fix: surface worktree identity in session badge

The footer project chip previously kept showing only the source project and selected branch even after a session launched inside an isolated CLI worktree. That made an active worktree session look identical to a normal checkout, especially while agent tools were already operating under .claude/worktrees. The server now returns explicit worktree metadata from the session launch intent, and the desktop chip preserves the user-facing project and branch while appending the isolated worktree slug.

Constraint: CLI worktree branches are internal implementation details and should not replace the user-selected branch label.

Rejected: Show only the actual worktree git branch | it would expose worktree-desktop-* internals and make the business branch harder to read.

Confidence: high

Scope-risk: narrow

Directive: Keep normal checkout footer rendering unchanged; only add worktree identity when session metadata says isolation is enabled.

Tested: bun test src/server/__tests__/sessions.test.ts --test-name-pattern git-info

Tested: cd desktop && bun run test -- src/components/shared/ProjectContextChip.test.tsx

Tested: cd desktop && bun run lint

Tested: git diff --check

desktop/src/api/sessions.ts

@@ -8,6 +8,21 @@ type MessagesResponse = {
   taskNotifications?: AgentTaskNotification[]
 }
 type CreateSessionResponse = { sessionId: string; workDir?: string }
+export type SessionGitWorktreeInfo = {
+  enabled: boolean
+  path: string | null
+  plannedPath: string | null
+  sourceWorkDir: string | null
+  slug: string | null
+  branch: string | null
+}
+export type SessionGitInfo = {
+  branch: string | null
+  repoName: string | null
+  workDir: string
+  changedFiles: number
+  worktree: SessionGitWorktreeInfo | null
+}
 export type CreateSessionRepositoryOptions = {
   branch?: string | null
   worktree?: boolean
@@ -309,7 +324,7 @@ export const sessionsApi = {
   },
 
   getGitInfo(sessionId: string) {
-    return api.get<{ branch: string | null; repoName: string | null; workDir: string; changedFiles: number }>(`/api/sessions/${sessionId}/git-info`)
+    return api.get<SessionGitInfo>(`/api/sessions/${sessionId}/git-info`)
   },
 
   getSlashCommands(sessionId: string) {

desktop/src/components/chat/ChatInput.tsx

@@ -12,7 +12,7 @@ import {
   useWorkspaceChatContextStore,
   type WorkspaceChatReference,
 } from '../../stores/workspaceChatContextStore'
-import { sessionsApi } from '../../api/sessions'
+import { sessionsApi, type SessionGitInfo } from '../../api/sessions'
 import { PermissionModeSelector } from '../controls/PermissionModeSelector'
 import { ModelSelector } from '../controls/ModelSelector'
 import type { AttachmentRef } from '../../types/chat'
@@ -30,7 +30,7 @@ import {
   resolveSlashUiAction,
 } from './composerUtils'
 
-type GitInfo = { branch: string | null; repoName: string | null; workDir: string; changedFiles: number }
+type GitInfo = SessionGitInfo
 
 type Attachment = {
   id: string
@@ -981,6 +981,10 @@ export function ChatInput({ variant = 'default', compact = false }: ChatInputPro
                 workDir={resolvedWorkDir}
                 repoName={gitInfo?.repoName || null}
                 branch={gitInfo?.branch || null}
+                sourceWorkDir={gitInfo?.worktree?.sourceWorkDir || null}
+                isWorktree={!!gitInfo?.worktree?.enabled}
+                worktreeSlug={gitInfo?.worktree?.slug || null}
+                worktreePath={gitInfo?.worktree?.path || gitInfo?.worktree?.plannedPath || null}
                 compact={compact}
               />
             ) : (

desktop/src/components/shared/ProjectContextChip.test.tsx

@@ -0,0 +1,37 @@
+import { render, screen } from '@testing-library/react'
+import { describe, expect, it } from 'vitest'
+import '@testing-library/jest-dom'
+import { ProjectContextChip } from './ProjectContextChip'
+
+describe('ProjectContextChip', () => {
+  it('keeps the source project label and adds worktree identity', () => {
+    render(
+      <ProjectContextChip
+        workDir="/workspace/OpenCutSkill/.claude/worktrees/desktop-main-54a09f85"
+        sourceWorkDir="/workspace/OpenCutSkill"
+        repoName={null}
+        branch="main"
+        isWorktree
+        worktreeSlug="desktop-main-54a09f85"
+      />,
+    )
+
+    expect(screen.getByText('OpenCutSkill')).toBeInTheDocument()
+    expect(screen.getByText('main')).toBeInTheDocument()
+    expect(screen.getByText('worktree')).toBeInTheDocument()
+    expect(screen.getByText('desktop-main-54a09f85')).toBeInTheDocument()
+  })
+
+  it('does not show worktree details for a normal checkout', () => {
+    render(
+      <ProjectContextChip
+        workDir="/workspace/OpenCutSkill"
+        repoName={null}
+        branch="main"
+      />,
+    )
+
+    expect(screen.getByText('OpenCutSkill')).toBeInTheDocument()
+    expect(screen.queryByText('worktree')).not.toBeInTheDocument()
+  })
+})

desktop/src/components/shared/ProjectContextChip.tsx

@@ -2,16 +2,43 @@ type Props = {
   workDir?: string | null
   repoName?: string | null
   branch?: string | null
+  sourceWorkDir?: string | null
+  isWorktree?: boolean
+  worktreeSlug?: string | null
+  worktreePath?: string | null
   compact?: boolean
 }
 
