fix: skip git polling when workspace has no valid git repository (#541)

apps/backend/internal/agentctl/server/process/workspace_git_poll.go

@@ -17,6 +17,14 @@ import (
 func (wt *WorkspaceTracker) pollGitChanges(ctx context.Context) {
 	defer wt.wg.Done()
 
+	// If no valid git index was found at startup, git commands will fail.
+	// Exit immediately to avoid repeated rev-parse probes on a non-repo directory.
+	if wt.gitIndexPath == "" {
+		wt.logger.Warn("no valid git repository found, git polling not started",
+			zap.String("workDir", wt.workDir))
+		return
+	}
+
 	ticker := time.NewTicker(wt.gitPollInterval)
 	defer ticker.Stop()
 

apps/backend/internal/agentctl/server/process/workspace_monitor.go

@@ -35,6 +35,15 @@ const maxConsecutiveGitFailures = 5
 func (wt *WorkspaceTracker) monitorLoop(ctx context.Context) {
 	defer wt.wg.Done()
 
+	// If no valid git index was found at startup, there's nothing to poll.
+	// Exit immediately to avoid spamming "git diff-files: exit status 128" warnings
+	// every poll cycle until the consecutive failure threshold is reached.
+	if wt.gitIndexPath == "" {
+		wt.logger.Warn("no valid git repository found, file monitor not polling",
+			zap.String("workDir", wt.workDir))
+		return
+	}
+
 	ticker := time.NewTicker(wt.filePollInterval)
 	defer ticker.Stop()
 

apps/backend/internal/agentctl/server/process/workspace_monitor_test.go

@@ -43,6 +43,45 @@ func TestWorkspaceTracker_StopsWhenWorkDirDeleted(t *testing.T) {
 	}
 }
 
+func TestWorkspaceTracker_MonitorExitsWhenNoGitRepo(t *testing.T) {
+	isolateTestGitEnv(t)
+
+	// Create a plain directory with no git repo — resolveGitIndexPath returns ""
+	plainDir, err := os.MkdirTemp("", "test-no-git-*")
+	if err != nil {
+		t.Fatalf("failed to create temp dir: %v", err)
+	}
+	t.Cleanup(func() { _ = os.RemoveAll(plainDir) })
+
+	log := newTestLogger(t)
+	wt := NewWorkspaceTracker(plainDir, log)
+	// Use 500ms intervals so the 5-failure threshold takes ~2.5s.
+	// The fix should make monitorLoop exit immediately (well under 500ms).
+	wt.filePollInterval = 500 * time.Millisecond
+	wt.gitPollInterval = 500 * time.Millisecond
+
+	if wt.gitIndexPath != "" {
+		t.Fatalf("expected empty gitIndexPath for non-git directory, got %q", wt.gitIndexPath)
+	}
+
+	wt.Start(context.Background())
+
+	// monitorLoop should exit immediately without attempting git commands.
+	// Without the fix, it takes ~2.5s (5 failures × 500ms poll interval).
+	done := make(chan struct{})
+	go func() {
+		wt.wg.Wait()
+		close(done)
+	}()
+
+	select {
+	case <-done:
+		// Both goroutines exited quickly — success
+	case <-time.After(1 * time.Second):
+		t.Fatal("workspace tracker did not stop promptly when started without a valid git repo")
+	}
+}
+
 func TestWorkspaceTracker_StopsWhenGitBroken(t *testing.T) {
 	isolateTestGitEnv(t)