using-git-worktrees

name	using-git-worktrees
description	Use when starting feature work that needs isolation from current workspace or before executing implementation plans - creates isolated git worktrees with smart directory selection and safety verification

Using Git Worktrees

Overview

Git worktrees create isolated workspaces sharing the same repository, allowing work on multiple branches simultaneously without switching.

Core principle: Systematic directory selection + safety verification = reliable isolation.

Announce at start: "I'm using the using-git-worktrees skill to set up an isolated workspace."

---

⛔ MANDATORY — Worktree Creation Checklist

创建 worktree 后、开始任何工作之前，必须完成以下全部项目：

• 目录选择 — 按优先级：existing .worktrees/ > CLAUDE.md > ask user
• 验证 gitignore — git check-ignore 确认目录被忽略（project-local 时）
• 创建 worktree — git worktree add <path> -b <branch>
• 切换工作区 — 使用 change_workspace 工具，不是 cd
• 安装依赖 — go mod download / npm install 等
• 验证基线 — go test ./... 或等效命令，确保测试全部通过
• 报告位置 — 向用户报告路径、测试结果、准备就绪

只有全部通过才开始 feature 工作。 基线测试失败时必须报告并询问是否继续。

Directory Selection Process

Follow this priority order:

1. Check Existing Directories

# Check in priority order
ls -d .worktrees 2>/dev/null     # Preferred (hidden)
ls -d worktrees 2>/dev/null      # Alternative

If found: Use that directory. If both exist, .worktrees wins.

2. Check CLAUDE.md

grep -i "worktree.*director" CLAUDE.md 2>/dev/null

If preference specified: Use it without asking.

3. Ask User

If no directory exists and no CLAUDE.md preference:

No worktree directory found. Where should I create worktrees?

1. .worktrees/ (project-local, hidden)
2. ~/.config/superpowers/worktrees/<project-name>/ (global location)

Which would you prefer?

Safety Verification

For Project-Local Directories (.worktrees or worktrees)

MUST verify directory is ignored before creating worktree:

# Check if directory is ignored (respects local, global, and system gitignore)
git check-ignore -q .worktrees 2>/dev/null || git check-ignore -q worktrees 2>/dev/null

If NOT ignored:

Per Jesse's rule "Fix broken things immediately":

1. Add appropriate line to .gitignore
2. Commit the change
3. Proceed with worktree creation

Why critical: Prevents accidentally committing worktree contents to repository.

For Global Directory (~/.config/superpowers/worktrees)

No .gitignore verification needed - outside project entirely.

Creation Steps

1. Detect Project Name

project=$(basename "$(git rev-parse --show-toplevel)")

2. Create Worktree

# Determine full path
case $LOCATION in
  .worktrees|worktrees)
    path="$LOCATION/$BRANCH_NAME"
    ;;
  ~/.config/superpowers/worktrees/*)
    path="~/.config/superpowers/worktrees/$project/$BRANCH_NAME"
    ;;
esac

# Create worktree with new branch
git worktree add "$path" -b "$BRANCH_NAME"

# IMPORTANT: After creating the worktree, use the change_workspace tool
# This switches the agent's workspace to the new worktree directory.
# All subsequent file operations (read, write, grep, edit, bash) will be relative to the new workspace.
#
# Example tool call:
# <change_workspace path="$path"/>
#
# DO NOT use 'cd' in bash - it only affects the bash subprocess, not the agent's workspace.

