shadcn-ui/ui包含需要注意的行為
SKILL DETAIL
shadcn
shadcn-ui/ui/shadcn
shadcn/ui is a framework for building UI, components, and design systems. Components are added as source code to the user's project via the CLI. This skill provides project context, component documentation, and usage examples. It applies when working with shadcn/ui, component registries, presets, --preset codes, or any project with a components.json file. It also triggers for "shadcn init", "create an app with --preset", or "switch to --preset". The skill follows key principles such as using existing components first, composing rather than reinventing, using built-in variants, and using semantic colors. It enforces rules for styling, forms, component structure, icons, and chat interfaces to ensure best practices. CLI commands like npx shadcn@latest manage components, and the skill leverages project context fields (aliases, RSC, Tailwind version, etc.) for accurate guidance.
安裝量 · 1,392查看來源
Installation
npx skills add https://shadcn-ui/ui/
技能檔案
SKILL.md
最近同步 · 2026年10月22日
agents/openai.yml›
interface:
display_name: "shadcn/ui"
short_description: "Manages shadcn/ui components — adding, searching, fixing, debugging, styling, and composing UI."
icon_small: "./assets/shadcn-small.png"
icon_large: "./assets/shadcn.png"
assets/showcase/color-pair.tsx›
import * as React from "react"
import { cn } from "@/lib/utils"
// Resolves any CSS color (hex, rgb, oklch, color-mix) to sRGB by painting one pixel.
// Translucent colors are composited over the backdrop, as the browser would.
function toRgb(color: string, backdrop = "#fff") {
const canvas = document.createElement("canvas")
canvas.width = canvas.height = 1
const context = canvas.getContext("2d", { willReadFrequently: true })
if (!context) {
return null
}
context.fillStyle = backdrop
context.fillRect(0, 0, 1, 1)
context.fillStyle = color
context.fillRect(0, 0, 1, 1)
const [r, g, b] = context.getImageData(0, 0, 1, 1).data
return [r, g, b]
}
function toHex(rgb: number[]) {
return `#${rgb.map((value) => value.toString(16).padStart(2, "0")).join("")}`
}
function luminance([r, g, b]: number[]) {
const [R, G, B] = [r, g, b].map((value) => {
const channel = value / 255
return channel <= 0.03928
? channel / 12.92
: ((channel + 0.055) / 1.055) ** 2.4
})
return 0.2126 * R + 0.7152 * G + 0.0722 * B
}
function contrast(a: number[], b: number[]) {
const [light, dark] = [luminance(a), luminance(b)].sort((x, y) => y - x)
return (light + 0.05) / (dark + 0.05)
}
export function ColorPair({
name,
background,
foreground,
className,
}: {
name: string
background: string
foreground: string
className?: string
}) {
const ref = React.useRef<HTMLDivElement>(null)
const [info, setInfo] = React.useState<{ ratio: number; bg: string } | null>(
null
)
React.useEffect(() => {
const element = ref.current
if (!element) {
return
}
// Re-measure when the theme class on <html> changes.
const measure = () => {
const style = getComputedStyle(element)
const page = getComputedStyle(document.body).backgroundColor
const bg = toRgb(style.backgroundColor, page)
if (!bg) {
return
}
const fg = toRgb(style.color, toHex(bg))
if (fg) {
setInfo({ ratio: contrast(bg, fg), bg: toHex(bg) })
}
}
measure()
const observer = new MutationObserver(measure)
observer.observe(document.documentElement, { attributes: true })
return () => observer.disconnect()
}, [])
const level = !info
? ""
: info.ratio >= 7
? "AAA"
: info.ratio >= 4.5
? "AA"
: info.ratio >= 3
? "AA Large"
: "Fail"
return (
<div
className={cn(
"flex flex-col overflow-hidden rounded-xl border",
className
)}
>
<div
ref={ref}
style={{
backgroundColor: `var(--${background})`,
color: `var(--${foreground})`,
}}
className="flex h-24 items-end justify-between p-4"
>
<span className="text-2xl font-medium">Aa</span>
{info && (
<span className="rounded-full border border-current/20 px-2 py-0.5 font-mono text-xs">
{info.ratio.toFixed(2)} {level}
</span>
)}
</div>
<div className="flex flex-col gap-0.5 bg-background p-3">
<span className="text-sm font-medium">{name}</span>
<span className="font-mono text-xs text-muted-foreground">
--{background} / --{foreground}
</span>
{info && (
<span className="font-mono text-xs text-muted-foreground">
{info.bg}
</span>
)}
</div>
</div>
)
}
assets/showcase/preview-states.css›
/* Add to the app's global CSS after the dark variant. */
/* Lets the design system page pin interaction states with data-preview="hover focus active". */
@custom-variant hover {
@media (hover: hover) {
&:hover {
@slot;
}
}
&[data-preview~="hover"] {
@slot;
}
}
@custom-variant focus-visible (&:focus-visible, &[data-preview~="focus"]);
@custom-variant active (&:active, &[data-preview~="active"]);
assets/showcase/state-matrix.tsx›
import * as React from "react"
import { cn } from "@/lib/utils"
const defaultStates = [
"default",
"hover",
"focus",
"active",
"disabled",
] as const
export function StateMatrix<Row extends string>({
rows,
states = defaultStates,
render,
className,
}: {
rows: readonly Row[]
states?: readonly string[]
render: (row: Row, state: string) => React.ReactNode
className?: string
}) {
return (
<div className={cn("w-full overflow-x-auto", className)}>
<table className="w-full border-separate border-spacing-x-2 border-spacing-y-3">
<thead>
<tr>
<th />
{states.map((state) => (
<th
key={state}
scope="col"
className="text-left font-mono text-xs font-normal text-muted-foreground"
>
{state}
</th>
))}
</tr>
</thead>
<tbody>
{rows.map((row) => (
<tr key={row}>
<th
scope="row"
className="pr-4 text-left font-mono text-xs font-normal text-muted-foreground"
>
{row}
</th>
{states.map((state) => (
<td key={state}>{render(row, state)}</td>
))}
</tr>
))}
</tbody>
</table>
</div>
)
}
// Spread onto a component to pin a state without interaction.
export function previewState(state: string) {
if (state === "disabled") {
return { disabled: true }
}
if (["hover", "focus", "active"].includes(state)) {
return { "data-preview": state }
}
return {}
}
cli.md›
# shadcn CLI Reference
Configuration is read from `components.json`.
> **IMPORTANT:** Always run commands using the project's package runner: `npx shadcn@latest`, `pnpm dlx shadcn@latest`, or `bunx --bun shadcn@latest`. Check `packageManager` from project context to choose the right one. Examples below use `npx shadcn@latest` but substitute the correct runner for the project.
> **IMPORTANT:** Only use the flags documented below. Do not invent or guess flags — if a flag isn't listed here, it doesn't exist. The CLI auto-detects the package manager from the project's lockfile; there is no `--package-manager` flag.
## Contents
- Commands: init, apply, add (dry-run, smart merge), search, view, docs, info, build
- Templates: next, vite, start, react-router, astro
- Presets: named, code, URL formats and fields
- Switching presets
---
## Commands
### `init` — Initialize or create a project
```bash
npx shadcn@latest init [components...] [options]
```
Initializes shadcn/ui in an existing project or creates a new project (when `--name` is provided). Optionally installs components in the same step.
| Flag | Short | Description | Default |
| ----------------------- | ----- | --------------------------------------------------------- | ------- |
| `--template <template>` | `-t` | Template (next, start, vite, next-monorepo, react-router) | — |
| `--preset [name]` | `-p` | Preset configuration (named, code, or URL) | — |
| `--yes` | `-y` | Skip confirmation prompt | `true` |
| `--defaults` | `-d` | Use defaults (`--template=next --preset=base-nova`) | `false` |
| `--force` | `-f` | Force overwrite existing configuration | `false` |
| `--cwd <cwd>` | `-c` | Working directory | current |
| `--name <name>` | `-n` | Name for new project | — |
| `--silent` | `-s` | Mute output | `false` |
| `--rtl` | | Enable RTL support | — |
| `--reinstall` | | Re-install existing UI components | `false` |
| `--monorepo` | | Scaffold a monorepo project | — |
| `--no-monorepo` | | Skip the monorepo prompt | — |
`npx shadcn@latest create` is an alias for `npx shadcn@latest init`.
### `apply` — Apply a preset to an existing project
```bash
npx shadcn@latest apply [preset] [options]
```
Applies a preset to an existing project, overwriting preset-driven config, fonts, CSS variables, and detected UI components.
| Flag | Short | Description | Default |
| ------------------- | ----- | ------------------------------------------ | ------- |
| `--preset <preset>` | — | Preset configuration (named, code, or URL) | — |
| `--yes` | `-y` | Skip confirmation prompt | `false` |
| `--cwd <cwd>` | `-c` | Working directory | current |
| `--silent` | `-s` | Mute output | `false` |
`[preset]` is a shorthand for `--preset <preset>`. If both are provided, they must match.
If no preset is provided, the CLI offers to open the custom preset builder on `ui.shadcn.com/create`.
### `add` — Add components
> **IMPORTANT:** To compare local components against upstream or to preview changes, ALWAYS use `npx shadcn@latest add <component> --dry-run`, `--diff`, or `--view`. NEVER fetch raw files from GitHub or other sources manually. The CLI handles registry resolution, file paths, and CSS diffing automatically.
```bash
npx shadcn@latest add [components...] [options]
```
Accepts component names, registry-prefixed names (`@magicui/shimmer-button`),
GitHub item addresses (`owner/repo/item`), URLs, or local paths.
| Flag | Short | Description | Default |
| --------------- | ----- | -------------------------------------------------------------------------------------------------------------------- | ------- |
| `--yes` | `-y` | Skip confirmation prompt | `false` |
| `--overwrite` | `-o` | Overwrite existing files | `false` |
| `--cwd <cwd>` | `-c` | Working directory | current |
| `--all` | `-a` | Add all available components | `false` |
| `--path <path>` | `-p` | Target path for the component | — |
| `--silent` | `-s` | Mute output | `false` |
| `--dry-run` | | Preview all changes without writing files | `false` |
| `--diff [path]` | | Show diffs. Without a path, shows the first 5 files. With a path, shows that file only (implies `--dry-run`) | — |
| `--view [path]` | | Show file contents. Without a path, shows the first 5 files. With a path, shows that file only (implies `--dry-run`) | — |
#### Dry-Run Mode
Use `--dry-run` to preview what `add` would do without writing any files. `--diff` and `--view` both imply `--dry-run`.
```bash
# Preview all changes.
npx shadcn@latest add button --dry-run
# Show diffs for all files (top 5).
npx shadcn@latest add button --diff
# Show the diff for a specific file.
npx shadcn@latest add button --diff button.tsx
# Show contents for all files (top 5).
npx shadcn@latest add button --view
# Show the full content of a specific file.
npx shadcn@latest add button --view button.tsx
# Works with URLs too.
npx shadcn@latest add https://api.npoint.io/abc123 --dry-run
# Works with public GitHub registries too.
npx shadcn@latest add owner/repo/item --dry-run
# CSS diffs.
npx shadcn@latest add button --diff globals.css
```
**When to use dry-run:**
- When the user asks "what files will this add?" or "what will this change?" — use `--dry-run`.
- Before overwriting existing components — use `--diff` to preview the changes first.
- When the user wants to inspect component source code without installing — use `--view`.
- When checking what CSS changes would be made to `globals.css` — use `--diff globals.css`.
- When the user asks to review or audit third-party registry code before installing — use `--view` to inspect the source.
> **`npx shadcn@latest add --dry-run` vs `npx shadcn@latest view`:** Prefer `npx shadcn@latest add --dry-run/--diff/--view` over `npx shadcn@latest view` when the user wants to preview changes to their project. `npx shadcn@latest view` only shows raw registry metadata. `npx shadcn@latest add --dry-run` shows exactly what would happen in the user's project: resolved file paths, diffs against existing files, and CSS updates. Use `npx shadcn@latest view` only when the user wants to browse registry info without a project context.
#### Smart Merge from Upstream
See [Updating Components in SKILL.md](./SKILL.md#updating-components) for the full workflow.
### `search` — Search registries
```bash
npx shadcn@latest search [registries...] [options]
```
Fuzzy search across registries. Also aliased as `npx shadcn@latest list`.
Supports namespaces (`@acme`), public GitHub registry sources (`owner/repo`),
and registry catalog URLs. Without `-q`, lists all items. When no registries are
passed, searches every registry configured in `components.json`.
| Flag | Short | Description | Default |
| ------------------- | ----- | ------------------------------------------------- | ------- |
| `--query <query>` | `-q` | Search query | — |
| `--type <type>` | `-t` | Filter by item type (e.g. `ui`, `block`, `hook`); comma-separated | — |
| `--limit <number>` | `-l` | Max items to display | `100` |
| `--offset <number>` | `-o` | Items to skip | `0` |
| `--json` | | Output as JSON | `false` |
| `--cwd <cwd>` | `-c` | Working directory | current |
### `view` — View item details
```bash
npx shadcn@latest view <items...> [options]
```
Displays item info including file contents. Examples:
`npx shadcn@latest view @shadcn/button`,
`npx shadcn@latest view owner/repo/item`.
### `docs` — Get component documentation URLs
```bash
npx shadcn@latest docs <components...> [options]
```
Outputs resolved URLs for component documentation, examples, and API references. Accepts one or more component names. Fetch the URLs to get the actual content.
Example output for `npx shadcn@latest docs input button`:
```
base radix
input
docs https://ui.shadcn.com/docs/components/radix/input
examples https://raw.githubusercontent.com/.../examples/input-example.tsx
button
docs https://ui.shadcn.com/docs/components/radix/button
examples https://raw.githubusercontent.com/.../examples/button-example.tsx
```
Some components include an `api` link to the underlying library (e.g. `cmdk` for the command component).
### `diff` — Check for updates
Do not use this command. Use `npx shadcn@latest add --diff` instead.
### `info` — Project information
```bash
npx shadcn@latest info [options]
```
Displays project info and `components.json` configuration. Run this first to discover the project's framework, aliases, Tailwind version, and resolved paths.
| Flag | Short | Description | Default |
| ------------- | ----- | ----------------- | ------- |
| `--cwd <cwd>` | `-c` | Working directory | current |
**Project Info fields:**
| Field | Type | Meaning |
| -------------------- | --------- | ------------------------------------------------------------------ |
| `framework` | `string` | Detected framework (`next`, `vite`, `react-router`, `start`, etc.) |
| `frameworkVersion` | `string` | Framework version (e.g. `15.2.4`) |
| `isSrcDir` | `boolean` | Whether the project uses a `src/` directory |
| `isRSC` | `boolean` | Whether React Server Components are enabled |
| `isTsx` | `boolean` | Whether the project uses TypeScript |
| `tailwindVersion` | `string` | `"v3"` or `"v4"` |
| `tailwindConfigFile` | `string` | Path to the Tailwind config file |
| `tailwindCssFile` | `string` | Path to the global CSS file |
| `aliasPrefix` | `string` | Import alias prefix (e.g. `@`, `~`, `@/`) |
| `packageManager` | `string` | Detected package manager (`npm`, `pnpm`, `yarn`, `bun`) |
**Components.json fields:**
| Field | Type | Meaning |
| -------------------- | --------- | ------------------------------------------------------------------------------------------ |
| `base` | `string` | Primitive library (`radix` or `base`) — determines component APIs and available props |
| `style` | `string` | Visual style (e.g. `nova`, `vega`) |
| `rsc` | `boolean` | RSC flag from config |
| `tsx` | `boolean` | TypeScript flag |
| `tailwind.config` | `string` | Tailwind config path |
| `tailwind.css` | `string` | Global CSS path — this is where custom CSS variables go |
| `iconLibrary` | `string` | Icon library — determines icon import package (e.g. `lucide-react`, `@tabler/icons-react`) |
| `aliases.components` | `string` | Component import alias (e.g. `@/components`) |
| `aliases.utils` | `string` | Utils import alias (e.g. `@/lib/utils`) |
| `aliases.ui` | `string` | UI component alias (e.g. `@/components/ui`) |
| `aliases.lib` | `string` | Lib alias (e.g. `@/lib`) |
| `aliases.hooks` | `string` | Hooks alias (e.g. `@/hooks`) |
| `resolvedPaths` | `object` | Absolute file-system paths for each alias |
| `registries` | `object` | Configured custom registries |
**Links fields:**
The `info` output includes a **Links** section with templated URLs for component docs, source, and examples. For resolved URLs, use `npx shadcn@latest docs <component>` instead.
### `build` — Build a custom registry
```bash
npx shadcn@latest build [registry] [options]
```
Builds `registry.json` into individual JSON files for distribution. Default input: `./registry.json`, default output: `./public/r`.
For authoring rules, `include`, item definitions, `registryDependencies`, and
GitHub registry behavior, see [registry.md](./registry.md).
| Flag | Short | Description | Default |
| ----------------- | ----- | ----------------- | ------------ |
| `--output <path>` | `-o` | Output directory | `./public/r` |
| `--cwd <cwd>` | `-c` | Working directory | current |
---
## Templates
| Value | Framework | Monorepo support |
| -------------- | -------------- | ---------------- |
| `next` | Next.js | Yes |
| `vite` | Vite | Yes |
| `start` | TanStack Start | Yes |
| `react-router` | React Router | Yes |
| `astro` | Astro | Yes |
| `laravel` | Laravel | No |
All templates support monorepo scaffolding via the `--monorepo` flag. When passed, the CLI uses a monorepo-specific template directory (e.g. `next-monorepo`, `vite-monorepo`). When neither `--monorepo` nor `--no-monorepo` is passed, the CLI prompts interactively. Laravel does not support monorepo scaffolding.
