Worktree Agent Rules
Mandatory rules for any agent dispatched with isolation: "worktree".
Rule 1: Verify Your Working Directory
On start, run pwd. Your path MUST contain .claude/worktrees/.
If your CWD is the main repo path, STOP and report the error.
Rule 2: Create Feature Branch First
git checkout -b <branch-name>
Never commit on the default worktree-agent-* branch. Create your feature branch FIRST.
If git checkout -b <branch-name> fails with "a branch named X already exists":
# Option A: the branch has no commits beyond main — safe to reset and reuse
git branch -D <branch-name>
git checkout -b <branch-name>
# Option B: the branch is checked out in another active worktree — use a unique name
git checkout -b <branch-name>-2 # or append timestamp: $(date +%s)
If git checkout -b <branch-name> fails with "X is already used by worktree at Y":
# Branch is live in another worktree — use a unique suffix
git checkout -b <branch-name>-$(date +%s)
To update a branch held by another worktree (e.g. an existing PR branch): work detached from origin/<branch> and push with git push origin HEAD:<branch>. gh pr merge's post-merge local-checkout errors are harmless.
Rule 3: Use Worktree-Relative Paths
Never hardcode absolute paths from the main repo. Use $(git rev-parse --show-toplevel)/path.
Exception: Reading gitignored ADR files requires the main repo absolute path.
Rule 4: Ignore Auto-Plan Hooks
Keep planning inline instead of creating task_plan.md. If the auto-plan hook fires, continue with the current task and keep your attention on implementation.
Rule 5: Stage Specific Files Only
git add path/to/specific/file.py
Never git add ., git add -A, or git add --all. Verify with git diff --cached --stat.
Rule 6: Do Not Touch the Main Worktree
Never write to paths outside your worktree directory. Never run git checkout in the main repo.
Rule 7: Commit with Conventional Format
Use the commit message specified in your prompt. No attribution lines.
Rule 8: Run Both ruff Checks Before Declaring CI-Ready
For any Python code changes, run both checks before pushing or creating a PR:
ruff check . --config pyproject.toml
ruff format --check . --config pyproject.toml
Running only ruff check misses formatting violations. The Tests / lint CI job runs both — if you skip ruff format --check, the PR will fail CI and cannot merge due to branch protection.
Rule 9: Run Preflight Check on Start
Run the preflight script at the start of any worktree task to confirm clean state:
bash scripts/worktree-preflight.sh <intended-branch-name>
If it exits 1, fix the reported issue before proceeding.
Rule 10: Reserve disk capacity before creating a checkout
The dispatcher runs this before each implementation worktree:
python3 ~/.claude/skills/process/worktree-agent/scripts/worktree_capacity.py \
--repo "$(git rev-parse --show-toplevel)" --strict
The JSON report has three states:
| State | Dispatcher action |
|---|---|
ready (<80% used) |
Create the one implementation checkout for the candidate. |
cleanup-soon (80–<85%) |
Reclaim accepted clean checkouts before adding another. Use root read-only review work where possible. |
blocked (≥85%) |
Integrate, deploy, verify, or reclaim; create no new checkout. |
The report lists clean candidates only. The dispatcher confirms their task is inactive before removal because Git cleanliness alone does not prove that fact.
Rule 11: Assign checkout roles deliberately
| Task | Checkout policy |
|---|---|
| Source implementation or repair | One writable task worktree, reused through review corrections. |
| Code review, test-plan review, or read-only investigation | Read the candidate through git diff or git show from the repository root; allocate no checkout. |
| Large repository implementation | Create a sparse worktree containing declared source/test/config scopes; include whole-repository content only when the task requires it. |
For a sparse implementation checkout:
git worktree add --no-checkout <worktree-path> -b <branch> <base-sha>
git -C <worktree-path> sparse-checkout init --no-cone
git -C <worktree-path> sparse-checkout set --no-cone <declared-path>...
git -C <worktree-path> checkout
Record any full-checkout reason in the dispatch handoff.
Post-Merge Cleanup
After integration or a PR merge, the dispatcher first confirms that the task is inactive and the checkout is clean, then runs:
git worktree remove -- <accepted-worktree-path>
bash scripts/worktree-cleanup.sh --force
git worktree remove frees the materialized checkout while preserving its branch for recovery. The cleanup script then prunes stale .git/worktrees entries and removes merged harness branches.
Failure Modes This Prevents
| Failure | Rule | Without It |
|---|---|---|
| Agent edits main repo files | 1, 6 | Changes leak to main, get stashed/lost |
| Context wasted on task_plan.md | 4 | Implementation budget consumed by planning |
| Commit on wrong branch | 2 | Orchestrator merges wrong content |
| PR has changes from 2 ADRs | 5, 6 | Cross-contamination between agents |
| Branch locked by worktree | 2 | Fatal error on checkout |
| PR fails CI on format | 8 | Merge blocked; ruff format --check was skipped |
| New task fails to create worktree | 9 | Branch name collision from prior stale run |