Test-Driven Development Skill

When to Use

• Building new features with clear requirements
• Implementing business logic
• Creating utility functions
• When code needs to be reliable and maintainable

When NOT to Use

• Exploratory prototyping where requirements are unknown and the goal is discovery, not delivery
• Pure configuration changes (environment variables, feature flags, YAML/JSON configs) with no logic
• One-off scripts that will never be maintained or reused
• Trivial getters/setters with no business logic — the test adds no specification value

Instructions

The TDD Cycle