---
## Presets
Three ways to specify a preset via `--preset`:
1. **Named:** `--preset nova` or `--preset lyra`
2. **Code:** `--preset a2r6bw` (version-prefixed base62 string, e.g. `a2r6bw` or `b0`)
3. **URL:** `--preset "https://ui.shadcn.com/init?base=radix&style=nova&..."`
> **IMPORTANT:** Never try to decode, fetch, or resolve preset codes manually. Preset codes are opaque — pass them directly to `npx shadcn@latest init --preset <code>` and let the CLI handle resolution.
> Use `npx shadcn@latest apply --preset <code>` when overwriting an existing project's preset.
## Switching Presets
Ask the user first: **overwrite**, **merge**, or **skip** existing components?
- **Overwrite / Re-install** → `npx shadcn@latest apply --preset <code>`. Overwrites all detected component files with the new preset styles. Use when the user hasn't customized components.
- **Merge** → `npx shadcn@latest init --preset <code> --force --no-reinstall`, then run `npx shadcn@latest info` to get the list of installed components and use the [smart merge workflow](./SKILL.md#updating-components) to update them one by one, preserving local changes. Use when the user has customized components.
- **Skip** → `npx shadcn@latest init --preset <code> --force --no-reinstall`. Only updates config and CSS variables, leaves existing components as-is.
Always run preset commands inside the user's project directory. `apply` only works in an existing project with a `components.json` file. The CLI automatically preserves the current base (`base` vs `radix`) from `components.json`. If you must use a scratch/temp directory (e.g. for `--dry-run` comparisons), pass `--base <current-base>` explicitly — preset codes do not encode the base.
customization.md›
# Customization & Theming
Components reference semantic CSS variable tokens. Change the variables to change every component.
## Contents
- How it works (CSS variables → Tailwind utilities → components)
- Color variables and OKLCH format
- Dark mode setup
- Changing the theme (presets, CSS variables)
- Adding custom colors (Tailwind v3 and v4)
- Border radius
- Customizing components (variants, className, wrappers)
- Checking for updates
---
## How It Works
1. CSS variables defined in `:root` (light) and `.dark` (dark mode).
2. Tailwind maps them to utilities: `bg-primary`, `text-muted-foreground`, etc.
3. Components use these utilities — changing a variable changes all components that reference it.
---
## Color Variables
Every color follows the `name` / `name-foreground` convention. The base variable is for backgrounds, `-foreground` is for text/icons on that background.
| Variable | Purpose |
| -------------------------------------------- | -------------------------------- |
| `--background` / `--foreground` | Page background and default text |
| `--card` / `--card-foreground` | Card surfaces |
| `--primary` / `--primary-foreground` | Primary buttons and actions |
| `--secondary` / `--secondary-foreground` | Secondary actions |
| `--muted` / `--muted-foreground` | Muted/disabled states |
| `--accent` / `--accent-foreground` | Hover and accent states |
| `--destructive` / `--destructive-foreground` | Error and destructive actions |
| `--border` | Default border color |
| `--input` | Form input borders |
| `--ring` | Focus ring color |
| `--chart-1` through `--chart-5` | Chart/data visualization |
| `--sidebar-*` | Sidebar-specific colors |
| `--surface` / `--surface-foreground` | Secondary surface |
Colors use OKLCH: `--primary: oklch(0.205 0 0)` where values are lightness (0–1), chroma (0 = gray), and hue (0–360).
---
## Dark Mode
Class-based toggle via `.dark` on the root element. In Next.js, use `next-themes`:
```tsx
import { ThemeProvider } from "next-themes"
<ThemeProvider attribute="class" defaultTheme="system" enableSystem>
{children}
</ThemeProvider>
```
---
## Changing the Theme
```bash
# Apply a preset code from ui.shadcn.com.
npx shadcn@latest apply --preset a2r6bw
# Positional shorthand also works.
npx shadcn@latest apply a2r6bw
# Switch to a named preset and overwrite existing components.
npx shadcn@latest apply --preset nova
# Preserve existing components instead.
npx shadcn@latest init --preset nova --force --no-reinstall
# Use a custom theme URL.
npx shadcn@latest apply --preset "https://ui.shadcn.com/init?base=radix&style=nova&theme=blue&..."
```
Or edit CSS variables directly in `globals.css`.
---
## Adding Custom Colors
Add variables to the file at `tailwindCssFile` from `npx shadcn@latest info` (typically `globals.css`). Never create a new CSS file for this.
```css
/* 1. Define in the global CSS file. */
:root {
--warning: oklch(0.84 0.16 84);
--warning-foreground: oklch(0.28 0.07 46);
}
.dark {
--warning: oklch(0.41 0.11 46);
--warning-foreground: oklch(0.99 0.02 95);
}
```
```css
/* 2a. Register with Tailwind v4 (@theme inline). */
@theme inline {
--color-warning: var(--warning);
--color-warning-foreground: var(--warning-foreground);
}
```
When `tailwindVersion` is `"v3"` (check via `npx shadcn@latest info`), register in `tailwind.config.js` instead:
```js
// 2b. Register with Tailwind v3 (tailwind.config.js).
module.exports = {
theme: {
extend: {
colors: {
warning: "oklch(var(--warning) / <alpha-value>)",
"warning-foreground":
"oklch(var(--warning-foreground) / <alpha-value>)",
},
},
},
}
```
```tsx
// 3. Use in components.
<div className="bg-warning text-warning-foreground">Warning</div>
```
---
## Border Radius
`--radius` controls border radius globally. Components derive values from it (`rounded-lg` = `var(--radius)`, `rounded-md` = `calc(var(--radius) - 2px)`).
When a brand spec defines its own radius scale, pin each step in `@theme inline` (`--radius-sm` … `--radius-4xl`) instead of deriving from `--radius`. See [design-system.md](./design-system.md#radius).
---
## Customizing Components
See also: [rules/styling.md](./rules/styling.md) for Incorrect/Correct examples.
Prefer these approaches in order:
### 1. Built-in variants
```tsx
<Button variant="outline" size="sm">
Click
</Button>
```
### 2. Tailwind classes via `className`
```tsx
<Card className="mx-auto max-w-md">...</Card>
```
### 3. Add a new variant
Edit the component source to add a variant via `cva`:
```tsx
// components/ui/button.tsx
warning: "bg-warning text-warning-foreground hover:bg-warning/90",
```
### 4. Wrapper components
Compose shadcn/ui primitives into higher-level components:
```tsx
export function ConfirmDialog({ title, description, onConfirm, children }) {
return (
<AlertDialog>
<AlertDialogTrigger asChild>{children}</AlertDialogTrigger>
<AlertDialogContent>
<AlertDialogHeader>
<AlertDialogTitle>{title}</AlertDialogTitle>
<AlertDialogDescription>{description}</AlertDialogDescription>
</AlertDialogHeader>
<AlertDialogFooter>
<AlertDialogCancel>Cancel</AlertDialogCancel>
<AlertDialogAction onClick={onConfirm}>Confirm</AlertDialogAction>
</AlertDialogFooter>
</AlertDialogContent>
</AlertDialog>
)
}
```
---
## Checking for Updates
```bash
npx shadcn@latest add button --diff
```
To preview exactly what would change before updating, use `--dry-run` and `--diff`:
```bash
npx shadcn@latest add button --dry-run # see all affected files
npx shadcn@latest add button --diff button.tsx # see the diff for a specific file
```
See [Updating Components in SKILL.md](./SKILL.md#updating-components) for the full smart merge workflow.
design-system-page.md›
# The Design System Page
What goes on a design system page, and how to show it. Distilled from Primer, Carbon, Atlassian, GitLab Pajamas, Cloudscape, Twilio Paste, Salesforce Lightning, Material 3, Evergreen and Orbit, and from EightShapes' component documentation guidance.
## Contents
- Principles
- Page outline
- Foundations
- Components: tiers and block anatomy
- States without interaction
- Edge cases
- Do and Don't
- Recipes and example screens
- Helpers
- Checklist
---
## Principles
1. **Foundations, then components, then compositions.** Every mature system follows this order (Primer, Carbon, Paste, Cloudscape, M3).
2. **Roles, not palettes.** Show each color as a surface paired with its foreground and the measured contrast. The raw palette comes second.
3. **Lead with the typical case.** Each component opens with its most common use in real content. Then come variants in priority order, then shared axes (size, icon), then states.
4. **Pin states so reviewers can see them.** Hover, focus and pressed render side by side without interaction. Use one consistent label, and never put the state name inside the component.
5. **Don't render every combination.** Primitives get a variant × state matrix. Composed components get a typical example plus additions. Exhaustive combinations belong in tests (Material 3 cut its list kit from 700+ variants to about 45).
6. **Real content in the brand's voice.** No lorem ipsum. Include the awkward cases: long text, empty, error, loading.
7. **Composition proves the system.** End with the DESIGN.md's own recipes and one realistic screen built only from the tokens and components.
8. **Make the DESIGN.md's rules visible.** Turn its Do's and Don'ts into rendered do/don't pairs.
---
## Page Outline
| # | Section | Contents |
| --- | -------------------------- | ------------------------------------------------------------------------------------------------------------------------------------ |
| 1 | Header | System name, "Themed from DESIGN.md", section anchors, light/dark toggle, primary CTA. |
| 2 | Overview | The DESIGN.md hero recipe: display type, one-line personality, its signature artifact. |
| 3 | Foundations | Color roles, palette, typography, spacing, radius, elevation, motion (if specified), icons. |
| 4 | Actions | Button, ButtonGroup, Toggle, ToggleGroup, Badge, Kbd. |
| 5 | Inputs | Field, Input, InputGroup, Textarea, Select, NativeSelect, Combobox, Checkbox, RadioGroup, Switch, Slider, InputOTP, Calendar, Label. |
| 6 | Navigation | Tabs, Breadcrumb, Pagination, NavigationMenu, Menubar, Sidebar. |
| 7 | Data display | Card, Table, Chart, Item, Avatar, Accordion, Collapsible, Carousel, ScrollArea, Resizable, AspectRatio, Separator. |
| 8 | Feedback | Alert, toast (and Sonner in Base UI projects), Progress, Spinner, Skeleton, Empty. |
| 9 | Overlays | Dialog, AlertDialog, Sheet, Drawer, Popover, HoverCard, Tooltip, DropdownMenu, ContextMenu, Command. |
| 10 | Conversation | MessageScroller, Message, Bubble, Attachment, Marker, Questionnaire. See [rules/chat.md](./rules/chat.md). |
| 11 | Do and Don't | Rendered pairs for the DESIGN.md's rules. |
| 12 | Recipes and example screen | The DESIGN.md's named components, then one realistic screen. |
| 13 | Footer | The DESIGN.md footer recipe. |
DirectionProvider goes wherever RTL matters (an RTL row in Inputs or Navigation).
Alternate section surfaces the way the DESIGN.md paces its bands. Use `className="dark"` on a section to render a dark band with the same components.
---
## Foundations
### Color roles
A grid of pairs, each rendered as the surface with "Aa" in its foreground color, plus the token names, resolved value and measured contrast (Paste, Material 3, Pajamas):
| Pair | Required |
| ------------------------------------- | ------------ |
| `background` / `foreground` | Yes |
| `card` / `card-foreground` | Yes |
| `popover` / `popover-foreground` | Yes |
| `primary` / `primary-foreground` | Yes |
| `secondary` / `secondary-foreground` | Yes |
| `muted` / `muted-foreground` | Yes |
| `accent` / `accent-foreground` | Yes |
| `destructive` on `background` | Yes |
| Each extra text token on `background` | When defined |
Use `ColorPair` from the helpers. It measures contrast live and re-measures when the theme changes. Report any pair below 4.5:1 for body-size text, even when the DESIGN.md specifies it. A brand primary at 3:1 behind 14px labels is a real finding.
### Palette
Swatches grouped the way the DESIGN.md groups them (brand, surfaces, text, status, accents). Label each with its DESIGN.md name and token, for example "Warm Stone · `surface-warm`". Show `border`, `input`, `ring`, `chart-1…5` and `sidebar-*` here too.
### Typography
A specimen table, one row per type token (Cloudscape, Carbon, Atlassian):
| Column | Content |
| -------- | ------------------------------------------------- |
| Token | `type-display-lg` |
| Spec | size / line height / weight / tracking |
| Use | "Section heads", taken from the DESIGN.md |
| Specimen | Real copy set in the token, truncated to one line |
Group the rows display → title → body → label/caption → code. Below the table, show one paragraph of running text at body size, with a link and inline code, so line length and rhythm are visible.
### Spacing
The base unit and the scale as labeled horizontal bars (Carbon, Atlassian), then a semantic ladder: inside a component, between related items, between groups, between sections (Pajamas). Skip it if the DESIGN.md defines no spacing.
### Radius
The same box at every step, labeled with the token, the value and what uses it (Material 3). Example: `md · 8px · buttons, inputs`.
### Elevation
Each level as a raised surface with the components that rest there (Pajamas, Material 3): flat for canvas and bands, hairline for cards, soft for popovers and menus, deep for dialogs.
### Motion and icons
Show motion only if the DESIGN.md defines durations or easings: a table of token, milliseconds and use. For icons, show one row with the icon library at each size used by components, in `foreground` and `muted-foreground`.
---
## Components: Tiers and Block Anatomy
### Tiers
| Tier | Components | How to show |
| ------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------- |
| Primitives | Button, Badge, Toggle, ToggleGroup, Input, Textarea, Select, NativeSelect, Checkbox, RadioGroup, Switch, Slider, Tabs | Variant × state matrix, size ladder, icon row. |
| Fields | Field, InputGroup, Combobox, InputOTP, Calendar, Label | Typical field, then description, error, disabled, required. |
| Composed | Card, Table, Item, Avatar, Alert, Empty, toast, Sonner, Accordion, Collapsible, Breadcrumb, Pagination, Progress, Skeleton, Spinner, Carousel, Chart, ScrollArea, Resizable, AspectRatio, Separator, Kbd, ButtonGroup | Typical example, then one element added at a time, then edge cases. |
| Overlays | Dialog, AlertDialog, Sheet, Drawer, Popover, HoverCard, Tooltip, DropdownMenu, ContextMenu, Menubar, NavigationMenu, Command | A real trigger per overlay, labeled with what it opens. |
| Shell | Sidebar, DirectionProvider | Inline in a framed preview (`collapsible="none"`). |
| Conversation | MessageScroller, Message, Bubble, Attachment, Marker, Questionnaire | One realistic thread, then variant rows. |
### Block anatomy
Each component block, in this order. Skip the parts that don't apply:
1. **Name and one line on when to use it.** Take the wording from the DESIGN.md recipe when there is one.
2. **Typical example** in real content.
3. **Variants** in priority order (primary before secondary before ghost), each with a one-line "when".
4. **Sizes** as a ladder, smallest to largest.
5. **With icon**: leading, trailing, icon-only.
6. **States**: the matrix for primitives, single examples for the rest.
7. **Edge cases** (see below).
Wide components (Table, NavigationMenu, Menubar, Sidebar, Chart, MessageScroller) span the full row.
---
## States Without Interaction
Pin interaction states with a `data-preview` attribute. Override the hover, focus-visible and active variants so each also matches the attribute. Copy [assets/showcase/preview-states.css](./assets/showcase/preview-states.css) into `tailwindCssFile`:
```css
@custom-variant hover {
@media (hover: hover) {
&:hover {
@slot;
}
}
&[data-preview~="hover"] {
@slot;
}
}
@custom-variant focus-visible (&:focus-visible, &[data-preview~="focus"]);
@custom-variant active (&:active, &[data-preview~="active"]);
```
If the theme adds an unlayered focus rule (for an outline-style focus), add `[data-preview~="focus"]` to its selector too.
Render the matrix with `StateMatrix` and `previewState` from the helpers:
```tsx
const variants = ["default", "secondary", "outline", "ghost", "destructive", "link"] as const
<StateMatrix
rows={variants}
render={(variant, state) => (
<Button variant={variant} {...previewState(state)}>
Save draft
</Button>
)}
/>
```
The columns are default, hover, focus, active and disabled. Add `loading` with Spinner + `disabled` for Button, and `invalid` (`aria-invalid`) for fields:
```tsx
<StateMatrix
rows={["input"] as const}
states={["default", "hover", "focus", "disabled", "invalid"]}
render={(_, state) => (
<Input
placeholder="[email protected]"
aria-invalid={state === "invalid" || undefined}
{...previewState(state)}
/>
)}
/>
```
If the DESIGN.md says a state doesn't change ("primary darkens on press only"), leave that column identical. The matrix shows the spec is followed.
