What problem does it solve? Developers often write production code first and add tests afterward, which produces biased 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. - Rationalization Countermeasures: Provides a catalog of common excuses for skipping TDD (sunk cost, manual testing, tests-after) with direct rebuttals and red flags that trigger a restart. - Testing Anti-Pattern Reference: Ships a companion reference covering mock-behavior testing, test-only production methods, incomplete mocks, and mocking without understanding dependencies. - Use Case: When fixing a bug where an empty email is accepted, write a failing test asserting the rejection error, watch it fail, implement the minimal validation, verify green, then refactor. ## Quick Start Use the test-driven-development skill to implement this feature by writing a failing test first and following the red-green-refactor cycle.
