Use when entering a new project for the first time, or when the codebase has changed significantly — generates a yin-side codebase map with structural analysis and silent failure surface assessment
Use when the user describes a small, low-risk change — bug fix with known cause, config change, dependency update, or small refactor under 100 lines
Use when a plan with tasks exists and you need to execute implementation — requires index.yaml and tasks/ directory
Use when implement is complete and feature-level scar items need review — aggregates remaining scars across tasks, triages cross-task patterns, and fixes system-level rot before validate-and-ship
Use when research/kickoff is complete and you need to create an implementation plan with specs, tasks, and acceptance criteria
Use when research output is complete and planning would otherwise need to assume design, task-shape, structural boundaries, or evaluation details before implementation planning
Use when starting new feature work, investigating a problem, or when the user describes something they want to build — before any planning or implementation
Use when all implementation tasks are complete and you need to run validation, review failure budgets, and prepare for shipping — Step 0 is a security & privacy STOP gate that must pass before any other check