Test-Driven Development

Use this for behavioral changes where a failing test can describe the desired outcome before implementation.

Workflow

1. Understand

• Read the request, Linear ticket, Charter, plan, spec, and relevant code as available.
• Identify the desired behavior, existing contracts, failure paths, and verification.
• If a spec exists, note its invariants, decisions, and testing strategy.
• Ask before writing tests when missing information would materially change behavior, scope, safety, contracts, data shape, or verification.

2. Red

• Write the smallest failing test that proves the desired behavior or reproduces the bug.
• Run it and confirm it fails for the expected reason.

3. Green