Moai Library Shadcn

---
name: moai-library-shadcn
description: "Build UI with Core's shadcn/Base UI system. Use for selecting, installing, composing, or customizing shadcn/ui, registry items, themes, and wrappers. Always preserve exact style `base-maia`, Zinc-oriented semantic CSS-variable tokens, and Base UI primitives. Do not use to switch styles, run `shadcn init`, or introduce Radix/React Aria. Pair with `packages/ui/AGENTS.md`."
---

## This repository (Asymmetric-al/core)

These repo-owned sections are intentionally kept on top of the vendored
shadcn skill. If upstream refreshes replace this file, reconcile this overlay
before running `bun run skills:sync`.

### Triggers

- Use for selecting, installing, composing, or customizing shadcn/ui, registry
  items, themes, and wrappers in this repo.
- Use together with `packages/ui/AGENTS.md` and `docs/ai/rules/frontend.md`.
- Do not use to switch styles, run `shadcn init` / `shadcn create`, or introduce
  Radix or React Aria. Never run `shadcn init`. Do not switch Core to
  `base-nova`, `base-luma`, `base-mira`, `base-rhea`, `base-sera`,
  `base-vega`, `base-lyra`, a Radix-based style, or a React Aria-based style.

### Workflow

1. Read `packages/ui/components.json` and confirm `style: "base-maia"`,
   `tailwind.baseColor: "zinc"`, `tailwind.cssVariables: true`.
2. Run `bunx shadcn@latest info --json` from `packages/ui` (never from an app).
3. Search existing `@asym/ui` components before adding anything new.
4. For registry or generated components, inspect CLI output, adapt to Maia, and
   review the full diff. Never `--overwrite` without reviewing customizations.
5. Use Base UI `render` (not Radix `asChild`). Prefer semantic tokens over
   literal `zinc-*` or hardcoded colors.
6. Follow [Core design-system lint](references/design-system-lint.md) for
   scoped lint, raw-finding review, authoring exceptions, and checking consumers
   after shared changes. Preserve other shadcn guardrails and browser evidence
   when visible. Do not load this workflow for unrelated work.

### Checklist

- [ ] Exact `base-maia` / Zinc / CSS variables remain unchanged
- [ ] Shared ownership stays in `packages/ui`
- [ ] Registry output adapted to Core tokens, radii, and primitives
- [ ] No `shadcn init`, preset-switch, Radix, or React Aria
- [ ] Overlay reconciled before `bun run skills:sync`

# shadcn/ui Design System - Skill

**Name:** `moai-library-shadcn`
**Purpose:** Build consistent, accessible UI using shadcn/ui components, tokens, and composable primitives.
Use this skill whenever selecting, installing, composing, or customizing shadcn/ui in this repo.

**Applies when:** Working with shadcn/ui components, Tailwind tokens/themes, registry items, or component wrappers.
**Do not use when:** Switching shadcn styles, running `shadcn init` / `shadcn create`, or introducing Radix / React Aria. Core UI is always Base UI + exact `base-maia`; pair this skill with `packages/ui/AGENTS.md`. Use `base-ui` for primitive API details after this skill.

## Rules

- **Docs first:** Start with [reference-links.md](reference-links.md), then open the exact component doc before editing.
- **Copied-in code is first-party:** Treat `components/ui/*` as owned project code with stable conventions.
- **Prefer install over reinvention:** Use CLI/registry install paths for base components, then customize in wrappers.
- **Behavior primitives stay intact:** Keep accessibility and keyboard behavior from the Base UI-backed internals (this repo is Base UI only).
- **Tokens over one-offs:** Centralize color, radius, spacing, and typography; avoid hardcoded one-off styles.
- **Composable APIs:** Keep props minimal, use Base UI's `render` prop intentionally (no `asChild` here), and avoid boolean-prop explosion.
- **Interoperability guardrail:** If mixing with Base UI primitives, document the boundary and keep one clear owner per interaction.

## Workflow

1. Check whether an existing component already solves the need in `components/ui/*`.
2. Open the relevant docs from [reference-links.md](reference-links.md).
3. Choose install path:
   - CLI/registry install for standard components and blocks.
   - Manual composition only when customization requires it.
4. Compose app-specific wrappers outside `components/ui/*`.
5. Verify keyboard, focus, labels/descriptions, and light/dark behavior.
6. Run scoped quality gates for changed packages.

## Checklists

### Implementation checklist

- [ ] Existing shadcn component evaluated before creating new primitive
- [ ] Token-based styling used (no unnecessary arbitrary values)
- [ ] `cn()` and variants are consistent with existing patterns
- [ ] `render` prop and composition semantics are correct
- [ ] a11y behavior (focus, keyboard, ARIA) preserved

### Review checklist

- [ ] No duplicate component variants that should be shared
- [ ] Wrapper components are outside `components/ui/*`
- [ ] Forms include labels, help text, and error messaging
- [ ] Any Base UI crossover is explicit and justified

## Minimal examples

### Reuse existing primitive

```tsx
import { Button } from "@/components/ui/button";

export function Actions() {
  return (
    <div className="flex gap-2">
      <Button>Save</Button>
      <Button variant="secondary">Cancel</Button>
    </div>
  );
}
```

### Extend in wrapper layer

```tsx
import { Button } from "@/components/ui/button";

type LoadingButtonProps = React.ComponentProps<typeof Button> & {
  loading?: boolean;
};

export function LoadingButton({
  loading,
  children,
  ...props
}: LoadingButtonProps) {
  return (
    <Button disabled={loading} {...props}>
      {children}
    </Button>
  );
}
```

## Additional resources

- Full shadcn docs index: [reference-links.md](reference-links.md)
- Base primitives companion skill: [`docs/ai/skills/base-ui/SKILL.md`](../base-ui/SKILL.md)
- Base docs index: [`docs/ai/skills/base-ui/reference-links.md`](../base-ui/reference-links.md)

## Common mistakes / pitfalls

- Editing copied-in primitives when a thin wrapper is enough
- Ignoring docs updates and relying on stale memory
- Mixing primitive systems inside one component without clear ownership
- Breaking keyboard/focus behavior while styling