---
## Edge Cases
Show these next to the component they stress:
| Case | Where |
| ------------- | ------------------------------------------------------------------------- |
| Long text | Button label, Badge, Item title, Table cell, Breadcrumb (truncation). |
| Empty | Table with no rows → Empty, Combobox with no matches, empty Command. |
| Error | Field with FieldError, Alert destructive, Attachment `state="error"`. |
| Loading | Button with Spinner, Skeleton for Card and Item, Progress, toast loading. |
| Many items | AvatarGroup with count, Pagination with ellipsis, ScrollArea list. |
| Missing image | Avatar falling back to AvatarFallback. |
| Disabled | Every field and its Field `data-disabled`. |
| RTL | One row inside `DirectionProvider` with `dir="rtl"`. |
---
## Do and Don't
Pick the two to four DESIGN.md rules that are easiest to break and render each as a pair (Primer, Orbit, Carbon):
```tsx
<div className="grid gap-4 md:grid-cols-2">
<Example title="Do">
<Button>Get started</Button>
<Button variant="outline">Contact sales</Button>
</Example>
<Example title="Don't">
<Button>Get started</Button>
<Button>Contact sales</Button>
</Example>
</div>
```
Caption each with the rule in one line, for example "One primary action per group." Mark Don't with `destructive` text, not a new color.
---
## Recipes and Example Screens
**Recipes.** Build each named component in the DESIGN.md (`hero-band`, `feature-card`, `pricing-tier-card`, `callout-card-coral`, `footer`) from shadcn components and tokens. These are the spec's acceptance tests. If a recipe can't be built without raw values, the token mapping is incomplete.
**Example screen.** One realistic screen in the brand's domain (Cloudscape demos, Paste page templates): a settings page (FieldGroup, Switch, Select, Button) or a list view (Table, Badge, Pagination, Empty). Use only tokens and components.
---
## Helpers
Copy from `assets/showcase/` into the showcase folder:
| File | Purpose |
| -------------------- | -------------------------------------------------------------------------- |
| `preview-states.css` | Variant overrides that pin hover, focus and active through `data-preview`. |
| `state-matrix.tsx` | `StateMatrix` (labeled variant × state table) and `previewState(state)`. |
| `color-pair.tsx` | `ColorPair`: surface + foreground with live contrast ratio and WCAG level. |
They import `cn` from `@/lib/utils`. Rewrite that path to the project's `utils` alias.
---
## Checklist
- [ ] Every installed component renders (run the coverage script).
- [ ] Color roles shown as pairs with contrast; any pair under 4.5:1 is noted in the report.
- [ ] Type specimen covers every DESIGN.md type token, in real copy.
- [ ] Radius and elevation ladders name the components that use each step.
- [ ] Primitives have a state matrix; Button and fields include loading and invalid.
- [ ] Edge cases: long text, empty, error, loading, missing image.
- [ ] Do/Don't pairs for the DESIGN.md's key rules.
- [ ] DESIGN.md recipes rebuilt, plus one example screen.
- [ ] Page-level theme toggle works, and at least one scoped dark band if the DESIGN.md has dark surfaces.
- [ ] No lorem ipsum, and no state names inside components.
design-system.md›
# Design Systems from DESIGN.md
Build a new app from a preset, install every component, restyle it from a `DESIGN.md`, then render a design system page.
Trigger phrases: "build me a design system using <preset>", "apply this DESIGN.md", "create a showcase / design system page", "make shadcn look like <brand>".
## Contents
- Inputs to confirm
- Step 1: Scaffold
- Step 2: Install everything
- Step 3: Read the DESIGN.md
- Step 4: Map tokens to the theme
- Step 5: Map component recipes to variants
- Step 6: Build the design system page ([design-system-page.md](./design-system-page.md))
- Step 7: Verify
- Report back
---
## Inputs to Confirm
| Input | Default | Notes |
| --------- | ----------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------- |
| Preset | Optional | Code (`b0`), style name (`luma`) or URL. Pass it through. Never decode it by hand. Without one, pick a style (see Step 1). |
| DESIGN.md | Required | A path, URL or pasted content. Copy it into the new app root as `DESIGN.md`. |
| Template | `vite` | Use `next` when the user says Next.js, App Router or SSR. |
| App name | Derived from the brand in DESIGN.md | Kebab-case. |
| Base | `base` | Pass `--base` when no preset code is given. Use `radix` only when the user asks. `info --json` after init decides `render` vs `asChild`. |
If the DESIGN.md path can't be read (macOS privacy blocks `~/Downloads` and `~/Desktop` for some hosts), ask the user to copy it into the working directory. Don't guess its contents.
---
## Step 1: Scaffold
With a preset code from the user:
```bash
npx shadcn@latest init --preset <code> --template vite --name <app> --no-monorepo -y
```
Without one, pick the style whose geometry is closest to the DESIGN.md and pass it with `--base`:
```bash
npx shadcn@latest init --base base --preset <style> --template vite --name <app> --no-monorepo -y
```
Then:
```bash
cd <app>
npx shadcn@latest info --json
```
`init` with neither `--preset` nor `--base` stops at an interactive library prompt, even with `-y`. Always pass one of them, plus `--no-monorepo`.
### Picking a style
The theme gets replaced by the DESIGN.md anyway. The style decides geometry the CSS variables can't reach: control padding, density, how rounded and how raised the components are. Read the DESIGN.md's radius scale, control heights, shadows and layout density, then pick:
| Style | Character | Pick when the DESIGN.md has |
| ------ | ----------------------------------------------------- | ---------------------------------------------------------------------- |
| `vega` | The classic shadcn/ui look. | Neutral, conventional SaaS geometry; nothing extreme. |
| `nova` | Reduced padding and margins for compact layouts. | 32–36px controls, 6–8px radius, hairlines over shadows. |
| `maia` | Soft and rounded, with generous spacing. | 40px+ controls, 12px+ card radius, generous padding, editorial pacing. |
| `lyra` | Boxy and sharp. | 0–4px radius, hard edges, mono or technical type. |
| `mira` | Compact. | Dense data UIs, 28–32px controls, tight tables. |
| `luma` | Rounded geometry, soft elevation, breathable layouts. | Pill buttons, soft layered shadows, glassy or macOS-like surfaces. |
| `rhea` | Luma, but more compact. | Luma's softness with product-UI density. |
| `sera` | Editorial and typographic. | Serif display type, editorial pacing, magazine-like hierarchy. |
State the choice and the reason in one line ("Picked maia: 40px controls, 12–16px cards, generous padding"). If the user names a style, use it. Read `base`, `style`, `iconLibrary`, `tailwindCssFile` and `aliases` from `info` before writing any code.
## Step 2: Install Everything
```bash
npx shadcn@latest add --all -y
ls <resolvedPaths.ui>/*.tsx | wc -l
```
Count the component files on disk. Never quote a component count from memory.
Then wire up the providers in the app root:
- Wrap the app in `TooltipProvider`.
- Base UI: wrap the app in `Toaster` from the `toast` component and call `toast.add({ title, description, type })`. Radix: render `<Toaster />` from `sonner`.
Then typecheck the app sources. In Vite apps, the root `tsc --noEmit` checks nothing because the root tsconfig only has project references:
```bash
npx tsc -p tsconfig.app.json --noEmit # Vite.
npx tsc --noEmit # Next.js.
```
Fix generated files that fail strict checks (for example, an unused `React` import) before moving on, or `vite build` will fail.
---
## Step 3: Read the DESIGN.md
DESIGN.md files usually carry YAML frontmatter (`colors`, `typography`, `rounded`, `spacing`, `components`) and prose sections (Overview, Colors, Typography, Layout, Elevation, Shapes, Components, Do's and Don'ts, Responsive, Known Gaps). Some only have prose with `{colors.x}` references. Handle both.
Long files exceed one read. Grep the headings first, then read frontmatter, **Do's and Don'ts**, **Iteration Guide** and **Known Gaps** in full. Those sections hold the rules that override defaults.
Extract into a working table before editing anything:
| Extract | Look for |
| --------------------- | --------------------------------------------------------------------- |
| Canvas and ink | `canvas`, `surface`, `ink`, "page floor", "body text" |
| Action color + states | `primary`, `-hover`, `-active`, `-pressed`, `-disabled`, `on-primary` |
| Secondary actions | `button-secondary` fill, text and border |
| Surfaces | card fills, soft bands, dark product surfaces |
| Lines | `hairline`, border alpha, "1px solid" |
| Focus | outline vs ring, color, width, offset, alpha |
| Type families | display, body, mono, and the documented **substitutes** |
| Type scale | size, weight, line height, tracking per token |
| Radius scale | every value and what it applies to |
| Elevation | each shadow tier, verbatim |
| Control heights | button, input, ghost, icon-button heights and padding |
| Hard rules | every "Don't" and "never" |
---
## Step 4: Map Tokens to the Theme
Edit only `tailwindCssFile`. Keep hex values when the DESIGN.md gives hex. Don't convert them to OKLCH.
### Role mapping
| DESIGN.md role | shadcn variable |
| -------------------------------------------- | ----------------------------------------------------------- |
| canvas / surface / page floor | `--background` |
| ink / headline text | `--foreground`, `--card-foreground`, `--popover-foreground` |
| primary CTA fill / on-primary | `--primary` / `--primary-foreground` |
| primary hover, pressed or active fill | new `--primary-active` (or `--primary-pressed`) |
| secondary button fill / text | `--secondary` / `--secondary-foreground` |
| soft band, alternating section | `--muted` |
| secondary or descriptive text | `--muted-foreground` |
| ghost hover wash, active tab, menu highlight | `--accent` / `--accent-foreground` |
| card / feature card fill | `--card` |
| floating layer (menus, dialogs) | `--popover` (usually the canvas) |
| hairline / structural border | `--border`, `--input` |
| focus color | `--ring` |
| error / validation | `--destructive` |
| illustration accents | `--chart-1` … `--chart-5`, plus named tokens |
| sidebar or nav rail surface | `--sidebar-*` |
Every token without a shadcn slot gets a variable in `:root` (and `.dark` when it changes) and a registration in `@theme inline`:
```css
:root {
--primary-active: #a9583e;
--surface-card: #efe9de;
}
@theme inline {
--color-primary-active: var(--primary-active);
--color-surface-card: var(--surface-card);
}
```
### Radius
A DESIGN.md radius scale rarely fits the `--radius` multipliers. Pin each step in `@theme inline` instead. These are the classes base-nova components use:
| Class | Used by |
| ------------- | ----------------------------------------------- |
| `rounded-sm` | Small accents |
| `rounded-md` | Menu, select and command items |
| `rounded-lg` | Buttons, inputs, selects, tabs, popovers, menus |
| `rounded-xl` | Cards, dialogs, command |
| `rounded-2xl` | Toasts, large containers |
| `rounded-4xl` | Badges (pill) |
```css
@theme inline {
/* DESIGN.md step → Tailwind class used by that component. */
--radius-sm: 4px; /* xs: accents. */
--radius-md: 6px; /* sm: menu items. */
--radius-lg: 8px; /* md: buttons, inputs. */
--radius-xl: 12px; /* lg: cards, dialogs. */
--radius-2xl: 16px; /* xl: toasts, hero containers. */
--radius-3xl: 16px;
--radius-4xl: 9999px; /* pill: badges. */
}
```
Replace the existing `--radius-*` lines in `@theme inline` rather than adding a second block. Confirm the classes for the installed style:
```bash
grep -ohE "rounded-(\[[^ \"]+\]|[a-z0-9]+)" <ui>/*.tsx | sort | uniq -c
```
`rounded-[min(var(--radius-md),Npx)]` caps small buttons and select triggers. Edit the cap when the DESIGN.md wants rounder small controls.
### Elevation
Override Tailwind's shadow scale in `@theme`, not `@theme inline`. Copy multi-layer shadows verbatim. Set `--shadow-xs` to `0 0 #0000` when the system is hairline-only, because inputs and outline buttons use it.
```css
@theme {
--shadow-xs: 0 0 #0000;
--shadow-sm: 0 1px 3px rgb(20 20 19 / 0.08);
--shadow-lg: 0 1px 3px rgb(20 20 19 / 0.08), 0 8px 24px rgb(20 20 19 / 0.06);
}
```
### Fonts
Brand fonts are usually licensed. Use the substitutes the DESIGN.md names, installed from Fontsource with the project's package manager, and import every face you reference at the top of the CSS file:
```bash
npm install @fontsource-variable/inter @fontsource-variable/cormorant-garamond @fontsource-variable/jetbrains-mono
```
```css
@import "@fontsource-variable/inter";
@import "@fontsource-variable/cormorant-garamond";
@import "@fontsource-variable/jetbrains-mono";
@theme inline {
--font-sans: "Inter Variable", -apple-system, system-ui, sans-serif;
--font-serif: "Cormorant Garamond Variable", Garamond, serif;
--font-mono: "JetBrains Mono Variable", ui-monospace, monospace;
--font-heading: var(--font-sans);
}
```
`--font-heading` styles small component titles (`CardTitle`, `DialogTitle`, `SheetTitle`). Point it at the display face only when that face reads well at 16px. Otherwise keep it on the sans and use display tokens for page headings.
### Type scale
Turn every typography token into a `type-*` utility. Don't use `--text-*` theme keys for this, because `cn()` treats unknown `text-*` classes as colors and drops whichever comes first when one sits next to `text-muted-foreground`.
```css
@utility type-display-lg {
font-family: var(--font-serif);
font-size: clamp(34px, 3vw + 16px, 48px);
font-weight: 500;
line-height: 1.1;
letter-spacing: -0.021em;
}
@utility type-caption-upper {
font-size: 12px;
font-weight: 500;
letter-spacing: 1.5px;
text-transform: uppercase;
}
```
- Clamp display sizes so mobile works. Convert pixel tracking to `em` (`-1px / 48px = -0.021em`) so the ratio holds as the size shrinks.
- Respect the rules on tracking (none below a size) and weight (display never bold).
### Dark mode
- **DESIGN.md defines dark surfaces** (product mockups, footers): put them in `.dark`. Because shadcn's `@custom-variant dark (&:is(.dark *))` scopes to descendants, `className="dark"` on any section renders every component inside it with dark tokens. Use it for dark bands, featured pricing cards and footers.
- **DESIGN.md is light-only**: derive `.dark` from the brand's known dark surfaces and tell the user it's derived.
### Focus
Match the documented focus treatment:
- **Ring with alpha** (for example "3px coral at 15%"): replace `ring-ring/50` with the documented alpha on field components (`input`, `textarea`, `input-group`, `select`, `native-select`, `combobox`, `input-otp`).
- **Solid outline with offset**: add an unlayered rule so it beats `outline-none`, and cancel the ring shadow:
```css
:is(
button,
a[href],
[role="button"],
[role="tab"],
[role="checkbox"],
[role="radio"],
[role="switch"],
[role="slider"]
):focus-visible {
outline: 2px solid var(--ring);
outline-offset: 2px;
--tw-ring-shadow: 0 0 #0000;
}
```
This covers actions only. Field controls keep their ring. When the DESIGN.md applies the outline to fields too, add `input, textarea, select, [role="combobox"]` to the selector.
---
## Step 5: Map Component Recipes to Variants
Restyle by editing the `cva` variants in the installed component source. Keep existing variant names so usage stays standard. Add a variant only when the DESIGN.md defines a distinct recipe.
| DESIGN.md recipe | shadcn target |
| ------------------------------------ | -------------------------------------------- |
| `button-primary` | `Button` `default` |
| `button-secondary` (tinted fill) | `Button` `secondary` |
| `button-secondary` (canvas + border) | `Button` `outline` |
| `button-ghost`, nav links | `Button` `ghost` |
| text link | `Button` `link` |
| circular icon button | `Button` `icon*` sizes + `rounded-full` |
| `badge-pill`, `badge-<accent>` | `Badge` `secondary`, `default`, new variants |
| `card`, `feature-card` | `Card` (fill, ring, `--card-spacing`) |
| `text-input`, `-focused` | `Input`, `InputGroup`, `Select`, `Textarea` |
| `category-tab`, filter row | `Tabs` `default` list + trigger |
**Control heights move together.** When the button height changes, change the field controls to match, or forms misalign. In base-nova the 32px default lives in:
| File | Class |
| ------------------- | -------------------------------- |
| `button.tsx` | `h-8`, `size-8` (icon) |
| `input.tsx` | `h-8` |
| `input-group.tsx` | `h-8` |
| `select.tsx` | `data-[size=default]:h-8` |
| `native-select.tsx` | `h-8` |
| `combobox.tsx` | `min-h-8` (chips) |
| `toggle.tsx` | `h-8 min-w-8` |
| `input-otp.tsx` | `size-8` (slot) |
| `tabs.tsx` | `group-data-horizontal/tabs:h-8` |
| `menubar.tsx` | `h-8` |
| `command.tsx` | `h-8!` (input group) |
Re-grep before editing (`grep -n "\bh-8\b\|size-8\b" <ui>/*.tsx`); other styles use different values.
**States.** Follow the documented states exactly. If the DESIGN.md says "darken on press only", use `active:` instead of `hover:`. Keep hover on ghost buttons and menu items even when the spec omits it, and tell the user you did.
**Hard rules.** Turn each "Don't" into a check before you finish, for example: no radius outside the scale, no accent color on buttons, no bold display type.
---
## Step 6: Build the Design System Page
Follow [design-system-page.md](./design-system-page.md). It sets the section outline, how to present each foundation, the component tiers and block anatomy, pinned state matrices, edge cases, do/don't pairs, and recipes.
In short:
1. Foundations first: color roles as contrast-checked pairs, palette, type specimen table, spacing, radius and elevation ladders.
2. Components by tier: primitives get a variant × state matrix, size ladder and icon row. Composed components get a typical example, additions and edge cases. Overlays get real triggers.
