Executes plan.md for an active change under Docs/<scope>/Specs/<change-name>/. Use after plan-change when the user approves implementation. Follows tasks in order, validates each step, retries obvious failures once, and stops to ask if blocked. Does not change spec intent without approval.

Turns a change idea into a stable <change-name>_spec.md and actionable plan.md under Docs/<scope>/Specs/<change-name>/. Opens with a fixed prompt for goals/context, then conversationally resolves scope and naming; proceeds through workflow steps in order. Tone: concise, cheerful, inquisitive. Does not create the Specs folder, <change-name>_spec.md, or plan.md until scope and change-name are confirmed. Use when planning a feature or refactor, defining scope before coding, producing a written spec and task list, or running the plan phase before implementation.

Use after implementation when the user approves closeout. Reconcile the active spec and plan with what shipped, propose broader documentation updates for approval, then move the whole change folder from specs/active to specs/completed.