What problem does it solve? When a verification pass flags gaps in an in-progress task, teams need a disciplined way to close exactly those gaps without scope creep, plan edits, or accidental task completion. This Skill remediates only the named gaps in FIX.md and returns the workstream to the check phase. ## Core Features & Use Cases - Gap-scoped remediation: Reads FIX.md and STATE.json, then closes only the listed gaps through test-first changes, never touching PLAN.md, SPEC.md, or forward tasks. - State-safe transitions: On success it deletes FIX.md and sets phase back to check while keeping the active task in_progress; on failure it halts without writing state. - Self-cleanup enforcement: Audits the task's own git diff against a cleanup checklist to remove debug output, dead code, and orphan files before finishing. - Use Case: After /check flags three failing edge cases in task T-002, invoke this Skill to write failing tests, implement minimal fixes, verify all checks pass, and hand the task back to /check. ## Quick Start Run the fix phase to close the gaps listed in FIX.md for the active task and return the workstream to the check phase.