“vitest-expert” is a ready-made agent for Testing and quality, built for Claude Code, Codex, Cursor. Download the file, or use “Make a custom version” to add your project details so the AI works exactly for your project.
The agent reads this file only when a related task comes up; so keeping it in the project costs nothing.
Use describe blocks to group related tests logically
Prefer async/await for handling asynchronous code
Use beforeEach and afterEach hooks for setup/teardown
Mock external dependencies to isolate test subjects
Utilize Vitest's snapshot testing for UI components
Leverage Vitest's built-in assertions for clarity
Configure Vitest to run specific test files or directories
Use .only and .skip to focus on specific tests
Integrate Vitest seamlessly with version control hooks
Maintain a separate vitest.config.js for test-specific configuration
Quality Checklist
All tests should be deterministic and stable
Ensure high coverage with meaningful tests
Avoid testing implementation details; focus on behavior
Provide clear and descriptive test names
Regularly refactor tests to remove duplication
Continuously review and update mocks and stubs
Optimize test run times without sacrificing coverage
Consistently review and prune outdated tests
Ensure compatibility with multiple Node.js versions
Document test rationale and methodology clearly
Output
A comprehensive suite of tests covering all critical paths
Structured test files with logical organization
Detailed test reports with coverage metrics
Maintained and updated vitest snapshots
Clean test directory with no orphan or obsolete files
Documented test cases with clear descriptions
Efficient execution with minimal global side effects
Configuration files for customizing test environments
Established CI/CD workflows for automated testing
Secure and isolated testing environments for reliability
Build a custom version for your project
Write your project details; to the end of Agent is added, and you get a file that is given to the AI without extra explanation. Everything is built in your browser and no data goes to the server.
Team projects: commit the file to the repository so every agent on the team follows the same rules. With Build a bundle Get several skills together, with the correct structure.
Frequently asked questions
Agent “vitest-expert” — where do I put it?
for Claude Code in .claude/skills/vitest-expert/SKILL.md, for Codex in .agents/skills, for Copilot in .github/skills and for Cursor in .cursor/skills or .cursor/rules. Use the “Build a bundle” button to get a zip with the correct structure.
Can I modify it for my own project?
Yes. The license MIT allows modification and commercial use. With “Build a custom version” your project's details are added to the file, and you can edit the text afterward.
This Agent Which tools does it work with?
With Claude Code, Codex, Cursor, Gemini CLI. Standard Agent Skills are read by all modern coding agents.
Toolkit for interacting with and testing local web applications using Playwright. Supports verifying frontend functionality, debugging UI behavior, capturing browser screenshots, and viewing browser logs.
Capture screenshots of web apps during development using Playwright and PIL. Supports full-page captures, interactive states, and an iterate-on-crop workflow that avoids slow re-screenshots.
Toolkit for interacting with and testing local web applications using Playwright. Supports verifying frontend functionality, debugging UI behavior, capturing browser screenshots, and viewing browser logs.
Run a read-only audit for missing, weak, stale, or mis-scoped test coverage. If the user does not name a scope, audit the full repository and identify important code paths, routes,…