3. Then rendered do/don't pairs for the DESIGN.md's rules, the DESIGN.md's named recipes rebuilt from components, and one example screen.
Copy the helpers from `assets/showcase/` (`preview-states.css`, `state-matrix.tsx`, `color-pair.tsx`). Put sections in `src/showcase/<section>.tsx` (Vite) or `app/design-system/` (Next.js). Write copy in the brand's voice.
### Known traps
| Component | Trap | Fix |
| ------------------- | --------------------------------------------------------------------------- | --------------------------------------------------------------------------- |
| `Command` inline | cmdk scrolls its first item into view on mount, which jumps the page to it. | Control it: `value={value} onValueChange={setValue}` with initial `"none"`. |
| `Sidebar` | Default sidebar is `fixed` and escapes the preview frame. | `<SidebarProvider className="min-h-0">` + `<Sidebar collapsible="none">`. |
| `MessageFooter` | Placed beside `MessageContent`, it becomes a squeezed flex column. | Put it inside `MessageContent`. |
| `Select` (base) | `SelectValue` shows the raw value. | Pass `items` to `Select`. |
| `Resizable` | react-resizable-panels v4 dropped `direction` and numeric sizes. | `orientation="horizontal"`, `defaultSize="40%"`. |
| `DirectionProvider` | Provider alone doesn't flip layout. | Also set `dir="rtl"` on the wrapper. |
| `NavigationMenu` | The content is clipped by the example frame. | Leave bottom padding in that frame. |
| Header nav links | `Button` renders a `<button>`. | Base: `nativeButton={false} render={<a href="#…" />}`. Radix: `asChild`. |
### Coverage check
```bash
node <skill-dir>/scripts/showcase-coverage.mjs src/components/ui src # Vite.
node <skill-dir>/scripts/showcase-coverage.mjs components/ui app # Next.js.
```
It lists every component file that no showcase file imports. Fix the list until it's empty. `add --all` installs both `toast` and `sonner` in Base UI projects; show `sonner` in Feedback next to `toast` so the list can reach zero.
---
## Step 7: Verify
Start the dev server and check it in a browser:
1. App typecheck passes (see Step 2).
2. No console errors.
3. Loads at `scrollY === 0`. Anything else means a component is stealing scroll on mount.
4. No horizontal overflow at 375px and 1280px: `document.documentElement.scrollWidth <= innerWidth`.
5. Screenshot the hero, Foundations, one form section and one dark band. Compare against the DESIGN.md: canvas color, CTA color, display font, radius, focus ring.
6. Toggle dark mode once.
---
## Report Back
- App path, dev URL, component count from disk.
- The style picked (when no preset was given) and why.
- What maps where: colors, fonts (and substitutes), radius, shadows, focus.
- Contrast pairs under 4.5:1, including ones the DESIGN.md itself specifies.
- Every component file you edited and why.
- Every deliberate deviation from the DESIGN.md (derived dark mode, kept hover, substituted fonts).
evals/evals.json›
{
"skill_name": "shadcn",
"evals": [
{
"id": 1,
"prompt": "I'm building a Next.js app with shadcn/ui (base-nova preset, lucide icons). Create a settings form component with fields for: full name, email address, and notification preferences (email, SMS, push notifications as toggle options). Add validation states for required fields.",
"expected_output": "A React component using FieldGroup, Field, ToggleGroup, data-invalid/aria-invalid validation, gap-* spacing, and semantic colors.",
"files": [],
"expectations": [
"Uses FieldGroup and Field components for form layout instead of raw div with space-y",
"Uses Switch for independent on/off notification toggles (not looping Button with manual active state)",
"Uses data-invalid on Field and aria-invalid on the input control for validation states",
"Uses gap-* (e.g. gap-4, gap-6) instead of space-y-* or space-x-* for spacing",
"Uses semantic color tokens (e.g. bg-background, text-muted-foreground, text-destructive) instead of raw colors like bg-red-500",
"No manual dark: color overrides"
]
},
{
"id": 2,
"prompt": "Create a dialog component for editing a user profile. It should have the user's avatar at the top, input fields for name and bio, and Save/Cancel buttons with appropriate icons. Using shadcn/ui with radix-nova preset and tabler icons.",
"expected_output": "A React component with DialogTitle, Avatar+AvatarFallback, data-icon on icon buttons, no icon sizing classes, tabler icon imports.",
"files": [],
"expectations": [
"Includes DialogTitle for accessibility (visible or with sr-only class)",
"Avatar component includes AvatarFallback",
"Icons on buttons use the data-icon attribute (data-icon=\"inline-start\" or data-icon=\"inline-end\")",
"No sizing classes on icons inside components (no size-4, w-4, h-4, etc.)",
"Uses tabler icons (@tabler/icons-react) instead of lucide-react",
"Uses asChild for custom triggers (radix preset)"
]
},
{
"id": 3,
"prompt": "Create a dashboard component that shows 4 stat cards in a grid. Each card has a title, large number, percentage change badge, and a loading skeleton state. Using shadcn/ui with base-nova preset and lucide icons.",
"expected_output": "A React component with full Card composition, Skeleton for loading, Badge for changes, semantic colors, gap-* spacing.",
"files": [],
"expectations": [
"Uses full Card composition with CardHeader, CardTitle, CardContent (not dumping everything into CardContent)",
"Uses Skeleton component for loading placeholders instead of custom animate-pulse divs",
"Uses Badge component for percentage change instead of custom styled spans",
"Uses semantic color tokens instead of raw color values like bg-green-500 or text-red-600",
"Uses gap-* instead of space-y-* or space-x-* for spacing",
"Uses size-* when width and height are equal instead of separate w-* h-*"
]
},
{
"id": 4,
"prompt": "I'm building a Next.js app with shadcn/ui (base-nova preset, lucide icons). Build a chat conversation view: a scrollable thread of messages from two different people, each with an avatar, sender name, timestamp, and message bubble. A couple of messages include an image attachment and a PDF file attachment, and there's a 'Today' divider separating the days.",
"expected_output": "A React component composing MessageScroller, Message, Bubble, Attachment, and Marker from the registry instead of hand-rolled bubble/divider/attachment markup.",
"files": [],
"expectations": [
"Uses MessageScroller (MessageScrollerProvider, MessageScrollerViewport, MessageScrollerContent, MessageScrollerItem) for the scrollable thread instead of a raw overflow-y-auto div or ScrollArea",
"Wraps each row in MessageScrollerItem inside MessageScrollerContent",
"Uses Message with MessageAvatar/MessageContent/MessageHeader for row layout instead of custom flex divs",
"Uses Bubble + BubbleContent for the message surface instead of a styled div with bg-muted/bg-primary",
"Uses Attachment (AttachmentMedia, AttachmentContent, AttachmentTitle, AttachmentDescription) for the file and image attachments instead of Item or a custom card",
"Uses Marker (variant=\"separator\") for the 'Today' divider instead of Separator plus a centered label",
"Uses semantic color tokens and gap-* spacing; no raw colors like bg-emerald-500 and no space-y-*",
"Includes \"use client\" when the component uses state or event handlers (isRSC)"
]
},
{
"id": 5,
"prompt": "Using shadcn/ui (base-nova preset, lucide icons), build a streaming AI chat UI. The assistant's reply streams in while it generates, the view auto-scrolls to follow the latest content but stops following if the user scrolls up to read earlier messages, a 'jump to latest' button appears when the user has scrolled away from the bottom, and a subtle 'thinking…' shimmer shows while the model is generating.",
"expected_output": "A React component that delegates scroll/anchor behavior to MessageScroller and uses MessageScrollerButton for jump-to-latest and the shimmer utility for the thinking indicator — no hand-rolled scroll logic or custom shimmer keyframes.",
"files": [],
"expectations": [
"Uses MessageScroller with MessageScrollerProvider (autoScroll) and scrollAnchor on message items for the stick-to-bottom/follow behavior instead of a custom useStickToBottom hook or ResizeObserver/scrollTop wiring",
"Uses MessageScrollerButton for the jump-to-latest control instead of a hand-built conditional button driven by manual scroll-position state",
"Uses the shimmer utility class for the 'thinking…' indicator instead of a custom @keyframes or bg-clip-text gradient animation",
"Wraps each message row in MessageScrollerItem inside MessageScrollerContent",
"Uses Message + Bubble + BubbleContent for the conversation rows instead of hand-rolled bubble divs",
"Uses semantic color tokens and gap-* spacing; includes \"use client\" (isRSC)"
]
},
{
"id": 6,
"prompt": "Build me a design system using preset b0. Use the DESIGN.md in this folder (a productivity-app spec: white canvas, #0075DE primary, 8px buttons, 12px cards, multi-layer soft shadows, 2px blue focus outline with 2px offset).",
"expected_output": "A new Vite app created with init --preset b0 --template vite, every component installed, a design system page that renders all of them, and the DESIGN.md tokens mapped onto the shadcn theme.",
"files": [],
"expectations": [
"Creates the app with init --preset b0 --template vite --name <app> and passes the preset code through without decoding it",
"Installs every component with add --all and reports the component count from disk",
"Reads the DESIGN.md Do's and Don'ts and Known Gaps before editing the theme",
"Maps DESIGN.md colors onto shadcn variables in the existing tailwindCssFile and registers extra tokens in @theme inline instead of creating a new CSS file",
"Pins the radius scale in @theme inline and overrides the shadow scale with the documented multi-layer shadows",
"Implements the 2px outline focus with an offset instead of keeping the default ring",
"Changes field control heights together with the button height",
"Renders every installed component on the design system page and runs the coverage check",
"Verifies in a browser: typecheck, no console errors, page loads at the top, no horizontal overflow",
"Shows color roles as surface/foreground pairs with measured contrast ratios",
"Shows a variant × state matrix for Button with hover, focus, active and disabled pinned via data-preview",
"Renders do/don't pairs for rules from the DESIGN.md"
]
},
{
"id": 7,
"prompt": "Create a Next.js design system app called editorial from preset b0 and apply this DESIGN.md: cream canvas #faf9f5, coral primary #cc785c that darkens only on press, licensed serif display (substitute Cormorant Garamond), Inter body, dark #181715 product surfaces, 40px buttons and inputs.",
"expected_output": "A Next.js app with all components, serif display type utilities, coral primary with an active-only darker state, dark bands scoped with the dark class, and a showcase page covering every component.",
"files": [],
"expectations": [
"Uses --template next with --preset b0 and --name editorial",
"Installs the documented font substitutes from Fontsource instead of linking licensed fonts",
"Defines type-* utilities for the display scale with serif family, weight 400-500 and negative tracking, instead of --text-* theme keys",
"Uses active: rather than hover: for the primary darker state, per the DESIGN.md",
"Raises button and input heights to 40px across button, input, input-group, select and related controls",
"Uses className=\"dark\" on sections or cards to render dark product surfaces with the same components",
"Avoids the cmdk mount scroll jump on the inline Command example",
"Reports deliberate deviations from the DESIGN.md (font substitutes, kept hover, derived values)"
]
},
{
"id": 8,
"prompt": "Create a new design system using shadcn and the following DESIGN.md. <DESIGN.md: editorial cream canvas, coral primary, 40px controls, 12px cards, 16px hero container, pill badges, shadows rare, generous 32px card padding>",
"expected_output": "A new app scaffolded without a preset code by picking a style that matches the DESIGN.md geometry, then themed, with a full design system page.",
"files": [],
"expectations": [
"Does not ask for or invent a preset code; passes --base base --preset <style> so init doesn't stop at an interactive prompt",
"Picks a style matching the DESIGN.md geometry (e.g. maia for generous spacing and 12px+ cards, or sera for editorial serif type) and states the reason in one line",
"Passes --no-monorepo and --template vite (or next when asked)",
"Installs all components and builds the design system page per design-system-page.md",
"Reports contrast pairs below 4.5:1, including the DESIGN.md's own primary/on-primary pair if it fails"
]
}
]
}
mcp.md›
# shadcn MCP Server
The CLI includes an MCP server that lets AI assistants search, browse, view, and install items from registries.
---
## Setup
```bash
shadcn mcp # start the MCP server (stdio)
shadcn mcp init # write config for your editor
```
Editor config files:
| Editor | Config file |
| ----------- | ------------------------------- |
| Claude Code | `.mcp.json` |
| Cursor | `.cursor/mcp.json` |
| VS Code | `.vscode/mcp.json` |
| OpenCode | `opencode.json` |
| Codex | `~/.codex/config.toml` (manual) |
---
## Tools
> **Tip:** MCP tools handle registry operations (search, view, install). For project configuration (aliases, framework, Tailwind version), use `npx shadcn@latest info` — there is no MCP equivalent.
### `shadcn:get_project_registries`
Returns registry names from `components.json`. Errors if no `components.json` exists.
**Input:** none
### `shadcn:list_items_in_registries`
Lists all items from one or more registries. Registries can be configured
namespaces such as `@acme`, public GitHub sources such as `owner/repo`, or
registry catalog URLs. Omit `registries` to list from every registry configured
in `components.json`.
**Input:** `registries` (string[], optional — omit for all configured), `types` (string[], optional — e.g. `["ui", "block"]`), `limit` (number, optional, defaults to 100), `offset` (number, optional)
### `shadcn:search_items_in_registries`
Fuzzy search across registries. Registries can be configured namespaces, public
GitHub sources, or registry catalog URLs. Omit `registries` to search every
registry configured in `components.json` — e.g. "find me a hero" across all
configured registries.
**Input:** `registries` (string[], optional — omit for all configured), `query` (string), `types` (string[], optional — e.g. `["ui", "block"]`), `limit` (number, optional, defaults to 100), `offset` (number, optional)
### `shadcn:view_items_in_registries`
View item details including full file contents.
**Input:** `items` (string[]) — e.g.
`["@shadcn/button", "@shadcn/card", "owner/repo/item"]`
### `shadcn:get_item_examples_from_registries`
Find usage examples and demos with source code. Omit `registries` to search
every registry configured in `components.json`.
**Input:** `registries` (string[], optional — omit for all configured), `query` (string) — e.g. `"accordion-demo"`, `"button example"`
### `shadcn:get_add_command_for_items`
Returns the CLI install command.
**Input:** `items` (string[]) — e.g. `["@shadcn/button"]`
### `shadcn:get_audit_checklist`
Returns a checklist for verifying components (imports, deps, lint, TypeScript).
**Input:** none
---
## Configuring Registries
Namespaced and authenticated registries are set in `components.json`. The
`@shadcn` registry is always built-in. Public GitHub registries can also be used
directly as `owner/repo` registry sources when the repository has a root
`registry.json`; they do not need `components.json` configuration.
```json
{
"registries": {
"@acme": "https://acme.com/r/{name}.json",
"@private": {
"url": "https://private.com/r/{name}.json",
"headers": { "Authorization": "Bearer ${MY_TOKEN}" }
}
}
}
```
- Names must start with `@`.
- URLs must contain `{name}`.
- `${VAR}` references are resolved from environment variables.
Community registry index: `https://ui.shadcn.com/r/registries.json`
registry.md›
# Registry Authoring and Addresses
Use this reference when the user wants to create, fix, publish, or reason about
a shadcn registry.
## Mental Model
A registry has two forms:
- **Source registry**: an authored `registry.json` in a project or repository.
It may use `include` and file paths that point at source files.
- **Built registry**: generated JSON files served to CLI consumers, usually
from `public/r`. Use `npx shadcn@latest build` to create this form.
The CLI installer consumes registry item payloads. A source registry is a way to
author those payloads from real files.
Registry items are not limited to React components. They can distribute
components, hooks, utilities, design tokens, pages, config files, docs, rules,
workflows, templates, MCP files, and other project files.
## Root `registry.json`
The root registry file should define registry metadata and either `items` or
`include`.
```json
{
"$schema": "https://ui.shadcn.com/schema/registry.json",
"name": "acme",
"homepage": "https://acme.com",
"items": [
{
"name": "absolute-url",
"type": "registry:lib",
"title": "Absolute URL",
"description": "A utility to turn any path into an absolute URL.",
"files": [
{
"path": "lib/absolute-url.ts",
"type": "registry:lib"
}
]
}
]
}
```
Root registry rules:
- Root `registry.json` must include `name` and `homepage`.
- `items` is an array of registry item definitions.
- `include` may be used to split the source registry into multiple files.
- Included registry files may omit `name` and `homepage`.
## Include
Use `include` to keep large registries modular.
```json
{
"$schema": "https://ui.shadcn.com/schema/registry.json",
"name": "acme",
"homepage": "https://acme.com",
"include": ["registry/ui/registry.json", "registry/blocks/registry.json"]
}
```
Include rules:
- Include paths are relative to the `registry.json` that declares them.
- Include paths must explicitly point to a `registry.json` file.
- Do not use remote URLs, absolute paths, or parent traversal (`..`).
- Item file paths are relative to the registry file that declares the item.
- Duplicate item names fail across the resolved registry.
Example included file:
```json
{
"items": [
{
"name": "button",
"type": "registry:ui",
"files": [
{
"path": "button.tsx",
"type": "registry:ui"
}
]
}
]
}
```
If this file is at `registry/ui/registry.json`, then `button.tsx` is read from
`registry/ui/button.tsx`, and the built item path is emitted relative to the
root registry.
