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 Enforcement: Guides the full TDD cycle with mandatory verification steps, including watching each test fail for the right reason before writing minimal code to pass it. - Rationalization Countermeasures: Provides explicit rebuttals to common excuses like "I'll test after" or "deleting code is wasteful", plus red flags that signal when to delete code and start over. - Testing Anti-Pattern Reference: Ships a companion reference covering mock-behavior testing, test-only production methods, incomplete mocks, and over-mocking, with gate functions to catch violations. - Use Case: When fixing a bug where empty emails are accepted, write a failing test asserting the rejection error, watch it fail, implement the minimal validation, verify all tests pass, then refactor. ## 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.
