tdd-red-green-refactor

What problem does it solve? AI-assisted coding often produces large, unverified code blocks written in one pass, making it hard to confirm correctness or catch regressions. This Skill imposes a disciplined Red-Green-Refactor loop so every line of code is backed by a failing-then-passing test. ## Core Features & Use Cases - Three-Phase Cycle Enforcement: Guides the AI through Red (write one failing test), Green (minimal passing implementation), and Refactor (clean up while tests stay green). - Incremental Test Discipline: Forbids writing multiple tests at once, requiring a strict one-test, one-fix loop for every sub-feature. - Test Integrity Protection: Prevents modifying existing tests just to make failing implementations pass, using TypeScript typing and assertions as backpressure. - Use Case: When adding a new utility function to a Node.js service, the AI writes a single Vitest test, watches it fail, implements the minimal code to pass, then refactors with full type safety. ## Quick Start Use the TDD skill to implement a new string-reversal utility in TypeScript with Vitest, following the red-green-refactor cycle one test at a time.