## Item Definitions
Common item fields:
```json
{
"name": "login-form",
"type": "registry:block",
"title": "Login Form",
"description": "A login form with email and password fields.",
"dependencies": ["zod"],
"registryDependencies": ["button", "input", "label"],
"files": [
{
"path": "blocks/login-form.tsx",
"type": "registry:block"
}
],
"cssVars": {
"light": {
"brand": "oklch(0.62 0.18 250)"
},
"dark": {
"brand": "oklch(0.72 0.16 250)"
}
}
}
```
Important fields:
- `name`: the installable item name. It is not necessarily a file path.
- `type`: one of the registry item types, such as `registry:ui`,
`registry:block`, `registry:lib`, `registry:hook`, `registry:file`,
`registry:page`, `registry:theme`, `registry:style`, `registry:font`, or
`registry:item`.
- `files`: source files copied or generated by the item.
- `dependencies`: npm runtime dependencies.
- `devDependencies`: npm development dependencies.
- `registryDependencies`: other registry items required by this item.
- `cssVars`, `css`, `tailwind`, `envVars`, and `docs`: optional install-time
additions.
File rules:
- File paths are relative to the declaring `registry.json`.
- `registry:file` and `registry:page` files require a `target`.
- Do not use remote file URLs in source registry file paths.
- Keep source files copy-pasteable: no hidden app-only imports.
## Registry Dependencies
`registryDependencies` entries are item addresses, not file paths.
```json
{
"name": "login-form",
"type": "registry:block",
"registryDependencies": ["button", "@acme/input", "acme/ui/card#v1.2.0"],
"files": [
{
"path": "blocks/login-form.tsx",
"type": "registry:block"
}
]
}
```
Dependency rules:
- Bare names such as `"button"` mean official shadcn items.
- Bare names never mean same-registry or same-repository items.
- Namespaced dependencies use `@namespace/item-name`.
- GitHub dependencies use `owner/repo/item-name`.
- Pin GitHub dependencies with `owner/repo/item-name#ref` when needed.
- Refs are not inherited. If `owner/repo/foo#v2` depends on `bar` from the same
repo at `v2`, write `owner/repo/bar#v2`.
- Do not use relative dependencies such as `"./bar"`.
## Address Schemes
When reasoning about a registry item string, classify it first.
| Address | Scheme | Meaning |
| ----------------------------------- | --------- | ------------------------------------------------------------ |
| `button` | shadcn | Official shadcn item named `button`. |
| `@acme/button` | namespace | Item `button` from configured registry `@acme`. |
| `@acme/ui/button` | namespace | Item `ui/button` from configured registry `@acme`. |
| `https://example.com/r/button.json` | url | Built registry item JSON at that URL. |
| `./button.json` | file | Built registry item JSON on disk. |
| `acme/ui/button` | github | Item `button` from GitHub repo `acme/ui`. |
| `acme/ui/forms/login#main` | github | Item `forms/login` from GitHub repo `acme/ui` at ref `main`. |
For namespace and GitHub addresses, slashful item names are allowed and are item
names, not file paths. Addresses ending in `.json` keep file-address
precedence, so `acme/ui/data/schema.json` is treated as a file path, not a
GitHub item address.
## GitHub Registries
A public GitHub repository can act as a source registry when it has a root
`registry.json`.
```txt
owner/repo/item-name[#ref]
```
Rules:
- The first two path segments are GitHub owner and repo.
- All remaining path segments are the registry item name.
- The source entrypoint is always root `registry.json`.
- GitHub registries are source registries consumed directly by the CLI. They do
not require `shadcn build` or generated item JSON files.
- `include` follows the same source-registry rules as local registries.
- Currently, GitHub addresses support public `github.com` repositories only.
- Private repos and GitHub Enterprise require explicit product decisions.
When implementing GitHub registry fetching, resolve refs to a commit SHA before
reading source files. Do not read moving refs directly from
`raw.githubusercontent.com`, because branch-like refs can be cached for several
minutes.
Preferred flow:
```txt
owner/repo[#ref]
-> resolve ref with git ls-remote
-> commit SHA
-> read https://raw.githubusercontent.com/{owner}/{repo}/{sha}/registry.json
-> read includes and item files from the same SHA
```
This keeps a command on one consistent repository snapshot.
Full 40-character commit SHAs are already stable and can be used directly.
Branches, tags, and short refs require Git so the CLI can resolve them to a
commit SHA first.
## Build and Verify
Use the CLI to build source registries:
```bash
npx shadcn@latest build
npx shadcn@latest build registry.json --output public/r
```
Use CLI commands to inspect the result:
```bash
npx shadcn@latest list @acme
npx shadcn@latest search @acme -q "login"
npx shadcn@latest view @acme/login-form
npx shadcn@latest add @acme/login-form --dry-run
npx shadcn@latest registry validate ./registry.json
```
Use GitHub addresses directly for public GitHub registries:
```bash
npx shadcn@latest list owner/repo
npx shadcn@latest search owner/repo -q "login"
npx shadcn@latest view owner/repo/item
npx shadcn@latest add owner/repo/item --dry-run
npx shadcn@latest registry validate owner/repo
```
When working on registry implementation in the shadcn/ui codebase:
- Keep address parsing pure and testable.
- Do not add side effects to validators.
- Preserve existing behavior for official shadcn, namespace, URL, and file
schemes.
- Add tests for address parsing, source loading, dependency resolution, list,
search, view, and add paths.
- Prefer small source-reader abstractions over a plugin system until there are
multiple real providers.
rules/base-vs-radix.md›
# Base vs Radix
API differences between `base` and `radix`. Check the `base` field from `npx shadcn@latest info`.
## Contents
- Composition: asChild vs render
- Button / trigger as non-button element
- Select (items prop, placeholder, positioning, multiple, object values)
- ToggleGroup (type vs multiple)
- Slider (scalar vs array)
- Accordion (type and defaultValue)
---
## Composition: asChild (radix) vs render (base)
Radix uses `asChild` to replace the default element. Base uses `render`. Don't wrap triggers in extra elements.
**Incorrect:**
```tsx
<DialogTrigger>
<div>
<Button>Open</Button>
</div>
</DialogTrigger>
```
**Correct (radix):**
```tsx
<DialogTrigger asChild>
<Button>Open</Button>
</DialogTrigger>
```
**Correct (base):**
```tsx
<DialogTrigger render={<Button />}>Open</DialogTrigger>
```
This applies to all trigger and close components: `DialogTrigger`, `SheetTrigger`, `AlertDialogTrigger`, `DropdownMenuTrigger`, `PopoverTrigger`, `TooltipTrigger`, `CollapsibleTrigger`, `DialogClose`, `SheetClose`, `NavigationMenuLink`, `BreadcrumbLink`, `SidebarMenuButton`, `Badge`, `Item`.
---
## Button / trigger as non-button element (base only)
When `render` changes an element to a non-button (`<a>`, `<span>`), add `nativeButton={false}`.
**Incorrect (base):** missing `nativeButton={false}`.
```tsx
<Button render={<a href="/docs" />}>Read the docs</Button>
```
**Correct (base):**
```tsx
<Button render={<a href="/docs" />} nativeButton={false}>
Read the docs
</Button>
```
**Correct (radix):**
```tsx
<Button asChild>
<a href="/docs">Read the docs</a>
</Button>
```
Same for triggers whose `render` is not a `Button`:
```tsx
// base.
<PopoverTrigger render={<InputGroupAddon />} nativeButton={false}>
Pick date
</PopoverTrigger>
```
---
## Select
**items prop (base only).** Base requires an `items` prop on the root. Radix uses inline JSX only.
**Incorrect (base):**
```tsx
<Select>
<SelectTrigger><SelectValue placeholder="Select a fruit" /></SelectTrigger>
</Select>
```
**Correct (base):**
```tsx
const items = [
{ label: "Select a fruit", value: null },
{ label: "Apple", value: "apple" },
{ label: "Banana", value: "banana" },
]
<Select items={items}>
<SelectTrigger>
<SelectValue />
</SelectTrigger>
<SelectContent>
<SelectGroup>
{items.map((item) => (
<SelectItem key={item.value} value={item.value}>{item.label}</SelectItem>
))}
</SelectGroup>
</SelectContent>
</Select>
```
**Correct (radix):**
```tsx
<Select>
<SelectTrigger>
<SelectValue placeholder="Select a fruit" />
</SelectTrigger>
<SelectContent>
<SelectGroup>
<SelectItem value="apple">Apple</SelectItem>
<SelectItem value="banana">Banana</SelectItem>
</SelectGroup>
</SelectContent>
</Select>
```
**Placeholder.** Base uses a `{ value: null }` item in the items array. Radix uses `<SelectValue placeholder="...">`.
**Content positioning.** Base uses `alignItemWithTrigger`. Radix uses `position`.
```tsx
// base.
<SelectContent alignItemWithTrigger={false} side="bottom">
// radix.
<SelectContent position="popper">
```
---
## Select — multiple selection and object values (base only)
Base supports `multiple`, render-function children on `SelectValue`, and object values with `itemToStringValue`. Radix is single-select with string values only.
**Correct (base — multiple selection):**
```tsx
<Select items={items} multiple defaultValue={[]}>
<SelectTrigger>
<SelectValue>
{(value: string[]) => value.length === 0 ? "Select fruits" : `${value.length} selected`}
</SelectValue>
</SelectTrigger>
...
</Select>
```
**Correct (base — object values):**
```tsx
<Select defaultValue={plans[0]} itemToStringValue={(plan) => plan.name}>
<SelectTrigger>
<SelectValue>{(value) => value.name}</SelectValue>
</SelectTrigger>
...
</Select>
```
---
## ToggleGroup
Base uses a `multiple` boolean prop. Radix uses `type="single"` or `type="multiple"`.
**Incorrect (base):**
```tsx
<ToggleGroup type="single" defaultValue="daily">
<ToggleGroupItem value="daily">Daily</ToggleGroupItem>
</ToggleGroup>
```
**Correct (base):**
```tsx
// Single (no prop needed), defaultValue is always an array.
<ToggleGroup defaultValue={["daily"]} spacing={2}>
<ToggleGroupItem value="daily">Daily</ToggleGroupItem>
<ToggleGroupItem value="weekly">Weekly</ToggleGroupItem>
</ToggleGroup>
// Multi-selection.
<ToggleGroup multiple>
<ToggleGroupItem value="bold">Bold</ToggleGroupItem>
<ToggleGroupItem value="italic">Italic</ToggleGroupItem>
</ToggleGroup>
```
**Correct (radix):**
```tsx
// Single, defaultValue is a string.
<ToggleGroup type="single" defaultValue="daily" spacing={2}>
<ToggleGroupItem value="daily">Daily</ToggleGroupItem>
<ToggleGroupItem value="weekly">Weekly</ToggleGroupItem>
</ToggleGroup>
// Multi-selection.
<ToggleGroup type="multiple">
<ToggleGroupItem value="bold">Bold</ToggleGroupItem>
<ToggleGroupItem value="italic">Italic</ToggleGroupItem>
</ToggleGroup>
```
**Controlled single value:**
```tsx
// base — wrap/unwrap arrays.
const [value, setValue] = React.useState("normal")
<ToggleGroup value={[value]} onValueChange={(v) => setValue(v[0])}>
// radix — plain string.
const [value, setValue] = React.useState("normal")
<ToggleGroup type="single" value={value} onValueChange={setValue}>
```
---
## Slider
Base accepts a plain number for a single thumb. Radix always requires an array.
**Incorrect (base):**
```tsx
<Slider defaultValue={[50]} max={100} step={1} />
```
**Correct (base):**
```tsx
<Slider defaultValue={50} max={100} step={1} />
```
**Correct (radix):**
```tsx
<Slider defaultValue={[50]} max={100} step={1} />
```
Both use arrays for range sliders. Controlled `onValueChange` in base may need a cast:
```tsx
// base.
const [value, setValue] = React.useState([0.3, 0.7])
<Slider value={value} onValueChange={(v) => setValue(v as number[])} />
// radix.
const [value, setValue] = React.useState([0.3, 0.7])
<Slider value={value} onValueChange={setValue} />
```
---
## Accordion
Radix requires `type="single"` or `type="multiple"` and supports `collapsible`. `defaultValue` is a string. Base uses no `type` prop, uses `multiple` boolean, and `defaultValue` is always an array.
**Incorrect (base):**
```tsx
<Accordion type="single" collapsible defaultValue="item-1">
<AccordionItem value="item-1">...</AccordionItem>
</Accordion>
```
**Correct (base):**
```tsx
<Accordion defaultValue={["item-1"]}>
<AccordionItem value="item-1">...</AccordionItem>
</Accordion>
// Multi-select.
<Accordion multiple defaultValue={["item-1", "item-2"]}>
<AccordionItem value="item-1">...</AccordionItem>
<AccordionItem value="item-2">...</AccordionItem>
</Accordion>
```
**Correct (radix):**
```tsx
<Accordion type="single" collapsible defaultValue="item-1">
<AccordionItem value="item-1">...</AccordionItem>
</Accordion>
```
rules/chat.md›
# Chat & Messaging
Components for conversation and chat UI. Compose these instead of hand-rolling
bubbles, scroll containers, dividers, or attachment cards.
Install: `npx shadcn@latest add message-scroller message bubble attachment marker trace code-block`
The same component names and props ship for both `base` and `radix`; only
composition differs (`render` vs `asChild`). See [base-vs-radix.md](./base-vs-radix.md).
## Contents
- Scrollable threads use MessageScroller
- Message rows use Message
- Message surfaces use Bubble
- Attachments use Attachment
- System notes and dividers use Marker
- Assistant activity uses Trace
- Code and tool output use CodeBlock
- Streaming, anchoring, and jump-to-latest are built in
- Escape hatch: the scroller hooks
---
## Scrollable threads use MessageScroller
A conversation that scrolls, follows new messages, restores position, or jumps
to a message uses `MessageScroller`. Don't build a raw overflow container with
manual scroll wiring, and don't reach for `ScrollArea`.
The parts nest in a fixed order. Every direct child of the content is wrapped in
a `MessageScrollerItem` so the scroller can measure, anchor, preserve position,
track visibility, and jump to it. `MessageScrollerButton` sits inside
`MessageScroller`, after the viewport.
**Incorrect:**
```tsx
// Hand-rolled scroll container with manual stick-to-bottom logic.
<div ref={scrollRef} onScroll={handleScroll} className="flex-1 overflow-y-auto">
<div className="flex flex-col gap-6 p-4">
{messages.map((m) => (
<ChatMessage key={m.id} message={m} />
))}
</div>
</div>
```
**Correct:**
```tsx
<MessageScrollerProvider autoScroll>
<MessageScroller>
<MessageScrollerViewport>
<MessageScrollerContent>
{messages.map((message) => (
<MessageScrollerItem
key={message.id}
messageId={message.id}
scrollAnchor={message.role === "user"}
>
<Message align={message.role === "user" ? "end" : "start"}>
{/* ...message content... */}
</Message>
</MessageScrollerItem>
))}
</MessageScrollerContent>
</MessageScrollerViewport>
<MessageScrollerButton />
</MessageScroller>
</MessageScrollerProvider>
```
---
## Message rows use Message
`Message` lays out a single row: avatar, header, content, footer, with
alignment. Group consecutive rows from one sender with `MessageGroup`. Don't
rebuild the row from flex divs.
`align="end"` is the current user's side; `align="start"` is everyone else.
```tsx
<Message align="start">
<MessageAvatar>
<Avatar>
<AvatarImage src={sender.avatar} alt={sender.name} />
<AvatarFallback>{initials}</AvatarFallback>
</Avatar>
</MessageAvatar>
<MessageContent>
<MessageHeader>{sender.name}</MessageHeader>
<Bubble>
<BubbleContent>{text}</BubbleContent>
</Bubble>
<MessageFooter>{time}</MessageFooter>
</MessageContent>
</Message>
```
---
## Message surfaces use Bubble
The colored message surface is `Bubble` + `BubbleContent`, never a styled `div`
with `bg-muted` / `bg-primary` and hand-managed corners.
- `variant`: `default`, `secondary`, `muted`, `tinted`, `outline`, `ghost`, `destructive`.
- `align`: `start` or `end` (matches the `Message` side).
`BubbleReactions` renders the reaction cluster. `side` (`top` | `bottom`) and
`align` (`start` | `end`) position it against the bubble. Don't lay reactions out
with absolutely-positioned `Badge`s.
**Incorrect:**
```tsx
<div className="w-fit rounded-2xl bg-primary px-3 py-2 text-primary-foreground">
{text}
</div>
```
**Correct:**
```tsx
<Bubble variant="default" align="end">
<BubbleContent>{text}</BubbleContent>
<BubbleReactions side="bottom" align="end">
<Badge variant="secondary">👍 2</Badge>
</BubbleReactions>
</Bubble>
```
---
## Attachments use Attachment
File and image attachments use `Attachment`, not `Item` or a custom card. It
carries upload state, so wire `state` to the real status rather than rendering a
separate spinner.
- `state`: `idle`, `uploading`, `processing`, `error`, `done`. `uploading` and
`processing` apply the `shimmer` animation to the title automatically.
- `size`: `default`, `sm`, `xs`. `orientation`: `horizontal`, `vertical`.
- Use `AttachmentGroup` to lay out several attachments in a scrolling row.