-export function ProjectContextChip({ workDir, repoName, branch, compact = false }: Props) {
-  const label = branch ? (repoName || workDir?.split('/').pop() || '') : (workDir?.split('/').pop() || repoName || '')
+function basename(path: string | null | undefined): string {
+  return path?.split('/').filter(Boolean).pop() || ''
+}
+
+export function ProjectContextChip({
+  workDir,
+  repoName,
+  branch,
+  sourceWorkDir,
+  isWorktree = false,
+  worktreeSlug,
+  worktreePath,
+  compact = false,
+}: Props) {
+  const labelRoot = isWorktree ? (sourceWorkDir || workDir) : workDir
+  const label = branch ? (repoName || basename(labelRoot)) : (basename(labelRoot) || repoName || '')
+  const worktreeName = worktreeSlug || basename(worktreePath) || 'isolated'
+  const title = [
+    label,
+    branch ? `branch: ${branch}` : null,
+    isWorktree ? `worktree: ${worktreeName}` : null,
+    worktreePath ? `worktree cwd: ${worktreePath}` : null,
+    workDir ? `cwd: ${workDir}` : null,
+  ].filter(Boolean).join('\n')
 
   if (!label) return null
 
   return (
     <div
+      title={title}
       className={`inline-flex max-w-full items-center rounded-full border border-[var(--color-border)] bg-[var(--color-surface-container-lowest)] text-[var(--color-text-secondary)] ${
         compact ? 'gap-1.5 px-3 py-1.5 text-xs' : 'gap-2 px-4 py-2 text-sm'
       }`}
@@ -30,6 +57,15 @@ export function ProjectContextChip({ workDir, repoName, branch, compact = false
           <span className="truncate">{branch}</span>
         </>
       ) : null}
+      {isWorktree ? (
+        <>
+          <span className="text-[var(--color-text-tertiary)]">|</span>
+          <span className="shrink-0 rounded-full border border-[var(--color-border)] px-1.5 py-0.5 text-[10px] font-medium uppercase leading-none text-[var(--color-text-tertiary)]">
+            worktree
+          </span>
+          <span className="max-w-[12rem] truncate">{worktreeName}</span>
+        </>
+      ) : null}
     </div>
   )
 }

src/server/__tests__/sessions.test.ts

@@ -1508,6 +1508,53 @@ describe('Sessions API', () => {
     }
   })
 
+  it('GET /api/sessions/:id/git-info should include isolated worktree identity', async () => {
+    const workDir = await createCleanGitRepo(tmpDir)
+    const { sessionId } = await sessionService.createSession(
+      workDir,
+      { branch: 'main', worktree: true },
+    )
+    const launchInfo = await sessionService.getSessionLaunchInfo(sessionId)
+    const repository = launchInfo?.repository
+    expect(repository?.worktreePath).toBeTruthy()
+    expect(repository?.worktreeBranch).toBeTruthy()
+
+    const activeWorktree = repository!.worktreePath!
+    git(workDir, 'worktree', 'add', '-b', repository!.worktreeBranch!, activeWorktree, 'main')
+    const sessionsMap = (conversationService as any).sessions as Map<string, { workDir: string }>
+
+    sessionsMap.set(sessionId, { workDir: activeWorktree })
+    try {
+      const res = await fetch(`${baseUrl}/api/sessions/${sessionId}/git-info`)
+      expect(res.status).toBe(200)
+
+      const body = (await res.json()) as {
+        branch: string | null
+        workDir: string
+        worktree: {
+          enabled: boolean
+          path: string | null
+          plannedPath: string | null
+          sourceWorkDir: string | null
+          slug: string | null
+          branch: string | null
+        } | null
+      }
+      expect(body.branch).toBe('main')
+      expect(body.workDir).toBe(activeWorktree)
+      expect(body.worktree).toEqual({
+        enabled: true,
+        path: activeWorktree,
+        plannedPath: activeWorktree,
+        sourceWorkDir: repository!.requestedWorkDir,
+        slug: repository!.worktreeSlug,
+        branch: repository!.worktreeBranch,
+      })
+    } finally {
+      sessionsMap.delete(sessionId)
+    }
+  })
+
   it('DELETE /api/sessions/:id should delete the session', async () => {
     const sessionId = 'aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee'
     await writeSessionFile('-tmp-api-test', sessionId, [makeSnapshotEntry()])

src/server/api/sessions.ts

@@ -539,7 +539,18 @@ async function getGitInfo(sessionId: string): Promise<Response> {
     throw ApiError.notFound(`Session not found: ${sessionId}`)
   }
   const launchInfo = await sessionService.getSessionLaunchInfo(sessionId).catch(() => null)
-  const sessionBranch = launchInfo?.repository?.branch || null
+  const repository = launchInfo?.repository
+  const sessionBranch = repository?.branch || null
+  const worktree = repository?.worktree
+    ? {
+        enabled: true,
+        path: workDir,
+        plannedPath: repository.worktreePath || null,
+        sourceWorkDir: repository.requestedWorkDir || repository.repoRoot || null,
+        slug: repository.worktreeSlug || null,
+        branch: repository.worktreeBranch || null,
+      }
+    : null
 
   try {
     // Get branch name
@@ -584,6 +595,7 @@ async function getGitInfo(sessionId: string): Promise<Response> {
       repoName,
       workDir,
       changedFiles,
+      worktree,
     })
   } catch {
     // Not a git repo or git not available
@@ -592,6 +604,7 @@ async function getGitInfo(sessionId: string): Promise<Response> {
       repoName: null,
       workDir,
       changedFiles: 0,
+      worktree,
     })
   }
 }