| name | skill-isolation-tester |
| description | Use PROACTIVELY when validating Claude Code skills before sharing or public release. Automated testing framework using multiple isolation environments (git worktree, Docker containers, VMs) to catch environment-specific bugs, hidden dependencies, and cleanup issues. Includes production-ready test templates and risk-based mode auto-detection. Not for functional testing of skill logic or non-skill code. |
Skill Isolation Tester
Tests Claude Code skills in isolated environments to ensure they work correctly without dependencies on your local setup.
When to Use
Trigger Phrases:
- "test skill [name] in isolation"
- "validate skill [name] in clean environment"
- "test my new skill in worktree/docker/vm"
- "check if skill [name] has hidden dependencies"
Use Cases:
- Test before committing or sharing publicly
- Validate no hidden dependencies on local environment
- Verify cleanup behavior (no leftover files/processes)
- Catch environment-specific bugs
Quick Decision Matrix
| Request | Mode | Isolation Level |
|---|
| "test in worktree" | Git Worktree | Fast, lightweight |
| "test in docker" | Docker | Full OS isolation |
| "test in vm" | VM | Complete isolation |
| "test skill X" (unspecified) | Auto-detect | Based on skill risk |
Risk-Based Auto-Detection
| Risk Level | Criteria | Recommended Mode |
|---|
| Low | Read-only, no system commands | Git Worktree |
| Medium | File creation, bash commands | Docker |
| High | System config changes, VM ops | VM |
Mode 1: Git Worktree (Fast)
Best for: Low-risk skills, quick iteration
Process:
- Create isolated git worktree
- Install Claude Code
- Copy skill and run tests
- Cleanup
Workflow: modes/mode1-git-worktree.md
Mode 2: Docker Container (Balanced)
Best for: Medium-risk skills, full OS isolation
Process:
- Build/pull Docker image
- Create container with Claude Code
- Run skill tests with monitoring
- Cleanup container and images
Workflow: modes/mode2-docker.md
Mode 3: VM (Safest)
Best for: High-risk skills, untrusted code
Process:
- Provision VM, take snapshot
- Install Claude Code
- Run tests with full monitoring
- Rollback or cleanup
Workflow: modes/mode3-vm.md
Test Templates
Production-ready templates in test-templates/:
| Template | Use For |
|---|
docker-skill-test.sh | Docker container/image skills |
docker-skill-test-json.sh | CI/CD with JSON/JUnit output |
api-skill-test.sh | HTTP/API calling skills |
file-manipulation-skill-test.sh | File modification skills |
git-skill-test.sh | Git operation skills |
Usage:
chmod +x test-templates/docker-skill-test.sh
./test-templates/docker-skill-test.sh my-skill-name
export JSON_ENABLED=true
./test-templates/docker-skill-test-json.sh my-skill-name
Helper Library
lib/docker-helpers.sh provides robust Docker testing utilities:
source ~/.claude/skills/skill-isolation-tester/lib/docker-helpers.sh
trap cleanup_on_exit EXIT
preflight_check_docker || exit 1
safe_docker_build "Dockerfile" "skill-test:my-skill"
safe_docker_run "skill-test:my-skill" bash -c "echo 'Testing...'"
Functions: validate_shell_command, retry_docker_command, cleanup_on_exit, preflight_check_docker, safe_docker_build, safe_docker_run
Validation Checks
Execution:
Side Effects:
Portability:
Test Report Format
# Skill Isolation Test Report: [skill-name]
## Environment: [Git Worktree / Docker / VM]
## Status: [PASS / FAIL / WARNING]
### Execution Results
✅ Skill completed successfully
### Side Effects Detected
⚠️ 3 temporary files not cleaned up
### Dependency Analysis
📦 Required: jq, git
### Overall Grade: B (READY with minor fixes)
Reference Materials
modes/mode1-git-worktree.md - Fast isolation workflow
modes/mode2-docker.md - Container isolation workflow
modes/mode3-vm.md - Full VM isolation workflow
data/risk-assessment.md - Skill risk evaluation
data/side-effect-checklist.md - Side effect validation
templates/test-report.md - Report template
test-templates/README.md - Template documentation
Quick Commands
test skill my-new-skill in isolation
test skill my-new-skill in worktree
test skill my-new-skill in docker
test skill my-new-skill in vm
Version: 0.1.0 | Author: Connor