```tsx
<Attachment state="done">
<AttachmentMedia variant="icon">
<FileTextIcon />
</AttachmentMedia>
<AttachmentContent>
<AttachmentTitle>homepage-feedback.pdf</AttachmentTitle>
<AttachmentDescription>PDF · 2.4 MB</AttachmentDescription>
</AttachmentContent>
<AttachmentActions>
<AttachmentAction>
<DownloadIcon />
</AttachmentAction>
</AttachmentActions>
</Attachment>
```
For an image, use `<AttachmentMedia variant="image">` with an `img` child.
---
## System notes and dividers use Marker
Status lines ("Sarah joined the conversation"), date dividers ("Today"), and
labeled separators are `Marker`, not a `Separator` plus a centered span.
- `variant`: `default` (plain row), `separator` (centered label with rules on
each side), `border` (bottom-bordered row).
- `MarkerIcon` holds a leading icon; `MarkerContent` holds the label.
**Incorrect:**
```tsx
<div className="flex items-center gap-3 py-2">
<Separator className="flex-1" />
<span className="text-xs text-muted-foreground">Today</span>
<Separator className="flex-1" />
</div>
```
**Correct:**
```tsx
<Marker variant="separator">
<MarkerContent>Today</MarkerContent>
</Marker>
```
---
## Assistant activity uses Trace
What the assistant did or is doing (reasoning, tool calls, chain of thought,
steps, sources, file reads) is a `TraceLine` in a `Trace`, not a hand-rolled
`Collapsible` or a `Marker`. One line reports one thing; it may have detail.
- `TraceLine` is always the line: a `TraceIcon` and a `TraceTitle`, then an
optional `TraceDescription` for a count, a duration or a diff stat. `status`
goes on the `TraceLine`. Never hand-roll a span for secondary text.
- Behavior wraps the line. To make a line do something, wrap it in that thing's
trigger:
- nothing to open: the `TraceLine` alone;
- expands: `TraceCollapsible` > `TraceCollapsibleTrigger` > `TraceLine`, then
`TraceCollapsibleContent`. The trigger adds its own chevron;
- link: `<a href>` > `TraceLine`;
- overlay: `<SheetTrigger>` > `TraceLine` (Dialog, Drawer and Popover the
same). Aria: `<DialogTrigger><Button>` > `TraceLine`, with React Aria's
`Button`.
- Never make the line the trigger: no `asChild` or `render={<TraceLine />}` on
a trigger. The trigger must stay a real button.
- A `TraceCollapsibleTrigger` always has a `TraceCollapsibleContent`. A tool row
is a `TraceLine` until its output arrives, then a `TraceCollapsible`.
- Rows rendered from message parts go in one `Trace` per run of parts. A text
part or a pending approval ends the run. A heading for a run is plain text
above it, or a collapsible summary row.
- A pending approval (`approval-requested`) is a prompt, not a row. Render it
outside `Trace` as an `Item` with Approve and Deny in `ItemActions`. See
/docs/ai-elements/base/confirmation. Once answered, the tool part is a line
again.
- A summary (sources, a task, a whole turn) is a `TraceCollapsible` whose
`TraceCollapsibleContent` holds a `Trace`. Set the parent line's status and
title from its children yourself.
- `status` is `"running"`, `"error"` or `"pending"` (a plan step that has not
started), or omitted. The words agree: Running, Ran, Failed to run. Never dim
a line with `opacity-*`. Map SDK states yourself; never pass one through.
- Add a trailing `TraceIcon` only for a link (arrow-up-right for a new tab, with
sr-only " (opens in a new tab)" in the `TraceTitle`) or an overlay
(chevron-right).
- Open state goes on `TraceCollapsible`: `defaultOpen`, or `open` with
`onOpenChange` (aria: `defaultExpanded`, or `isExpanded` with
`onExpandedChange`).
- Use `Marker` for notes and dividers between turns, not for activity.
- A checkpoint marks a turn the reader can return to. Render a `Marker`
separator after that message, with a Button that calls `setMessages` with the
messages up to and including it. See /docs/ai-elements/base/checkpoint.
- A folder of files is nested `Collapsible`s, one folder per row, and a file is
a `Button`. See /docs/ai-elements/base/file-tree. A single file the assistant
read is still a `TraceLine`.
- A person's turn is a `Message` with `align="end"` and a `Bubble`. The
assistant's answer is a `Message`. See /docs/ai-elements/base/message.
- A thread is those turns in `MessageScroller`. The person's turn is the
`scrollAnchor`, and `autoScroll` follows the reply. See
/docs/ai-elements/base/chat.
- A prompt is an `InputGroup`: a textarea, an attachment chip, and a submit
button. See /docs/ai-elements/base/prompt-input.
- A suggestion is a `Button` that sends its label with `sendMessage({ text })`.
See /docs/ai-elements/base/suggestion.
- A model picker is a `DropdownMenu` with a `DropdownMenuRadioGroup`, next to a
second one for effort. Send the selected ids on `sendMessage` as
`body.model` and `body.effort`. See /docs/ai-elements/base/model-selector.
- An inline citation is a `HoverCard` on a short `Button` in the sentence, from
a `source-url` part. See /docs/ai-elements/base/inline-citation. A list of
sources after the answer is still Sources.
- Context usage is a `HoverCard` with `Progress`, read from message metadata
`usage`. The window size is the model's limit. See
/docs/ai-elements/base/context.
- Asked for an AI Elements component such as Tool, Reasoning, Chain of Thought,
Task, Plan, Sources or Subagent? It is a component page built with Trace (for example
/docs/ai-elements/base/tool). Install `trace` and copy the composition.
Message is one turn (/docs/ai-elements/base/message). Chat is the thread in
Message Scroller (/docs/ai-elements/base/chat). Checkpoint is a Marker
(/docs/ai-elements/base/checkpoint). File Tree is nested
Collapsibles (/docs/ai-elements/base/file-tree). Confirmation is an Item
(/docs/ai-elements/base/confirmation). Prompt Input is an Input Group
(/docs/ai-elements/base/prompt-input). Suggestion is a Button
(/docs/ai-elements/base/suggestion). Model Selector is a Dropdown Menu
(/docs/ai-elements/base/model-selector). Inline Citation is a Hover Card
(/docs/ai-elements/base/inline-citation). Context is a Hover Card and Progress
(/docs/ai-elements/base/context).
**Incorrect:**
```tsx
const [open, setOpen] = useState(true)
<Collapsible open={open} onOpenChange={setOpen}>
<CollapsibleTrigger className="text-sm text-muted-foreground">
{isStreaming ? "Thinking..." : "Thought for a few seconds"}
</CollapsibleTrigger>
<CollapsibleContent>{part.text}</CollapsibleContent>
</Collapsible>
```
**Correct:**
```tsx
<TraceCollapsible>
<TraceCollapsibleTrigger>
<TraceLine status={running ? "running" : undefined}>
<TraceIcon>
<BrainIcon />
</TraceIcon>
<TraceTitle>{running ? "Thinking" : "Thought"}</TraceTitle>
</TraceLine>
</TraceCollapsibleTrigger>
<TraceCollapsibleContent>{part.text}</TraceCollapsibleContent>
</TraceCollapsible>
```
**Incorrect:** a tool row whose output may not exist yet.
```tsx
<TraceCollapsible>
<TraceCollapsibleTrigger>
<TraceLine status={status}>…</TraceLine>
</TraceCollapsibleTrigger>
{output && <TraceCollapsibleContent>{output}</TraceCollapsibleContent>}
</TraceCollapsible>
```
**Correct:** a `TraceLine` until there is something to open.
```tsx
function ToolRow({
icon,
title,
status,
output,
}: {
icon: React.ReactNode
title: string
status?: "running" | "error"
output?: string
}) {
const line = (
<TraceLine status={status}>
<TraceIcon>{icon}</TraceIcon>
<TraceTitle>{title}</TraceTitle>
</TraceLine>
)
if (output === undefined) {
return line
}
return (
<TraceCollapsible>
<TraceCollapsibleTrigger>{line}</TraceCollapsibleTrigger>
<TraceCollapsibleContent>
<CodeBlock size="sm">
<CodeBlockContent wrap className="max-h-64">
{output}
</CodeBlockContent>
</CodeBlock>
</TraceCollapsibleContent>
</TraceCollapsible>
)
}
```
**Incorrect:** the trigger renders as the line, so it is a span.
```tsx
<Sheet>
<SheetTrigger asChild>
<TraceLine>…</TraceLine>
</SheetTrigger>
</Sheet>
```
**Correct:** sources, each link wrapping its own line.
```tsx
<TraceCollapsible>
<TraceCollapsibleTrigger>
<TraceLine>
<TraceIcon>
<GlobeIcon />
</TraceIcon>
<TraceTitle>Used {sources.length} sources</TraceTitle>
</TraceLine>
</TraceCollapsibleTrigger>
<TraceCollapsibleContent>
<Trace>
{sources.map((source) => (
<a key={source.url} href={source.url} target="_blank" rel="noreferrer">
<TraceLine>
<TraceIcon>
<GlobeIcon />
</TraceIcon>
<TraceTitle>
{source.title}
<span className="sr-only"> (opens in a new tab)</span>
</TraceTitle>
<TraceIcon>
<ArrowUpRightIcon />
</TraceIcon>
</TraceLine>
</a>
))}
</Trace>
</TraceCollapsibleContent>
</TraceCollapsible>
```
---
## Code and tool output use CodeBlock
Code, terminal output, tool input and output, logs, stack traces and diffs are
a `CodeBlock`, never a hand-rolled `<pre>`.
- `CodeBlockContent` takes a string. Add `wrap` for tool output and errors,
`lineNumbers` for source, and a `max-h-*` class to cap the height.
- Errors use `variant="destructive"` on `CodeBlock`. Don't recolor the block.
- For diffs and highlighted lines, map each line to a `CodeBlockLine` with
`variant="added"`, `"removed"` or `"highlighted"`.
- `CodeBlockCopyButton` takes the text to copy as `value`.
- Output inside a Trace row is `size="sm"` with `wrap` and `max-h-64`, so long
output wraps and scrolls inside the row. Docs, Markdown fences and chat
answers use the default size.
- Header buttons go in `CodeBlockActions`. With no header, put
`CodeBlockActions` directly in `CodeBlock`; it floats and shows on hover.
- `code-block` installs `use-highlighted-code`. For source code, map the lines
of `useHighlightedCode(code, language)` into `CodeBlockLine`. In a Server
Component, use `await highlightCode(code, language)` instead. Don't
highlight tool output; pass the string.
- `startLine` numbers a snippet from the middle of a file.
**Incorrect:**
```tsx
<pre className="rounded-md bg-muted p-3 font-mono text-xs whitespace-pre-wrap">
{output}
</pre>
```
**Correct:**
```tsx
<CodeBlock>
<CodeBlockHeader>
<CodeBlockTitle>Output</CodeBlockTitle>
<CodeBlockActions>
<CodeBlockCopyButton value={output} />
</CodeBlockActions>
</CodeBlockHeader>
<CodeBlockContent wrap className="max-h-72">
{output}
</CodeBlockContent>
</CodeBlock>
```
---
## Streaming, anchoring, and jump-to-latest are built in
`MessageScroller` handles the behavior that chat UIs usually reinvent. Don't
write a `useStickToBottom` hook, a `ResizeObserver`, or manual `scrollTop` math.
- **Follow the live edge while streaming.** `MessageScrollerProvider` with
`autoScroll` keeps the view pinned to new content and yields the moment the
user scrolls up. Streaming token updates that grow the last message are
followed automatically.
- **Anchor a turn.** `scrollAnchor` on a `MessageScrollerItem` marks the row to
hold in view (typically the user's message that started the turn).
- **Jump to latest.** `MessageScrollerButton` appears when the user scrolls away
and scrolls back on click. `direction="end"` (default) or `direction="start"`.
It is a self-managing control, so don't gate it behind your own scroll-position
state.
- **Open a saved transcript without a flash.** `defaultScrollPosition` applies
after mount. When it is `"end"` or `"last-anchor"`, the viewport has
`data-pending-scroll` until that position is applied. The styled viewport
hides. For `"end"` on first paint when messages are in the server HTML, copy
this script into the page, not into the primitive. Skip it for `"last-anchor"`
and for client-fetched messages. Keep `suppressHydrationWarning` on the
viewport. Pass a `nonce` if you use a Content Security Policy.
```tsx
const scrollToEndScript = `(function () {
var viewport = document.getElementById("messages")
if (!viewport) {
return
}
viewport.scrollTop = viewport.scrollHeight
viewport.removeAttribute("data-pending-scroll")
})()`
<MessageScroller>
<MessageScrollerViewport id="messages" suppressHydrationWarning>
<MessageScrollerContent>{/* transcript */}</MessageScrollerContent>
</MessageScrollerViewport>
<script dangerouslySetInnerHTML={{ __html: scrollToEndScript }} />
<MessageScrollerButton />
</MessageScroller>
```
For a "thinking…" indicator while the model generates, apply the `shimmer`
utility to text. Don't author a custom keyframe animation. See
[styling.md](./styling.md).
---
## Escape hatch: the scroller hooks
For behavior the parts don't expose, read state from the hooks rather than
re-implementing the scroller: `useMessageScroller`,
`useMessageScrollerVisibility`, and `useMessageScrollerScrollable`. They come
from the auto-installed `@shadcn/react` dependency, so there's nothing extra to
install. Reach for them only when composition can't express what you need.
rules/composition.md›
# Component Composition
## Contents
- Items always inside their Group component
- Callouts use Alert
- Empty states use Empty component
- Toast notifications follow the project base
- Choosing between overlay components
- Dialog, Sheet, and Drawer always need a Title
- Card structure
- Button has no isPending or isLoading prop
- TabsTrigger must be inside TabsList
- Avatar always needs AvatarFallback
- Use Separator instead of raw hr or border divs
- Use Skeleton for loading placeholders
- Use Badge instead of custom styled spans
---
## Items always inside their Group component
Never render items directly inside the content container.
**Incorrect:**
```tsx
<SelectContent>
<SelectItem value="apple">Apple</SelectItem>
<SelectItem value="banana">Banana</SelectItem>
</SelectContent>
```
**Correct:**
```tsx
<SelectContent>
<SelectGroup>
<SelectItem value="apple">Apple</SelectItem>
<SelectItem value="banana">Banana</SelectItem>
</SelectGroup>
</SelectContent>
```
This applies to all group-based components:
| Item | Group |
|------|-------|
| `SelectItem`, `SelectLabel` | `SelectGroup` |
| `DropdownMenuItem`, `DropdownMenuLabel`, `DropdownMenuSub` | `DropdownMenuGroup` |
| `MenubarItem` | `MenubarGroup` |
| `ContextMenuItem` | `ContextMenuGroup` |
| `CommandItem` | `CommandGroup` |
| `MessageScrollerItem` | `MessageScrollerContent` |
| `Message` (consecutive, same sender) | `MessageGroup` |
| `Bubble` (stacked) | `BubbleGroup` |
| `Attachment` (in a row) | `AttachmentGroup` |
Chat components nest in a fixed order (`MessageScrollerProvider` → `MessageScroller` → `MessageScrollerViewport` → `MessageScrollerContent` → `MessageScrollerItem`). See [chat.md](./chat.md).
---
## Callouts use Alert
```tsx
<Alert>
<AlertTitle>Warning</AlertTitle>
<AlertDescription>Something needs attention.</AlertDescription>
</Alert>
```
---
## Empty states use Empty component
```tsx
<Empty>
<EmptyHeader>
<EmptyMedia variant="icon"><FolderIcon /></EmptyMedia>
<EmptyTitle>No projects yet</EmptyTitle>
<EmptyDescription>Get started by creating a new project.</EmptyDescription>
</EmptyHeader>
<EmptyContent>
<Button>Create Project</Button>
</EmptyContent>
</Empty>
```
---
## Toast notifications follow the project base
For Base UI projects, use the `toast` component:
```tsx
import { toast } from "@/components/ui/toast"
toast.add({
title: "Changes saved.",
})
```
For Radix and React Aria projects, use Sonner:
```tsx
import { toast } from "sonner"
toast.success("Changes saved.")
toast.error("Something went wrong.")
toast("File deleted.", {
action: { label: "Undo", onClick: () => undoDelete() },
})
```
---
## Choosing between overlay components
| Use case | Component |
|----------|-----------|
| Focused task that requires input | `Dialog` |
| Destructive action confirmation | `AlertDialog` |
| Side panel with details or filters | `Sheet` |
| Mobile-first bottom panel | `Drawer` |
| Quick info on hover | `HoverCard` |
| Small contextual content on click | `Popover` |
---
## Dialog, Sheet, and Drawer always need a Title
`DialogTitle`, `SheetTitle`, `DrawerTitle` are required for accessibility. Use `className="sr-only"` if visually hidden.
```tsx
<DialogContent>
<DialogHeader>
<DialogTitle>Edit Profile</DialogTitle>
<DialogDescription>Update your profile.</DialogDescription>
</DialogHeader>
...
</DialogContent>
```
---
## Card structure
Use full composition — don't dump everything into `CardContent`:
```tsx
<Card>
<CardHeader>
<CardTitle>Team Members</CardTitle>
<CardDescription>Manage your team.</CardDescription>
</CardHeader>
<CardContent>...</CardContent>
<CardFooter>
<Button>Invite</Button>
</CardFooter>
</Card>
```
---
## Button has no isPending or isLoading prop
Compose with `Spinner` + `data-icon` + `disabled`:
```tsx
<Button disabled>
<Spinner data-icon="inline-start" />
Saving...
