TDD — Test-Driven Development

Overview

Use this skill to drive one concrete behavior into existence through a focused test-first cycle. The cycle is:

BEHAVIOR -> RED -> VERIFY RED -> GREEN -> VERIFY GREEN -> REFACTOR -> VERIFY GREEN

The test is evidence only when it observes the promised behavior at the right boundary and can fail for a meaningful defect. A green test is evidence only when its oracle proves the requirement rather than an implementation shape.

This method is framework-neutral. Identify the repository's test tooling and delegate its commands and mechanics to the applicable project skill.

When to Use