRequest) (*AgentInstanc
 	if instanceMetadata == nil {
 		instanceMetadata = make(map[string]interface{})
 	}
-	// Store worktree_id in metadata for session resumption
+	// Store worktree info in metadata for session resumption and API responses
 	if worktreeID != "" {
 		instanceMetadata["worktree_id"] = worktreeID
+		instanceMetadata["worktree_path"] = workspacePath
+		instanceMetadata["worktree_branch"] = worktreeBranch
 	}
 	instance := &AgentInstance{
 		ID:          instanceID,

apps/backend/internal/orchestrator/controller/controller.go

@@ -67,12 +67,22 @@ func (c *Controller) StartTask(ctx context.Context, req dto.StartTaskRequest) (d
 		return dto.StartTaskResponse{}, err
 	}
 
-	return dto.StartTaskResponse{
+	resp := dto.StartTaskResponse{
 		Success:         true,
 		TaskID:          execution.TaskID,
 		AgentInstanceID: execution.AgentInstanceID,
 		Status:          string(execution.Status),
-	}, nil
+	}
+
+	// Include worktree info if available
+	if execution.WorktreePath != "" {
+		resp.WorktreePath = &execution.WorktreePath
+	}
+	if execution.WorktreeBranch != "" {
+		resp.WorktreeBranch = &execution.WorktreeBranch
+	}
+
+	return resp, nil
 }
 
 // StopTask stops task execution

apps/backend/internal/orchestrator/dto/dto.go

@@ -51,10 +51,12 @@ type StartTaskRequest struct {
 
 // StartTaskResponse is the response for orchestrator.start
 type StartTaskResponse struct {
-	Success         bool   `json:"success"`
-	TaskID          string `json:"task_id"`
-	AgentInstanceID string `json:"agent_instance_id"`
-	Status          string `json:"status"`
+	Success         bool    `json:"success"`
+	TaskID          string  `json:"task_id"`
+	AgentInstanceID string  `json:"agent_instance_id"`
+	Status          string  `json:"status"`
+	WorktreePath    *string `json:"worktree_path,omitempty"`
+	WorktreeBranch  *string `json:"worktree_branch,omitempty"`
 }
 
 // StopTaskRequest is the payload for orchestrator.stop

apps/backend/internal/orchestrator/executor/executor.go

@@ -77,6 +77,8 @@ type LaunchAgentResponse struct {
 	AgentInstanceID string
 	ContainerID     string
 	Status          v1.AgentStatus
+	WorktreePath    string
+	WorktreeBranch  string
 }
 
 // TaskExecution tracks an active task execution (kept for API compatibility)
@@ -90,6 +92,9 @@ type TaskExecution struct {
 	LastUpdate      time.Time
 	// SessionID is the database ID of the agent session
 	SessionID string
+	// Worktree info for the agent
+	WorktreePath   string
+	WorktreeBranch string
 }
 
 // FromAgentSession converts a models.AgentSession to TaskExecution
@@ -341,6 +346,8 @@ func (e *Executor) Execute(ctx context.Context, task *v1.Task) (*TaskExecution,
 		Progress:        0,
 		LastUpdate:      now,
 		SessionID:       sessionID,
+		WorktreePath:    resp.WorktreePath,
+		WorktreeBranch:  resp.WorktreeBranch,
 	}
 
 	e.mu.Lock()
@@ -351,7 +358,9 @@ func (e *Executor) Execute(ctx context.Context, task *v1.Task) (*TaskExecution,
 		zap.String("task_id", task.ID),
 		zap.String("session_id", sessionID),
 		zap.String("agent_instance_id", resp.AgentInstanceID),
-		zap.String("container_id", resp.ContainerID))
+		zap.String("container_id", resp.ContainerID),
+		zap.String("worktree_path", resp.WorktreePath),
+		zap.String("worktree_branch", resp.WorktreeBranch))
 
 	return execution, nil
 }

apps/web/app/task/[id]/page-client.tsx

@@ -162,25 +162,25 @@ export default function TaskPage({ task: initialTask }: TaskPageClientProps) {
     try {
       // Use task's agent_type if set, otherwise default to 'augment-agent'
       const agentType = task.agent_type ?? 'augment-agent';
-      await client.request('orchestrator.start', {
+      interface StartResponse {
+        success: boolean;
+        task_id: string;
+        agent_instance_id: string;
+        status: string;
+        worktree_path?: string;
+        worktree_branch?: string;
+      }
+      const response = await client.request<StartResponse>('orchestrator.start', {
         task_id: task.id,
         agent_type: agentType,
       }, 15000);
       setIsAgentRunning(true);
 
-      // Fetch updated task info after agent starts (to get worktree path/branch)
-      // Wait a bit for the worktree to be created
-      setTimeout(async () => {
-        try {
-          const updatedTask = await client.request<Task>('task.get', { id: task.id }, 5000);
-          if (updatedTask?.worktree_path) {
-            setWorktreePath(updatedTask.worktree_path);
-            setWorktreeBranch(updatedTask.worktree_branch ?? null);
-          }
-        } catch (err) {
-          console.error('Failed to fetch updated task info:', err);
-        }
-      }, 1000);
+      // Update worktree info from response
+      if (response?.worktree_path) {
+        setWorktreePath(response.worktree_path);
+        setWorktreeBranch(response.worktree_branch ?? null);
+      }
     } catch (error) {
       console.error('Failed to start agent:', error);
     } finally {