PR: https://git.cafe/pingdotgg/t3code/pulls/27815
GitHub: https://github.com/pingdotgg/t3code/pull/27815
Tested on Linux with /usr/bin/google-chrome and repository Playwright 1.60.0.
No mocks, fixtures, replay provider, or direct database writes.
Projects and threads were created through the web UI. Git setup and inspection
ran through real Codex gpt-6.1-sol turns in the running development app.

BEFORE: github/main 5fe18d79ac
$ git worktree add ../main github/main
$ vp i
$ T3CODE_DEV_SEED=0 vp run dev  (background, captured PID 15245)
[dev-runner] serverPort=16733 webPort=8693 baseDir=/home/user/main/.t3
UI: Add project > New project > rename-verification.
Codex: commit README.md and create local t3 branch while staying on main.
UI: New thread in rename-verification > New worktree > send inspection prompt.
Codex gpt-6.1-sol: git branch --show-current => t3-548127d2
Codex gpt-6.1-sol: git branch --list => main, t3, t3-548127d2
Server warning: Thread worktree branch rename failed
GitCommandError: Git command failed in GitVcsDriver.renameBranch
(/home/user/main/.t3/worktrees/rename-verification/t3-548127d2): git branch rename failed
UI remained on t3-548127d2 after the provider turn completed.
Stopped main's captured process group before starting the PR server.

AFTER: exact PR head 14831d5b95a92530d09a7c300327686a48e33367
$ vp i
$ T3CODE_DEV_SEED=0 vp run dev --home-dir /home/user/t3code/.t3
  (background, captured PID 21075)
[dev-runner] serverPort=13773 webPort=5733 baseDir=/home/user/t3code/.t3
UI: Add project > Local folder > same rename-verification repository.
UI: New worktree > same inspection prompt > Codex gpt-6.1-sol.
Codex: git branch --show-current => t3-inspect-branch-rename
Codex: git branch --list includes t3 and t3-inspect-branch-rename
Codex: cat README.md => # Rename verification
UI sidebar and Version Control show t3-inspect-branch-rename.

NEIGHBOR: exact and descendant collisions
Codex created t3-fix-login and t3-fix-login-1/child at HEAD.
UI: New worktree > prompt requesting fix-login descriptive branch fragment.
Initial Codex command ran before the asynchronous rename and saw t3-458d9366.
UI then changed to t3-fix-login-2.
A second real Codex turn after rename ran git branch --show-current:
t3-fix-login-2
Its git branch --list confirmed all of:
  t3
  t3-fix-login
  t3-fix-login-1/child
* t3-fix-login-2
Host read-only cross-check:
$ git -C /home/user/t3code/.t3/worktrees/rename-verification/t3-458d9366 branch --show-current
t3-fix-login-2

NEIGHBOR: normal nonconflicting naming
UI: Add project > New project > rename-normal (no local t3 branch).
UI: New worktree > same inspection prompt > Codex gpt-6.1-sol.
Codex: git branch --show-current => t3/inspect-branch-rename
Codex: git branch --list => main, t3/inspect-branch-rename
Codex successfully read the app-created README.md.
Host read-only cross-check:
$ git -C /home/user/t3code/.t3/worktrees/rename-normal/t3-1e08a3f6 status --short --branch
## t3/inspect-branch-rename

CHECKS (Blacksmith remote runner, exact PR head):
$ vp i
$ vp test run apps/server/src/vcs/GitVcsDriverCore.test.ts
Test Files  1 passed (1)
Tests       197 passed (197)
Includes real-git parent-path, exact collision, descendant collision, and
exactName preservation cases. Remote runner stopped after the check.
GitCafe reported 28 successful, 0 failing, 0 pending contexts.
Direct GitHub refresh: 20 success, 8 skipped, 1 cancelled (Native fingerprint diff),
0 failing or pending. No CI rerun was requested for this verification-only pass.
No code changes, commits, or pushes were necessary.

NOT VERIFIED:
Native desktop/iOS/Android clients; macOS/Windows git behavior; tunnel/relay
connections; other providers; custom naming settings through the UI.
Only the Linux dev web client and local server with Codex were exercised.