Category: Development

Test-Driven Development (TDD)

Guides development in vertical slices, one test and one implementation at a time, through red-green-refactor cycles.

Works with

Writes integration-style tests that verify behavior through public APIs
Uses vertical slices (one test, one implementation, repeat) instead of writing all tests first
Plans interface changes and test priorities before coding
Refactors (deduplication, deeper modules) only after tests pass

Use it when agent-written tests are shallow or break on every refactor.

Run the command below in your terminal. Pick the agents you use (Claude Code, Codex, Cursor, Gemini CLI, Copilot, and more) and it installs into the right folder.

npx skills add https://github.com/mattpocock/skills --skill tdd

To install manually, download the tdd skill folder from the GitHub repository and copy it into your agent's skills folder, such as ~/.claude/skills/ or .cursor/skills/.
Ask your agent for a related task and the skill is used automatically.

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