Shadcn

It knows the entire component system, handles CLI operations (init, add, search), and enforces the framework's opinionated patterns like using FieldGroup for forms, data-icon for button icons, and gap instead of space-y. It catches common mistakes before they happen: raw divs where Alert should be used, manual dark mode classes instead of semantic tokens, InputGroup composition errors. The skill auto-triggers when it detects a components.json file or preset codes, and it can decode those cryptic preset URLs without you touching the documentation. Think of it as pair programming with someone who has the entire shadcn rule book memorized.