test-driven-development
Drives development with tests. Use when implementing any logic, fixing any bug, or changing any behavior. Use when you need to prove that code works, when a bug report arrives, or when you're about to modify existing functionality.
Install
git clone https://github.com/addyosmani/agent-skills /tmp/agent-skills && ln -s /tmp/agent-skills/skills/test-driven-development ~/.claude/skills/test-driven-developmentFrom README
Test-Driven Development Overview Write a failing test before writing the code that makes it pass. For bug fixes, reproduce the bug with a test before attempting a fix. Tests are proof — "seems right" is not done. A codebase with good tests is an AI agent's superpower; a codebase without tests is a liability. When to Use Implementing any new logic or behavior Fixing any bug (the Prove-It Pattern) Modifying existing functionality Adding edge case handling Any change that could break existing behavior When NOT to use: Pure configuration changes, documentation updates, or static content changes that have no behavioral impact. Related: For browser-based changes, combine TDD with runtime verification using Chrome DevTools MCP — see the Browser Testing section below. Discover the Stack First The TDD cycle is universal; the commands are not.
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