Expert guidance for writing resilient end-to-end tests that span multiple processes and components. Use this skill when reviewing, writing, or refactoring system-wide e2e tests. Covers user-facing scenarios, helper functions, data factories, ARIA-based selectors, and auto-retriable assertions. NOT for unit/integration tests - use testing-unit-integration skill instead. See references/playwright-resilience.md for detailed selector patterns.
Expert guidance for writing clean, simple, and effective unit, integration, component, microservice, and API tests. Use this skill when reviewing existing tests for violations, writing new tests, or refactoring tests. NOT for end-to-end tests that span multiple processes - use testing-e2e skill instead. Covers AAA pattern, data factories, mocking strategies, DOM testing, database testing, and assertion best practices.
Expert guidance for creating effective Claude Code agents (subagents). Use when users want to create a new agent, update an existing agent, or learn agent design best practices. Covers agent architecture, prompt engineering, tool selection, model choice, and common pitfalls. Integrates with skill-creator when agent needs accompanying skills.
Expert guidance for creating, updating, and maintaining CLAUDE.md memory files following best practices for hierarchical memory, structure, content organization, and team collaboration