What problem does it solve? Developers often write code first and add tests afterward, which produces tests that pass immediately and prove nothing about correctness. This Skill enforces strict test-driven development discipline so every piece of production code is backed by a test that was watched failing first. ## Core Features & Use Cases - RED-GREEN-REFACTOR Enforcement: Guides the agent through writing a failing test, verifying the failure, writing minimal passing code, and refactoring safely. - Rationalization Detection: Lists common excuses for skipping TDD and red flags that trigger a restart of the cycle. - Subagent Integration: Provides templates for delegating implementation tasks with TDD requirements via delegate_task and the terminal tool. - Use Case: When fixing a bug, the agent first writes a failing test that reproduces the bug, then implements the minimal fix, guaranteeing the fix is verified and regression-protected. ## Quick Start Ask the agent to implement a new feature or bug fix using strict test-driven development with tests written and verified failing before any production code.