feat(cli): add --title flag for a custom browser tab title

README.md

@@ -156,6 +156,7 @@ Stdin mode is selected with intent-first rules:
 | `--keep-alive`        | false           | Keep server running after browser disconnects (stop manually with Ctrl+C)                               |
 | `--background`        | false           | Keep the server running in the background and output JSON connection info                               |
 | `--context <lines>`   | git default (3) | Limit surrounding context lines per change (`0` shows changes only; not available with `--pr` or stdin) |
+| `--title <title>`     | -               | Custom browser tab title, to tell review sessions apart when several difit instances are open           |
 
 ## 💬 Comment System
 

src/cli/index.ts

@@ -90,6 +90,7 @@ interface CliOptions {
   background?: boolean;
   context?: number;
   mergeBase?: boolean;
+  title?: string;
 }
 
 const program = new Command();
@@ -128,6 +129,7 @@ program
     '--merge-base',
     'resolve the base revision with git merge-base before diffing (Git revision mode only)',
   )
+  .option('--title <title>', 'custom browser tab title for this review session')
   .action(async (commitish: string, compareWith: string | undefined, options: CliOptions) => {
     try {
       const isBackgroundChild = process.env[BACKGROUND_CHILD_ENV] === '1';
@@ -234,6 +236,7 @@ program
           openBrowser: options.open,
           clearComments: options.clean,
           keepAlive: options.keepAlive,
+          title: options.title,
           ...(commentImports.length > 0 ? { commentImports } : {}),
         });
 
@@ -297,6 +300,7 @@ program
         contextLines: options.context,
         diffMode: determineDiffMode(selection, compareWith),
         repoPath,
+        title: options.title,
         ...(commentImports.length > 0 ? { commentImports } : {}),
       });
 

src/client/App.test.tsx

@@ -1078,3 +1078,21 @@ describe('App Component - Mobile sidebar auto-close', () => {
     });
   });
 });
+
+describe('App Component - Custom tab title', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+    mockComments = [];
+    mockConfirm.mockReturnValue(false);
+  });
+
+  it('sets document.title from the diff response when --title is provided', async () => {
+    mockFetch({ ...mockDiffResponse, title: 'DEV-1234 review' });
+
+    renderApp();
+
+    await waitFor(() => {
+      expect(document.title).toBe('DEV-1234 review');
+    });
+  });
+});

src/client/App.tsx

@@ -717,6 +717,7 @@ function App() {
         }
         setDiffData(data);
         setDiffDataVersion((prev) => prev + 1);
+        if (data.title) document.title = data.title;
 
         // Update resolved revision state from server response
         setResolvedBaseRevision(

src/server/server.test.ts

@@ -466,6 +466,21 @@ describe('Server Integration Tests', () => {
       expect(data).toHaveProperty('requestedTargetCommitish', 'HEAD');
     });
 
+    it('GET /api/diff includes the custom title when --title is set', async () => {
+      const result = await startServer({
+        selection: { targetCommitish: 'HEAD', baseCommitish: 'HEAD^' },
+        preferredPort: 9035,
+        title: 'DEV-1234 review',
+      });
+      servers.push(result.server);
+
+      const response = await fetch(`http://localhost:${result.port}/api/diff`);
+      const data = (await response.json()) as any;
+
+      expect(response.ok).toBe(true);
+      expect(data).toHaveProperty('title', 'DEV-1234 review');
+    });
+
     it('GET /api/diff returns a JSON 500 on parse failure and does not poison subsequent requests', async () => {
       const parser = parserInstances.at(-1);
       parser?.parseDiff.mockClear();

src/server/server.ts

@@ -59,6 +59,7 @@ interface ServerOptions {
   diffMode?: DiffMode;
   repoPath?: string;
   contextLines?: number;
+  title?: string;
 }
 
 const GENERATED_STATUS_CACHE_TTL_MS = 60_000;
@@ -364,6 +365,7 @@ export async function startServer(
       requestedBaseMode,
       clearComments: options.clearComments,
       repositoryId,
+      title: options.title,
       commentImports: shouldIncludeCommentImports ? initialCommentImports : undefined,
       commentImportId: shouldIncludeCommentImports ? commentImportId : undefined,
     });

src/types/diff.ts

@@ -61,6 +61,7 @@ export interface DiffResponse {
   repositoryId?: string;
   commentImports?: CommentImport[];
   commentImportId?: string;
+  title?: string;
 }
 
 export interface GeneratedStatusResponse {