</Button>
```
---
## TabsTrigger must be inside TabsList
Never render `TabsTrigger` directly inside `Tabs` — always wrap in `TabsList`:
```tsx
<Tabs defaultValue="account">
<TabsList>
<TabsTrigger value="account">Account</TabsTrigger>
<TabsTrigger value="password">Password</TabsTrigger>
</TabsList>
<TabsContent value="account">...</TabsContent>
</Tabs>
```
---
## Avatar always needs AvatarFallback
Always include `AvatarFallback` for when the image fails to load:
```tsx
<Avatar>
<AvatarImage src="/avatar.png" alt="User" />
<AvatarFallback>JD</AvatarFallback>
</Avatar>
```
---
## Use existing components instead of custom markup
| Instead of | Use |
|---|---|
| `<hr>` or `<div className="border-t">` | `<Separator />` |
| `<div className="animate-pulse">` with styled divs | `<Skeleton className="h-4 w-3/4" />` |
| `<span className="rounded-full bg-green-100 ...">` | `<Badge variant="secondary">` |
rules/forms.md›
# Forms & Inputs
## Contents
- Forms use FieldGroup + Field
- InputGroup requires InputGroupInput/InputGroupTextarea
- Buttons inside inputs use InputGroup + InputGroupAddon
- Option sets (2–7 choices) use ToggleGroup
- FieldSet + FieldLegend for grouping related fields
- Field validation and disabled states
---
## Forms use FieldGroup + Field
Always use `FieldGroup` + `Field` — never raw `div` with `space-y-*`:
```tsx
<FieldGroup>
<Field>
<FieldLabel htmlFor="email">Email</FieldLabel>
<Input id="email" type="email" />
</Field>
<Field>
<FieldLabel htmlFor="password">Password</FieldLabel>
<Input id="password" type="password" />
</Field>
</FieldGroup>
```
Use `Field orientation="horizontal"` for settings pages. Use `FieldLabel className="sr-only"` for visually hidden labels.
**Choosing form controls:**
- Simple text input → `Input`
- Dropdown with predefined options → `Select`
- Searchable dropdown → `Combobox`
- Native HTML select (no JS) → `native-select`
- Boolean toggle → `Switch` (for settings) or `Checkbox` (for forms)
- Single choice from few options → `RadioGroup`
- Toggle between 2–5 options → `ToggleGroup` + `ToggleGroupItem`
- OTP/verification code → `InputOTP`
- Multi-line text → `Textarea`
---
## InputGroup requires InputGroupInput/InputGroupTextarea
Never use raw `Input` or `Textarea` inside an `InputGroup`.
**Incorrect:**
```tsx
<InputGroup>
<Input placeholder="Search..." />
</InputGroup>
```
**Correct:**
```tsx
import { InputGroup, InputGroupInput } from "@/components/ui/input-group"
<InputGroup>
<InputGroupInput placeholder="Search..." />
</InputGroup>
```
---
## Buttons inside inputs use InputGroup + InputGroupAddon
Never place a `Button` directly inside or adjacent to an `Input` with custom positioning.
**Incorrect:**
```tsx
<div className="relative">
<Input placeholder="Search..." className="pr-10" />
<Button className="absolute right-0 top-0" size="icon">
<SearchIcon />
</Button>
</div>
```
**Correct:**
```tsx
import { InputGroup, InputGroupInput, InputGroupAddon } from "@/components/ui/input-group"
<InputGroup>
<InputGroupInput placeholder="Search..." />
<InputGroupAddon>
<Button size="icon">
<SearchIcon data-icon="inline-start" />
</Button>
</InputGroupAddon>
</InputGroup>
```
---
## Option sets (2–7 choices) use ToggleGroup
Don't manually loop `Button` components with active state.
**Incorrect:**
```tsx
const [selected, setSelected] = useState("daily")
<div className="flex gap-2">
{["daily", "weekly", "monthly"].map((option) => (
<Button
key={option}
variant={selected === option ? "default" : "outline"}
onClick={() => setSelected(option)}
>
{option}
</Button>
))}
</div>
```
**Correct:**
```tsx
import { ToggleGroup, ToggleGroupItem } from "@/components/ui/toggle-group"
<ToggleGroup spacing={2}>
<ToggleGroupItem value="daily">Daily</ToggleGroupItem>
<ToggleGroupItem value="weekly">Weekly</ToggleGroupItem>
<ToggleGroupItem value="monthly">Monthly</ToggleGroupItem>
</ToggleGroup>
```
Combine with `Field` for labelled toggle groups:
```tsx
<Field orientation="horizontal">
<FieldTitle id="theme-label">Theme</FieldTitle>
<ToggleGroup aria-labelledby="theme-label" spacing={2}>
<ToggleGroupItem value="light">Light</ToggleGroupItem>
<ToggleGroupItem value="dark">Dark</ToggleGroupItem>
<ToggleGroupItem value="system">System</ToggleGroupItem>
</ToggleGroup>
</Field>
```
> **Note:** `defaultValue` and `type`/`multiple` props differ between base and radix. See [base-vs-radix.md](./base-vs-radix.md#togglegroup).
---
## FieldSet + FieldLegend for grouping related fields
Use `FieldSet` + `FieldLegend` for related checkboxes, radios, or switches — not `div` with a heading:
```tsx
<FieldSet>
<FieldLegend variant="label">Preferences</FieldLegend>
<FieldDescription>Select all that apply.</FieldDescription>
<FieldGroup className="gap-3">
<Field orientation="horizontal">
<Checkbox id="dark" />
<FieldLabel htmlFor="dark" className="font-normal">Dark mode</FieldLabel>
</Field>
</FieldGroup>
</FieldSet>
```
---
## Field validation and disabled states
Both attributes are needed — `data-invalid`/`data-disabled` styles the field (label, description), while `aria-invalid`/`disabled` styles the control.
```tsx
// Invalid.
<Field data-invalid>
<FieldLabel htmlFor="email">Email</FieldLabel>
<Input id="email" aria-invalid />
<FieldDescription>Invalid email address.</FieldDescription>
</Field>
// Disabled.
<Field data-disabled>
<FieldLabel htmlFor="email">Email</FieldLabel>
<Input id="email" disabled />
</Field>
```
Works for all controls: `Input`, `Textarea`, `Select`, `Checkbox`, `RadioGroupItem`, `Switch`, `Slider`, `NativeSelect`, `InputOTP`.
rules/icons.md›
# Icons
**Always use the project's configured `iconLibrary` for imports.** Check the `iconLibrary` field from project context: `lucide` → `lucide-react`, `tabler` → `@tabler/icons-react`, etc. Never assume `lucide-react`.
---
## Icons in Button use data-icon attribute
Add `data-icon="inline-start"` (prefix) or `data-icon="inline-end"` (suffix) to the icon. No sizing classes on the icon.
**Incorrect:**
```tsx
<Button>
<SearchIcon className="mr-2 size-4" />
Search
</Button>
```
**Correct:**
```tsx
<Button>
<SearchIcon data-icon="inline-start"/>
Search
</Button>
<Button>
Next
<ArrowRightIcon data-icon="inline-end"/>
</Button>
```
---
## No sizing classes on icons inside components
Components handle icon sizing via CSS. Don't add `size-4`, `w-4 h-4`, or other sizing classes to icons inside `Button`, `DropdownMenuItem`, `Alert`, `Sidebar*`, or other shadcn components. Unless the user explicitly asks for custom icon sizes.
**Incorrect:**
```tsx
<Button>
<SearchIcon className="size-4" data-icon="inline-start" />
Search
</Button>
<DropdownMenuItem>
<SettingsIcon className="mr-2 size-4" />
Settings
</DropdownMenuItem>
```
**Correct:**
```tsx
<Button>
<SearchIcon data-icon="inline-start" />
Search
</Button>
<DropdownMenuItem>
<SettingsIcon />
Settings
</DropdownMenuItem>
```
---
## Pass icons as component objects, not string keys
Use `icon={CheckIcon}`, not a string key to a lookup map.
**Incorrect:**
```tsx
const iconMap = {
check: CheckIcon,
alert: AlertIcon,
}
function StatusBadge({ icon }: { icon: string }) {
const Icon = iconMap[icon]
return <Icon />
}
<StatusBadge icon="check" />
```
**Correct:**
```tsx
// Import from the project's configured iconLibrary (e.g. lucide-react, @tabler/icons-react).
import { CheckIcon } from "lucide-react"
function StatusBadge({ icon: Icon }: { icon: React.ComponentType }) {
return <Icon />
}
<StatusBadge icon={CheckIcon} />
```
rules/styling.md›
# Styling & Customization
See [customization.md](../customization.md) for theming, CSS variables, and adding custom colors.
## Contents
- Semantic colors
- Built-in variants first
- className for layout only
- No space-x-* / space-y-*
- Prefer size-* over w-* h-* when equal
- Prefer truncate shorthand
- No manual dark: color overrides
- Use cn() for conditional classes
- No manual z-index on overlay components
- Use shimmer / scroll-fade utilities, not custom animations
---
## Semantic colors
**Incorrect:**
```tsx
<div className="bg-blue-500 text-white">
<p className="text-gray-600">Secondary text</p>
</div>
```
**Correct:**
```tsx
<div className="bg-primary text-primary-foreground">
<p className="text-muted-foreground">Secondary text</p>
</div>
```
---
## No raw color values for status/state indicators
For positive, negative, or status indicators, use Badge variants, semantic tokens like `text-destructive`, or define custom CSS variables — don't reach for raw Tailwind colors.
**Incorrect:**
```tsx
<span className="text-emerald-600">+20.1%</span>
<span className="text-green-500">Active</span>
<span className="text-red-600">-3.2%</span>
```
**Correct:**
```tsx
<Badge variant="secondary">+20.1%</Badge>
<Badge>Active</Badge>
<span className="text-destructive">-3.2%</span>
```
If you need a success/positive color that doesn't exist as a semantic token, use a Badge variant or ask the user about adding a custom CSS variable to the theme (see [customization.md](../customization.md)).
---
## Built-in variants first
**Incorrect:**
```tsx
<Button className="border border-input bg-transparent hover:bg-accent">
Click me
</Button>
```
**Correct:**
```tsx
<Button variant="outline">Click me</Button>
```
---
## className for layout only
Use `className` for layout (e.g. `max-w-md`, `mx-auto`, `mt-4`), **not** for overriding component colors or typography. To change colors, use semantic tokens, built-in variants, or CSS variables.
**Incorrect:**
```tsx
<Card className="bg-blue-100 text-blue-900 font-bold">
<CardContent>Dashboard</CardContent>
</Card>
```
**Correct:**
```tsx
<Card className="max-w-md mx-auto">
<CardContent>Dashboard</CardContent>
</Card>
```
To customize a component's appearance, prefer these approaches in order:
1. **Built-in variants** — `variant="outline"`, `variant="destructive"`, etc.
2. **Semantic color tokens** — `bg-primary`, `text-muted-foreground`.
3. **CSS variables** — define custom colors in the global CSS file (see [customization.md](../customization.md)).
---
## No space-x-* / space-y-*
Use `gap-*` instead. `space-y-4` → `flex flex-col gap-4`. `space-x-2` → `flex gap-2`.
```tsx
<div className="flex flex-col gap-4">
<Input />
<Input />
<Button>Submit</Button>
</div>
```
---
## Prefer size-* over w-* h-* when equal
`size-10` not `w-10 h-10`. Applies to icons, avatars, skeletons, etc.
---
## Prefer truncate shorthand
`truncate` not `overflow-hidden text-ellipsis whitespace-nowrap`.
---
## No manual dark: color overrides
Use semantic tokens — they handle light/dark via CSS variables. `bg-background text-foreground` not `bg-white dark:bg-gray-950`.
---
## Use cn() for conditional classes
Use the `cn()` utility from the project for conditional or merged class names. Don't write manual ternaries in className strings.
**Incorrect:**
```tsx
<div className={`flex items-center ${isActive ? "bg-primary text-primary-foreground" : "bg-muted"}`}>
```
**Correct:**
```tsx
import { cn } from "cn"
<div className={cn("flex items-center", isActive ? "bg-primary text-primary-foreground" : "bg-muted")}>
```
---
## No manual z-index on overlay components
`Dialog`, `Sheet`, `Drawer`, `AlertDialog`, `DropdownMenu`, `Popover`, `Tooltip`, `HoverCard` handle their own stacking. Never add `z-50` or `z-[999]`.
---
## Use shimmer / scroll-fade utilities, not custom animations
For a live "thinking…" or loading-text shimmer, apply the `shimmer` utility. Don't author a custom `@keyframes` or a `bg-clip-text` gradient sweep.
For scroll-aware edge fading on a scroll container, use `scroll-fade` (and the axis variants `scroll-fade-x` / `scroll-fade-b`). Don't hand-roll mask gradients. The chat components already apply these internally: `Attachment` shimmers its title during upload, and `MessageScrollerViewport` fades its edges.
**Incorrect:**
```tsx
<span className="animate-pulse bg-gradient-to-r from-muted-foreground/40 via-foreground/70 to-muted-foreground/40 bg-clip-text text-transparent [animation:shimmer_1.6s_infinite]">
Thinking…
</span>
```
**Correct:**
```tsx
<span className="shimmer">Thinking…</span>
```
scripts/showcase-coverage.mjs›
#!/usr/bin/env node
// Lists installed UI components that no file in the showcase imports.
// Usage: node showcase-coverage.mjs <ui-dir> <showcase-dir...>
import { readdirSync, readFileSync, statSync } from "node:fs"
import { basename, extname, join, resolve } from "node:path"
const [uiArg, ...roots] = process.argv.slice(2)
if (!uiArg || roots.length === 0) {
console.error("Usage: node showcase-coverage.mjs <ui-dir> <showcase-dir...>")
process.exit(1)
}
const uiDir = resolve(uiArg)
const components = readdirSync(uiDir)
.filter((file) => [".tsx", ".ts"].includes(extname(file)))
.map((file) => basename(file, extname(file)))
function walk(path) {
if (statSync(path).isFile()) {
return [path]
}
return readdirSync(path).flatMap((entry) => {
const child = join(path, entry)
// Skip the ui directory so components don't count as using each other.
if (entry === "node_modules" || child === uiDir) {
return []
}
return walk(child)
})
}
const source = roots
.map((root) => resolve(root))
.flatMap(walk)
.filter((file) => /\.(tsx?|jsx?)$/.test(file))
.map((file) => readFileSync(file, "utf8"))
.join("\n")
const missing = components.filter(
(name) => !new RegExp(`/ui/${name}["']`).test(source)
)
console.log(
`${components.length - missing.length}/${components.length} components shown.`
)
if (missing.length > 0) {
console.log(`Missing: ${missing.join(", ")}`)
process.exit(1)
}
SKILL.md›
---
name: shadcn
description: Manages shadcn components and projects — adding, searching, fixing, debugging, styling, and composing UI, including chat interfaces. Provides project context, component docs, and usage examples. Applies when working with shadcn/ui, component registries, presets, --preset codes, or any project with a components.json file. Also triggers for "shadcn init", "create an app with --preset", "switch to --preset", and for building a design system or applying a DESIGN.md or brand spec to shadcn/ui.
user-invocable: false
allowed-tools: Bash(npx shadcn@latest *), Bash(pnpm dlx shadcn@latest *), Bash(bunx --bun shadcn@latest *)
---
# shadcn/ui
A framework for building ui, components and design systems. Components are added as source code to the user's project via the CLI.
> **IMPORTANT:** Run all CLI commands using the project's package runner: `npx shadcn@latest`, `pnpm dlx shadcn@latest`, or `bunx --bun shadcn@latest` — based on the project's `packageManager`. Examples below use `npx shadcn@latest` but substitute the correct runner for the project.
## Current Project Context
```json
!`npx shadcn@latest info --json`
```
The JSON above contains the project config and installed components. Use `npx shadcn@latest docs <component>` to get documentation and example URLs for any component.
## Principles
1. **Use existing components first.** Use `npx shadcn@latest search` to check registries before writing custom UI. Check community registries too.
2. **Compose, don't reinvent.** Settings page = Tabs + Card + form controls. Dashboard = Sidebar + Card + Chart + Table.
3. **Use built-in variants before custom styles.** `variant="outline"`, `size="sm"`, etc.
4. **Use semantic colors.** `bg-primary`, `text-muted-foreground` — never raw values like `bg-blue-500`.
## Critical Rules
These rules are **always enforced**. Each links to a file with Incorrect/Correct code pairs.
### Styling & Tailwind → [styling.md](./rules/styling.md)
- **`className` for layout, not styling.** Never override component colors or typography.
- **No `space-x-*` or `space-y-*`.** Use `flex` with `gap-*`. For vertical stacks, `flex flex-col gap-*`.
- **Use `size-*` when width and height are equal.** `size-10` not `w-10 h-10`.
- **Use `truncate` shorthand.** Not `overflow-hidden text-ellipsis whitespace-nowrap`.
- **No manual `dark:` color overrides.** Use semantic tokens (`bg-background`, `text-muted-foreground`).
- **Use `cn()` for conditional classes.** Don't write manual template literal ternaries.
- **No manual `z-index` on overlay components.** Dialog, Sheet, Popover, etc. handle their own stacking.
### Forms & Inputs → [forms.md](./rules/forms.md)
- **Forms use `FieldGroup` + `Field`.** Never use raw `div` with `space-y-*` or `grid gap-*` for form layout.
