Turn a concrete product, page, workflow, or feature request into an evidence-backed interaction specification before UI generation begins. Use this skill whenever a user asks to design a new feature, screen, flow, dashboard, form, agent interaction, or substantial redesign and the functional success conditions are not already captured in an approved SPEC.md. Also use it to reconstruct or update a missing feature specification from an existing product. Do not use it for a purely cosmetic change whose behavior and acceptance criteria are already approved.
