Git Worktree skill

Git Worktrees for Parallel Agents

In Cloudroom ($ROOM_THREAD_ID is set)

Never run git worktree add yourself. Cloudroom only deletes worktrees it made, so hand-made ones pile up in ~/code forever.

• New task: start the thread with New worktree instead.

• Move this thread to its own worktree: fork it into a Cloudroom-managed worktree. Cloudroom makes the branch and deletes the folder once its last thread is archived (after the worktree retention setting, default 21 days).

  room-cli thread fork "$ROOM_THREAD_ID" --new-environment worktree --title "<task>" \
    --prompt "You now run in a new worktree. Copy the gitignored .env files from <primary checkout> into it, then stop and wait for the user."
  

  It branches from main, so uncommitted edits stay behind; commit them first or pass --base-branch <ref>. Then tell the user to continue in the new thread and archive this one. Skip the rest of this skill.

Start here

Detect where you are before editing:

[ "$(git rev-parse --path-format=absolute --git-dir)" = "$(git rev-parse --path-format=absolute --git-common-dir)" ] \
  && echo "primary checkout" || echo "worktree"

• Primary checkout → create a task-named worktree, complete the setup below, and cd into it before editing.
• Worktree (including one created by Cursor) → proceed with the task.

Working model

Worktrees have separate working files and branches but share Git history, stashes, config, and refs.

• One task = one worktree = one agent session. Never share a working directory between agents.
• Keep the primary checkout on main, only for review, merging, and pushing.
• Nothing auto-merges. The human reviews each diff before merging or discarding the worktree.
• Keep task branches local and short-lived. Push only main unless the user explicitly asks to push a task branch.
• Merge one worktree at a time. If main moved, rebase the task branch before merging.

Creating and removing

git worktree add ../myrepo-task-x          # new worktree + branch "myrepo-task-x"
git worktree add ../fix-y -b fix-y main    # explicit branch off main
git worktree list                          # see all worktrees
git worktree remove ../myrepo-task-x       # delete when merged/abandoned
git worktree prune                         # clean up stale registrations

A branch can be checked out in only one worktree, including main.

In Cursor, use the Agents Window or /worktree <task>. /apply-worktree applies results to the main checkout; /delete-worktree discards them. /best-of-n model1,model2 <task> runs the same task in parallel worktrees, one per model. Cursor auto-deletes older worktrees, so preserve results promptly; pushing task branches still requires explicit approval.

Complete the setup

A fresh worktree contains tracked files only. Bootstrap it before task work:

1. Env/secret files — copy .env, .env.local, and similar files from the primary checkout. Never symlink them: edits would change the originals.
2. Dependencies — install locally (npm ci, pnpm install, uv sync, bundle install). Never symlink node_modules from the primary checkout: bundlers such as Next.js/Turbopack reject paths outside the worktree. If it is a symlink, remove it with rm -f node_modules and install normally.
3. Databases and services — choose shared or per-worktree state. For shared services, pin their identity to avoid duplicate instances and port conflicts. For shared Docker Compose services, pin the project name, for example with a top-level name:; otherwise each worktree's folder name creates a separate project. Copy or re-seed per-worktree state such as SQLite files.
4. Ports — run dev/test servers and debuggers one at a time, or configure separate ports per worktree.
5. Generated files and caches — rebuild gitignored output in the worktree (npm run build, codegen).
6. Git hooks — core.hooksPath and .git/config are shared; verify hook scripts don't assume the primary checkout's path.

Automate setup

In Cursor, .cursor/worktrees.json runs setup on creation ($ROOT_WORKTREE_PATH is the primary checkout):

{
  "setup-worktree": [
    "npm ci",
    "cp $ROOT_WORKTREE_PATH/.env.local .env.local"
  ]
}

Otherwise, put the checklist in scripts/setup-worktree.sh and run it first in each new worktree. Find the primary checkout from a worktree with:

dirname "$(git rev-parse --path-format=absolute --git-common-dir)"

Merge and clean up

# from the primary checkout, after reviewing the worktree's diff:
git merge --no-ff task-branch     # or: git merge --squash task-branch
git worktree remove ../myrepo-task-x
git branch -d task-branch

In Cursor, use /apply-worktree, then review and commit.

• Delete each worktree as soon as its branch is merged or pushed to main. Nothing else cleans them up.
• Rebase or restart worktrees that have stalled for days.
• Commit early and often. Deleting a worktree loses uncommitted work; commits remain in the shared repository.