- **`InputGroup` uses `InputGroupInput`/`InputGroupTextarea`.** Never raw `Input`/`Textarea` inside `InputGroup`.
- **Buttons inside inputs use `InputGroup` + `InputGroupAddon`.**
- **Option sets (2–7 choices) use `ToggleGroup`.** Don't loop `Button` with manual active state.
- **`FieldSet` + `FieldLegend` for grouping related checkboxes/radios.** Don't use a `div` with a heading.
- **Field validation uses `data-invalid` + `aria-invalid`.** `data-invalid` on `Field`, `aria-invalid` on the control. For disabled: `data-disabled` on `Field`, `disabled` on the control.
### Component Structure → [composition.md](./rules/composition.md)
- **Items always inside their Group.** `SelectItem` → `SelectGroup`. `DropdownMenuItem` → `DropdownMenuGroup`. `CommandItem` → `CommandGroup`.
- **Use `asChild` (radix) or `render` (base) for custom triggers.** Check `base` field from `npx shadcn@latest info`. → [base-vs-radix.md](./rules/base-vs-radix.md)
- **Dialog, Sheet, and Drawer always need a Title.** `DialogTitle`, `SheetTitle`, `DrawerTitle` required for accessibility. Use `className="sr-only"` if visually hidden.
- **Use full Card composition.** `CardHeader`/`CardTitle`/`CardDescription`/`CardContent`/`CardFooter`. Don't dump everything in `CardContent`.
- **Button has no `isPending`/`isLoading`.** Compose with `Spinner` + `data-icon` + `disabled`.
- **`TabsTrigger` must be inside `TabsList`.** Never render triggers directly in `Tabs`.
- **`Avatar` always needs `AvatarFallback`.** For when the image fails to load.
### Use Components, Not Custom Markup → [composition.md](./rules/composition.md)
- **Use existing components before custom markup.** Check if a component exists before writing a styled `div`.
- **Callouts use `Alert`.** Don't build custom styled divs.
- **Empty states use `Empty`.** Don't build custom empty state markup.
- **Toast follows the project base.** Use `toast` from the `toast` component for
Base UI projects. Use `toast()` from `sonner` for Radix and React Aria
projects.
- **Use `Separator`** instead of `<hr>` or `<div className="border-t">`.
- **Use `Skeleton`** for loading placeholders. No custom `animate-pulse` divs.
- **Use `Badge`** instead of custom styled spans.
### Icons → [icons.md](./rules/icons.md)
- **Icons in `Button` use `data-icon`.** `data-icon="inline-start"` or `data-icon="inline-end"` on the icon.
- **No sizing classes on icons inside components.** Components handle icon sizing via CSS. No `size-4` or `w-4 h-4`.
- **Pass icons as objects, not string keys.** `icon={CheckIcon}`, not a string lookup.
### Chat & Messaging → [chat.md](./rules/chat.md)
- **Chat UI composes the chat primitives.** Conversations use `MessageScroller`, rows use `Message`, surfaces use `Bubble`. Never hand-rolled bubble `div`s or a raw scroll container.
- **`MessageScroller` owns scroll behavior.** Streaming follow, anchoring, and jump-to-latest (`MessageScrollerButton`) are built in. Don't write a `useStickToBottom`/`ResizeObserver` hook.
- **Attachments use `Attachment`; system notes and dividers use `Marker`.** Not `Item` cards or `Separator` + a label.
- **Assistant activity uses `Trace`.** Reasoning, tool calls, sources and steps are `TraceLine`s in a `Trace`, one `Trace` per run of message parts. Behavior wraps the line: `TraceCollapsible`, a sheet trigger or a link. Not a hand-rolled `Collapsible` or a `Marker`.
### CLI
- **Never decode preset codes or build preset URLs manually.** Use `npx shadcn@latest preset decode <code>`, `preset url <code>`, or `preset open <code>`. For project-aware preset detection, use `npx shadcn@latest preset resolve`.
- **Apply preset codes directly with the CLI.** Use `npx shadcn@latest apply <code>` for existing projects, or `npx shadcn@latest init --preset <code>` when initializing.
## Key Patterns
These are the most common patterns that differentiate correct shadcn/ui code. For edge cases, see the linked rule files above.
```tsx
// Form layout: FieldGroup + Field, not div + Label.
<FieldGroup>
<Field>
<FieldLabel htmlFor="email">Email</FieldLabel>
<Input id="email" />
</Field>
</FieldGroup>
// Validation: data-invalid on Field, aria-invalid on the control.
<Field data-invalid>
<FieldLabel>Email</FieldLabel>
<Input aria-invalid />
<FieldDescription>Invalid email.</FieldDescription>
</Field>
// Icons in buttons: data-icon, no sizing classes.
<Button>
<SearchIcon data-icon="inline-start" />
Search
</Button>
// Spacing: gap-*, not space-y-*.
<div className="flex flex-col gap-4"> // correct
<div className="space-y-4"> // wrong
// Equal dimensions: size-*, not w-* h-*.
<Avatar className="size-10"> // correct
<Avatar className="w-10 h-10"> // wrong
// Status colors: Badge variants or semantic tokens, not raw colors.
<Badge variant="secondary">+20.1%</Badge> // correct
<span className="text-emerald-600">+20.1%</span> // wrong
```
## Component Selection
| Need | Use |
| -------------------------- | --------------------------------------------------------------------------------------------------- |
| Button/action | `Button` with appropriate variant |
| Form inputs | `Input`, `Select`, `Combobox`, `Switch`, `Checkbox`, `RadioGroup`, `Textarea`, `InputOTP`, `Slider` |
| Toggle between 2–5 options | `ToggleGroup` + `ToggleGroupItem` |
| Data display | `Table`, `Card`, `Badge`, `Avatar` |
| Navigation | `Sidebar`, `NavigationMenu`, `Breadcrumb`, `Tabs`, `Pagination` |
| Overlays | `Dialog` (modal), `Sheet` (side panel), `Drawer` (bottom sheet), `AlertDialog` (confirmation) |
| Feedback | `toast` (Base UI), `sonner` (Radix/Aria), `Alert`, `Progress`, `Skeleton`, `Spinner` |
| Command palette | `Command` inside `Dialog` |
| Charts | `Chart` (wraps Recharts) |
| Layout | `Card`, `Separator`, `Resizable`, `ScrollArea`, `Accordion`, `Collapsible` |
| Empty states | `Empty` |
| Menus | `DropdownMenu`, `ContextMenu`, `Menubar` |
| Tooltips/info | `Tooltip`, `HoverCard`, `Popover` |
| Chat / conversation UI | `MessageScroller`, `Message`, `Bubble`, `Attachment`, `Marker`, `Trace` |
## Key Fields
The injected project context contains these key fields:
- **`aliases`** → use the actual alias prefix for imports (e.g. `@/`, `~/`), never hardcode.
- **`isRSC`** → when `true`, components using `useState`, `useEffect`, event handlers, or browser APIs need `"use client"` at the top of the file. Always reference this field when advising on the directive.
- **`tailwindVersion`** → `"v4"` uses `@theme inline` blocks; `"v3"` uses `tailwind.config.js`.
- **`tailwindCssFile`** → the global CSS file where custom CSS variables are defined. Always edit this file, never create a new one.
- **`style`** → component visual treatment (e.g. `nova`, `vega`).
- **`base`** → primitive library (`radix` or `base`). Affects component APIs and available props.
- **`iconLibrary`** → determines icon imports. Use `lucide-react` for `lucide`, `@tabler/icons-react` for `tabler`, etc. Never assume `lucide-react`.
- **`resolvedPaths`** → exact file-system destinations for components, utils, hooks, etc.
- **`framework`** → routing and file conventions (e.g. Next.js App Router vs Vite SPA).
- **`packageManager`** → use this for any non-shadcn dependency installs (e.g. `pnpm add date-fns` vs `npm install date-fns`).
- **`preset`** → resolved preset code and values for the current project. Use `npx shadcn@latest preset resolve --json` when you only need preset information.
See [cli.md — `info` command](./cli.md) for the full field reference.
## Component Docs, Examples, and Usage
Run `npx shadcn@latest docs <component>` to get the URLs for a component's documentation, examples, and API reference. Fetch these URLs to get the actual content.
```bash
npx shadcn@latest docs button dialog select
```
**When creating, fixing, debugging, or using a component, always run `npx shadcn@latest docs` and fetch the URLs first.** This ensures you're working with the correct API and usage patterns rather than guessing.
## Workflow
1. **Get project context** — already injected above. Run `npx shadcn@latest info` again if you need to refresh.
2. **Check installed components first** — before running `add`, always check the `components` list from project context or list the `resolvedPaths.ui` directory. Don't import components that haven't been added, and don't re-add ones already installed.
3. **Find components** — `npx shadcn@latest search`.
4. **Get docs and examples** — run `npx shadcn@latest docs <component>` to get URLs, then fetch them. Use `npx shadcn@latest view` to browse registry items you haven't installed. To preview changes to installed components, use `npx shadcn@latest add --diff`.
5. **Install or update** — `npx shadcn@latest add`. When updating existing components, use `--dry-run` and `--diff` to preview changes first (see [Updating Components](#updating-components) below).
6. **Fix imports in third-party components** — After adding components from community registries (e.g. `@bundui`, `@magicui`), check the added non-UI files for hardcoded import paths like `@/components/ui/...`. These won't match the project's actual aliases. Use `npx shadcn@latest info` to get the correct `ui` alias (e.g. `@workspace/ui/components`) and rewrite the imports accordingly. The CLI rewrites imports for its own UI files, but third-party registry components may use default paths that don't match the project.
7. **Review added components** — After adding a component or block from any registry, **always read the added files and verify they are correct**. Check for missing sub-components (e.g. `SelectItem` without `SelectGroup`), missing imports, incorrect composition, or violations of the [Critical Rules](#critical-rules). Also replace any icon imports with the project's `iconLibrary` from the project context (e.g. if the registry item uses `lucide-react` but the project uses `hugeicons`, swap the imports and icon names accordingly). Fix all issues before moving on.
8. **Registry must be explicit** — When the user asks to add a block or component, **do not guess the registry**. If no registry is specified (e.g. user says "add a login block" without specifying `@shadcn`, `@tailark`, `owner/repo`, etc.), ask which registry to use. Never default to a registry on behalf of the user.
9. **Switching presets** — Ask the user first: **overwrite**, **partial**, **merge**, or **skip**?
- **Inspect current preset**: `npx shadcn@latest preset resolve`. Use `--json` when you need structured values.
- **Inspect incoming preset**: `npx shadcn@latest preset decode <code>`. Use `preset url <code>` or `preset open <code>` to share or open the preset builder.
- **Overwrite**: `npx shadcn@latest apply <code>`. Overwrites detected components, fonts, and CSS variables.
- **Partial**: `npx shadcn@latest apply <code> --only theme,font`. Updates only the selected preset parts without reinstalling UI components. Supported values are `theme` and `font`; comma-separated combinations are allowed. `icon` is intentionally not supported, because icon changes may require full component reinstall and transforms.
- **Merge**: `npx shadcn@latest init --preset <code> --force --no-reinstall`, then run `npx shadcn@latest info` to list installed components, then for each installed component use `--dry-run` and `--diff` to [smart merge](#updating-components) it individually.
- **Skip**: `npx shadcn@latest init --preset <code> --force --no-reinstall`. Only updates config and CSS, leaves components as-is.
- **Important**: Always run preset commands inside the user's project directory. `apply` only works in an existing project with a `components.json` file. The CLI automatically preserves the current base (`base` vs `radix`) from `components.json`. If you must use a scratch/temp directory (e.g. for `--dry-run` comparisons), pass `--base <current-base>` explicitly — preset codes do not encode the base.
## Design Systems from DESIGN.md
When the user asks for a design system from a `DESIGN.md` (or a brand spec), with or without a preset, follow [design-system.md](./design-system.md) end to end:
1. `init --preset <code> --template <vite|next> --name <app> --no-monorepo -y`. Without a preset code, pick the closest style and pass `--base base --preset <style>`. Then `add --all -y`.
2. Read the DESIGN.md frontmatter, Do's and Don'ts, and Known Gaps before editing.
3. Map its tokens onto the shadcn variables in `tailwindCssFile`. Pin the radius scale, shadows, fonts and `type-*` utilities.
4. Restyle components by editing their `cva` variants. Change control heights together.
5. Build the design system page per [design-system-page.md](./design-system-page.md): contrast-checked color roles, type specimens, pinned state matrices, edge cases, do/don't pairs, recipes. Check coverage with `scripts/showcase-coverage.mjs`.
6. Verify in a browser: typecheck, no console errors, loads at the top, no horizontal overflow, dark mode.
## Updating Components
When the user asks to update a component from upstream while keeping their local changes, use `--dry-run` and `--diff` to intelligently merge. **NEVER fetch raw files from GitHub manually — always use the CLI.**
1. Run `npx shadcn@latest add <component> --dry-run` to see all files that would be affected.
2. For each file, run `npx shadcn@latest add <component> --diff <file>` to see what changed upstream vs local.
3. Decide per file based on the diff:
- No local changes → safe to overwrite.
- Has local changes → read the local file, analyze the diff, and apply upstream updates while preserving local modifications.
- User says "just update everything" → use `--overwrite`, but confirm first.
4. **Never use `--overwrite` without the user's explicit approval.**
## Quick Reference
```bash
# Create a new project.
npx shadcn@latest init --name my-app --preset base-nova
npx shadcn@latest init --name my-app --preset a2r6bw --template vite
# Create a design system app (then follow design-system.md).
npx shadcn@latest init --name my-ds --preset b0 --template vite --no-monorepo -y
npx shadcn@latest init --name my-ds --base base --preset maia --template vite --no-monorepo -y
npx shadcn@latest add --all -y
# Create a monorepo project.
npx shadcn@latest init --name my-app --preset base-nova --monorepo
npx shadcn@latest init --name my-app --preset base-nova --template next --monorepo
# Initialize existing project.
npx shadcn@latest init --preset base-nova
npx shadcn@latest init --defaults # shortcut: --template=next --preset=nova (base style implied)
# Apply a preset to an existing project.
npx shadcn@latest apply a2r6bw
npx shadcn@latest apply a2r6bw --only theme
npx shadcn@latest apply a2r6bw --only font
npx shadcn@latest apply a2r6bw --only theme,font
# Inspect preset codes and project preset state.
npx shadcn@latest preset decode a2r6bw
npx shadcn@latest preset url a2r6bw
npx shadcn@latest preset open a2r6bw
npx shadcn@latest preset resolve
npx shadcn@latest preset resolve --json
# Add components.
npx shadcn@latest add button card dialog
npx shadcn@latest add @magicui/shimmer-button
npx shadcn@latest add owner/repo/item
npx shadcn@latest add --all
# Preview changes before adding/updating.
npx shadcn@latest add button --dry-run
npx shadcn@latest add button --diff button.tsx
npx shadcn@latest add @acme/form --view button.tsx
npx shadcn@latest add owner/repo/item --dry-run
# Search registries.
npx shadcn@latest search @shadcn -q "sidebar"
npx shadcn@latest search @tailark -q "stats"
npx shadcn@latest search owner/repo -q "login"
npx shadcn@latest search # all configured registries
npx shadcn@latest search @shadcn -q "menu" -t ui # filter by item type
# Get component docs and example URLs.
npx shadcn@latest docs button dialog select
# View registry item details (for items not yet installed).
npx shadcn@latest view @shadcn/button
npx shadcn@latest view owner/repo/item
```
**Named presets:** `nova`, `vega`, `maia`, `lyra`, `mira`, `luma`
**Templates:** `next`, `vite`, `start`, `react-router`, `astro` (all support `--monorepo`) and `laravel` (not supported for monorepo)
**Preset codes:** Version-prefixed base62 strings (e.g. `a2r6bw` or `b0`), from [ui.shadcn.com](https://ui.shadcn.com).
## Detailed References
- [rules/forms.md](./rules/forms.md) — FieldGroup, Field, InputGroup, ToggleGroup, FieldSet, validation states
- [rules/composition.md](./rules/composition.md) — Groups, overlays, Card, Tabs, Avatar, Alert, Empty, Toast, Separator, Skeleton, Badge, Button loading
- [rules/chat.md](./rules/chat.md) — MessageScroller, Message, Bubble, Attachment, Marker, Trace; streaming, anchoring, jump-to-latest, assistant activity rows
- [rules/icons.md](./rules/icons.md) — data-icon, icon sizing, passing icons as objects
- [rules/styling.md](./rules/styling.md) — Semantic colors, variants, className, spacing, size, truncate, dark mode, cn(), z-index
- [rules/base-vs-radix.md](./rules/base-vs-radix.md) — asChild vs render, Select, ToggleGroup, Slider, Accordion
- [cli.md](./cli.md) — Commands, flags, presets, templates
- [registry.md](./registry.md) — Authoring source registries, `include`, item definitions, dependencies, GitHub registry rules
- [customization.md](./customization.md) — Theming, CSS variables, extending components
- [design-system.md](./design-system.md): DESIGN.md (with or without a preset) to a themed app: style picking, token mapping, radius, fonts, type scale, control heights, showcase traps, verification
- [design-system-page.md](./design-system-page.md): What goes on a design system page and how: foundations, component tiers, pinned state matrices, contrast pairs, edge cases, do/don't, recipes