### 3. Run Project Setup

Auto-detect and run appropriate setup:

```bash
# Node.js
if [ -f package.json ]; then npm install; fi

# Rust
if [ -f Cargo.toml ]; then cargo build; fi

# Python
if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
if [ -f pyproject.toml ]; then poetry install; fi

# Go
if [ -f go.mod ]; then go mod download; fi

4. Verify Clean Baseline

Run tests to ensure worktree starts clean:

# Examples - use project-appropriate command
npm test
cargo test
pytest
go test ./...

If tests fail: Report failures, ask whether to proceed or investigate.

If tests pass: Report ready.

5. Report Location

Worktree ready at <full-path>
Tests passing (<N> tests, 0 failures)
Ready to implement <feature-name>

Quick Reference

Situation	Action
.worktrees/ exists	Use it (verify ignored)
worktrees/ exists	Use it (verify ignored)
Both exist	Use .worktrees/
Neither exists	Check CLAUDE.md → Ask user
Directory not ignored	Add to .gitignore + commit
Tests fail during baseline	Report failures + ask
No package.json/Cargo.toml	Skip dependency install

Common Mistakes

Skipping ignore verification

• Problem: Worktree contents get tracked, pollute git status
• Fix: Always use git check-ignore before creating project-local worktree

Assuming directory location

• Problem: Creates inconsistency, violates project conventions
• Fix: Follow priority: existing > CLAUDE.md > ask

Proceeding with failing tests

• Problem: Can't distinguish new bugs from pre-existing issues
• Fix: Report failures, get explicit permission to proceed

Hardcoding setup commands

• Problem: Breaks on projects using different tools
• Fix: Auto-detect from project files (package.json, etc.)

Example Workflow

You: I'm using the using-git-worktrees skill to set up an isolated workspace.

[Check .worktrees/ - exists]
[Verify ignored - git check-ignore confirms .worktrees/ is ignored]
[Create worktree: git worktree add .worktrees/auth -b feature/auth]
[Use change_workspace tool: change_workspace path=".worktrees/auth"]
[Run npm install in the new workspace]
[Run npm test - 47 passing]

Worktree ready at /Users/jesse/myproject/.worktrees/auth
Tests passing (47 tests, 0 failures)
Ready to implement auth feature

Red Flags

Never:

• Create worktree without verifying it's ignored (project-local)
• Skip baseline test verification
• Proceed with failing tests without asking
• Assume directory location when ambiguous
• Skip CLAUDE.md check

Always:

• Follow directory priority: existing > CLAUDE.md > ask
• Verify directory is ignored for project-local
• Auto-detect and run project setup
• Verify clean test baseline

Integration

Called by:

• brainstorming (Phase 4) - REQUIRED when design is approved and implementation follows
• subagent-driven-development - REQUIRED before executing any tasks
• executing-plans - REQUIRED before executing any tasks
• Any skill needing isolated workspace

Pairs with:

• finishing-a-development-branch - REQUIRED for cleanup after work complete
• subagent - Combine for persistent, observable task execution with ai serve

Agent Worktrees

Combine git worktrees with subagent 技能 for persistent, observable task execution in isolated environments.

When to Use

Scenario	Approach	Why
Long-running analysis	Worktree + subagent	Results persist in worktree after completion
Parallel feature work	Multiple worktrees	Isolated branches, no conflicts
Code review before merge	Worktree + review agent	Read-only review in isolated environment
Experimental changes	Worktree + coder agent	Safely iterate without affecting main branch

Workflow

# 1. Create worktree for the task
git worktree add .worktrees/review-auth -b review/auth

2. 用 subagent 技能 spawn 子 agent，参数：

参数	值
system-prompt	@/path/to/reviewer.md
input	'Review auth changes for security issues'
name	review-auth
timeout	15m

3. 用 subagent 技能 Watch 等待完成
4. 用 subagent 技能 Cleanup 清理 agent
5. 结果保留在 worktree 中供检查

Pattern: Persistent Review Session

git worktree add .worktrees/review-feature-x -b review/feature-x

用 subagent 技能 spawn + watch，参数：

参数	值
system-prompt	@/path/to/reviewer.md
input	'Review changes against main: security, correctness, style'
name	review-feature-x
timeout	15m

完成后 Cleanup。Worktree 保留，可用于手动检查、追加 review、测试。

Pattern: Parallel Feature Branches

git worktree add .worktrees/feature-auth -b feature/auth
git worktree add .worktrees/feature-api -b feature/api

用 subagent 技能并行 spawn 2 个 agent（注意并发上限），参数：

Agent	system-prompt	input	name	timeout
Auth	@/path/to/builder.md	'Implement auth feature in current worktree'	build-auth	15m
API	@/path/to/builder.md	'Implement API feature in current worktree'	build-api	15m

完整 spawn/watch/cleanup 代码见 subagent 技能。每个 worktree 中的改动互不干扰，可独立 merge。

Benefits Over Temporary Agents

Temporary Agent	Worktree Agent
Results lost after completion	Results persist in worktree
Hard to inspect intermediate state	Full git history available
Difficult to debug failures	Can check worktree state and git diff
Single-shot execution	Can spawn new agents and iterate

Cleanup

After task completion, use the finishing-a-development-branch skill to clean up worktrees.

See also: subagent skill for ai serve/send/watch/kill pattern details