What problem does it solve? Developers often write production code first and add tests afterward, which produces tests that pass immediately and prove nothing about correctness. This Skill enforces a strict test-first discipline so every feature and bugfix is backed by a test that was watched failing before implementation. ## Core Features & Use Cases - Red-Green-Refactor Cycle: Guides the AI through writing a failing test, verifying the failure, writing minimal code to pass, and refactoring while staying green. - Rationalization Detection: Lists common excuses for skipping TDD ("too simple to test", "I'll test after") and counters each with concrete reasoning. - Testing Anti-Patterns Reference: Ships a companion reference covering mock-behavior testing, test-only production methods, incomplete mocks, and over-mocking. - Use Case: When asked to fix a bug where an empty email is accepted, the Skill first writes a failing test reproducing the bug, verifies it fails for the right reason, then implements the minimal validation fix. ## Quick Start Use the test-driven-development skill to implement this feature by writing a failing test first, then the minimal code to make it pass.
