What problem does it solve? Most shipped bugs come from things never written down — missing error states, unverifiable criteria, unstated assumptions. This Skill systematically finds those gaps in plans, acceptance criteria, and design mocks before implementation, then works with you one question at a time to turn each gap into a concrete, testable artifact update. ## Core Features & Use Cases - Checklist-driven gap discovery: Walks dedicated checklists for plans (scope, rollback, observability, security), acceptance criteria (measurability, negative paths, edge cases), and design mocks (loading/empty/error states, content variance, accessibility). - Interactive gap-closing loop: Triages gaps into Blocker / Should-address / Nice-to-have, asks one question at a time, and writes each confirmed answer back into the source artifact as a new AC, plan section, or mock state spec. - Resolution log: Produces a session summary of closed and parked gaps with owners, suitable for PR descriptions or release notes. - Use Case: Before handing a feature spec to engineering, run this Skill to catch that the checkout flow has no payment-decline behavior, no rollback plan for the migration, and no empty state for the contacts list — then capture decisions for each. ## Quick Start Ask the assistant to find gaps in your plan, acceptance criteria, or design mocks and walk through the findings one question at a time.