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 workflow 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 agent through writing a failing test, verifying the failure, writing minimal passing code, and refactoring while staying green. - Rationalization Detection: Lists common excuses for skipping TDD (sunk cost, manual testing, tests-after) with counterarguments 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 over-mocking, with gate functions to catch violations. - Use Case: When asked to fix a bug where empty emails are accepted, the agent first writes a failing test asserting the rejection error, watches it fail, then implements the minimal validation to make it pass. ## Quick Start Ask the agent to implement a new feature or bugfix using test-driven development with a failing test written first.
