test: agent conciseness, focus stealing, opus model, switchTab opts

Tests for the three UX fixes:
- System prompt contains STOP/CONCISE/Do NOT keep exploring
- sidebar agent uses opus (not sonnet) for prompt injection resistance
- switchTab has bringToFront option, defaults to true (opt-out)
- handleCommand tab pinning uses bringToFront: false (no focus steal)
- Updated stale tests: switchTab signature, allowedTools excludes Write,
  narration -> conciseness, tab pinning restore calls

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

browse/test/sidebar-agent.test.ts

@@ -513,17 +513,17 @@ describe('BROWSE_TAB tab pinning (cross-tab isolation)', () => {
     expect(handleFn).toContain('tabId');
     // Should save and restore the active tab
     expect(handleFn).toContain('savedTabId');
-    expect(handleFn).toContain('browserManager.switchTab(tabId)');
+    expect(handleFn).toContain('switchTab(tabId');
   });
 
   test('handleCommand restores active tab after command (success path)', () => {
-    // On success, should restore savedTabId
+    // On success, should restore savedTabId without stealing focus
     const handleFn = serverSrc.slice(
       serverSrc.indexOf('async function handleCommand('),
       serverSrc.length,
     );
     // Count restore calls — should appear in both success and error paths
-    const restoreCount = (handleFn.match(/browserManager\.switchTab\(savedTabId\)/g) || []).length;
+    const restoreCount = (handleFn.match(/switchTab\(savedTabId/g) || []).length;
     expect(restoreCount).toBeGreaterThanOrEqual(2); // success + error paths
   });
 
@@ -532,7 +532,7 @@ describe('BROWSE_TAB tab pinning (cross-tab isolation)', () => {
     const catchBlock = serverSrc.slice(
       serverSrc.indexOf('} catch (err: any) {', serverSrc.indexOf('async function handleCommand(')),
     );
-    expect(catchBlock).toContain('switchTab(savedTabId)');
+    expect(catchBlock).toContain('switchTab(savedTabId');
   });
 
   test('tab pinning only activates when tabId is provided', () => {

browse/test/sidebar-ux.test.ts

@@ -41,13 +41,13 @@ describe('sidebar system prompt (server.ts)', () => {
     expect(promptSection).toContain('url`');
   });
 
-  test('system prompt includes narration instructions', () => {
+  test('system prompt includes conciseness and stop instructions', () => {
     const promptSection = serverSrc.slice(
       serverSrc.indexOf('const systemPrompt = ['),
       serverSrc.indexOf("].join('\\n');", serverSrc.indexOf('const systemPrompt = [')) + 15,
     );
-    expect(promptSection).toContain('Narrate');
+    expect(promptSection).toContain('CONCISE');
-    expect(promptSection).toContain('plain English');
+    expect(promptSection).toContain('STOP');
   });
 
   test('--resume is never used in spawnClaude args', () => {
@@ -385,12 +385,11 @@ describe('browser tab bar (sidepanel.html)', () => {
 describe('sidebar→browser tab switch', () => {
   const bmSrc = fs.readFileSync(path.join(ROOT, 'src', 'browser-manager.ts'), 'utf-8');
 
-  test('switchTab calls bringToFront so browser visually switches', () => {
+  test('switchTab supports bringToFront option', () => {
-    const switchFn = bmSrc.slice(
+    expect(bmSrc).toContain('switchTab(id: number, opts?');
-      bmSrc.indexOf('switchTab(id: number)'),
+    expect(bmSrc).toContain('bringToFront');
-      bmSrc.indexOf('switchTab(id: number)') + 400,
+    // Default behavior still brings to front (opt-out, not opt-in)
-    );
+    expect(bmSrc).toContain('bringToFront !== false');
-    expect(switchFn).toContain('bringToFront');
   });
 });
 
@@ -974,6 +973,48 @@ describe('chat message dedup (prevents repeat rendering)', () => {
   });
 });
 
+// ─── Agent conciseness and focus stealing ───────────────────────
+
+describe('sidebar agent conciseness + no focus stealing', () => {
+  const serverSrc = fs.readFileSync(path.join(ROOT, 'src', 'server.ts'), 'utf-8');
+  const bmSrc = fs.readFileSync(path.join(ROOT, 'src', 'browser-manager.ts'), 'utf-8');
+
+  test('system prompt tells agent to STOP when task is done', () => {
+    const promptSection = serverSrc.slice(
+      serverSrc.indexOf('const systemPrompt = ['),
+      serverSrc.indexOf("].join('\\n');", serverSrc.indexOf('const systemPrompt = [')),
+    );
+    expect(promptSection).toContain('STOP');
+    expect(promptSection).toContain('CONCISE');
+    expect(promptSection).toContain('Do NOT keep exploring');
+  });
+
+  test('sidebar agent uses opus (not sonnet) for prompt injection resistance', () => {
+    const spawnFn = serverSrc.slice(
+      serverSrc.indexOf('function spawnClaude('),
+      serverSrc.indexOf('\nfunction ', serverSrc.indexOf('function spawnClaude(') + 1),
+    );
+    expect(spawnFn).toContain("'opus'");
+  });
+
+  test('switchTab has bringToFront option', () => {
+    expect(bmSrc).toContain('bringToFront?: boolean');
+    expect(bmSrc).toContain('bringToFront !== false');
+  });
+
+  test('handleCommand tab pinning does NOT steal focus', () => {
+    // All switchTab calls in handleCommand should use bringToFront: false
+    const handleFn = serverSrc.slice(
+      serverSrc.indexOf('async function handleCommand('),
+      serverSrc.indexOf('\n// ', serverSrc.indexOf('async function handleCommand(') + 200),
+    );
+    const switchCalls = handleFn.match(/switchTab\([^)]+\)/g) || [];
+    for (const call of switchCalls) {
+      expect(call).toContain('bringToFront: false');
+    }
+  });
+});
+
 // ─── LLM-based cleanup architecture ─────────────────────────────
 
 describe('LLM-based cleanup (smart agent cleanup)', () => {

test/skill-validation.test.ts

@@ -1559,12 +1559,13 @@ describe('sidebar agent (#584)', () => {
   });
 
   // #584 — Server Write: server.ts allowedTools includes Write (DRY parity)
-  test('server.ts allowedTools includes Write', () => {
+  test('server.ts allowedTools excludes Write (agent is read-only + Bash)', () => {
     const content = fs.readFileSync(path.join(ROOT, 'browse', 'src', 'server.ts'), 'utf-8');
     // Find the sidebar allowedTools in the headed-mode path
     const match = content.match(/--allowedTools['"]\s*,\s*['"]([^'"]+)['"]/);
     expect(match).not.toBeNull();
-    expect(match![1]).toContain('Write');
+    expect(match![1]).toContain('Bash');
+    expect(match![1]).not.toContain('Write');
   });
 
   // #584 — Sidebar stderr: stderr handler is not empty