Test-Driven Development (TDD)

What I do

• Enforce write-test-first: no production code without a failing test
• Drive the RED → GREEN → REFACTOR cycle with verification at each step
• Keep tests honest (see references/writing-good-tests.md)

When to use me

Always: new features, bug fixes, refactoring, behavior changes.

Exceptions (ask the user): generated code, configuration files, throwaway prototypes. Visual/UI work is not exempt by default — ask the user, and a Playwright or screenshot regression check may substitute for a unit test.

Thinking "skip TDD just this once"? Stop — that is rationalization.

The Iron Law