Give each parallel coding agent its own git worktree, then review and merge

Details

Two ways to create the worktrees

	Claude Code	Plain git
Command	claude --worktree feature-auth	git worktree add ../project-feature-a -b feature-a
Location	.claude/worktrees/<name>/	Wherever you point it
Branch	worktree-<name>	The name you give
Base	Remote default branch; worktree.baseRef: "head" uses your local HEAD	Current HEAD, or a commit-ish you pass

Claude Code can also copy ignored files such as .env into each new worktree. List them in a .worktreeinclude file at the project root, using .gitignore syntax. A custom subagent gets its own worktree when its frontmatter says isolation: worktree. Add .claude/worktrees/ to .gitignore.

Worked example: three agents

I ran these plain git commands in a throwaway repository with one commit. Agent A and agent C edit the same line, on purpose.

1. Create three worktrees.

$ git worktree add ../wt-demo-a -b agent-a
Preparing worktree (new branch 'agent-a')
$ git worktree list
/tmp/wt-demo    b521497 [main]
/tmp/wt-demo-a  b521497 [agent-a]
/tmp/wt-demo-b  b521497 [agent-b]
/tmp/wt-demo-c  b521497 [agent-c]

2. Start one agent in each directory. Each one commits on its own branch.
3. Review from the main checkout, for example git log --oneline main..agent-a and git diff --stat main...agent-b.
4. Merge one branch at a time. A and B merged cleanly. C did not:

$ git merge --no-ff -m "Merge agent-c" agent-c
Auto-merging app.py
CONFLICT (content): Merge conflict in app.py
Automatic merge failed; fix conflicts and then commit the result.

I ran git merge --abort here. In real work, resolve the conflict, or ask agent C to rebase onto the new main.

5. Remove the worktrees. Git refuses if one is unclean:

$ git worktree remove ../wt-demo-c
fatal: '../wt-demo-c' contains modified or untracked files, use --force to delete it

Use --force only after you have saved what you need. Then delete merged branches with git branch -d. It refused for agent-c, "not fully merged", because that merge was aborted.

Git also refuses to check the same branch out in two worktrees: fatal: 'agent-a' is already used by worktree at '/tmp/wt-demo-a'.

What worktrees do not isolate

• The shared .git directory. Refs and repository config are shared. A git commit in one worktree writes to the same repository.
• Permission approvals. In Claude Code, "Yes, and don't ask again" saves the rule to the main checkout, so it applies in every worktree.
• Ports. Two dev servers on port 3000 still collide.
• Databases and caches outside the directory, such as a local database or a global package cache.
• Installed dependencies. A worktree is a fresh checkout, so run the install step in each one.
• The rest of your machine. Worktrees are not a security boundary. See run-coding-agent-safely-sandbox-container.

Common mistakes

• Giving two agents overlapping files, then merging late. Split tasks by file or module.
• Merging all branches at once. Merge one, rerun tests, then the next.
• Forgetting that worktree.baseRef defaults to the remote default branch, so unpushed local commits are missing.
• Deleting a worktree with --force before committing its work.