
Shadcn
- 5.9k installs
- 120k repo stars
- Updated July 31, 2026
- shadcn-ui/ui
This is a copy of shadcn by shadcn - installs and ranking accrue to the original listing.
shadcn is an agent skill that manages shadcn/ui components via the CLI for developers who add, search, customize, and debug accessible UI primitives from components.json registries.
About
shadcn from shadcn-ui/ui is the official agent skill for shadcn/ui CLI workflows reading components.json and installed component context via npx shadcn@latest info --json. It enforces using the project package runner—npx, pnpm dlx, or bunx—and documents add, search, docs, init, and preset flows without inventing undocumented flags. Principles prioritize existing registry components over custom UI, composition with Tabs plus Card patterns, built-in variants, and semantic Tailwind tokens like bg-primary instead of raw bg-blue-500. Critical styling rules ban space-x/y in favor of flex gap, require cn() for conditional classes, and forbid manual z-index on overlays. With 4,192 catalog installs, developers reach for shadcn when initializing a design system preset, adding registry components, debugging component styling, or composing dashboards and chat interfaces from source-copied primitives—not for non-shadcn component libraries.
- Manages shadcn/ui components — adding, searching, fixing, debugging, styling, and composing UI
- Supports init, add (with dry-run and smart merge), search, view, apply, build and info commands
- Works with Next.js, Vite, Astro, React Router and other React templates
- Reads configuration from components.json and auto-detects package manager
- Enables consistent, customizable, accessible component workflows across projects
Shadcn by the numbers
- 5,930 all-time installs (skills.sh)
- +429 installs in the week ending Jul 29, 2026 (Skillselion tracking)
- Data as of Jul 31, 2026 (Skillselion catalog sync)
npx skills add https://github.com/shadcn-ui/ui --skill shadcnAdd your badge
Show developers this skill is listed on Skillselion. Paste this into your README.
| Installs | 5.9k |
|---|---|
| repo stars | ★ 120k |
| Last updated | July 31, 2026 |
| Repository | shadcn-ui/ui ↗ |
How do you add shadcn/ui components to a project?
Add, customize, search, and maintain high-quality accessible UI components without leaving their codebase.
Who is it for?
React developers using shadcn/ui who need CLI-guided component adds, registry search, styling rule compliance, and composition patterns.
Skip if: Projects on Material UI or Ant Design exclusively, or teams with no components.json and no intent to adopt shadcn/ui primitives.
When should I use this skill?
User mentions shadcn, shadcn/ui, components.json, npx shadcn@latest, component registries, presets, or asks to add or fix shadcn components.
What you get
Installed source components under the project tree, updated components.json config, registry search results, and CLI-aligned styling fixes.
- Installed UI components
- Updated components.json
- Registry search results
By the numbers
- 4,192 catalog installs in Skillselion source metadata
- Supports 3 package runners: npx, pnpm dlx, and bunx shadcn@latest
- Components copied as source into the project via components.json registries
Files
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, orbunx --bun shadcn@latest— based on the project'spackageManager. Examples below usenpx shadcn@latestbut substitute the correct runner for the project.
Current Project Context
!`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
- `className` for layout, not styling. Never override component colors or typography.
- *No `space-x-
orspace-y-`. Use `flex` with `gap-. For vertical stacks,flex flex-col gap-*`. - *Use `size-
when width and height are equal.**size-10notw-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
- Forms use `FieldGroup` + `Field`. Never use raw
divwithspace-y-*orgrid gap-*for form layout. - `InputGroup` uses `InputGroupInput`/`InputGroupTextarea`. Never raw
Input/TextareainsideInputGroup. - Buttons inside inputs use `InputGroup` + `InputGroupAddon`.
- Option sets (2–7 choices) use `ToggleGroup`. Don't loop
Buttonwith manual active state. - `FieldSet` + `FieldLegend` for grouping related checkboxes/radios. Don't use a
divwith a heading. - Field validation uses `data-invalid` + `aria-invalid`.
data-invalidonField,aria-invalidon the control. For disabled:data-disabledonField,disabledon the control.
Component Structure → composition.md
- Items always inside their Group.
SelectItem→SelectGroup.DropdownMenuItem→DropdownMenuGroup.CommandItem→CommandGroup. - Use `asChild` (radix) or `render` (base) for custom triggers. Check
basefield fromnpx shadcn@latest info. → base-vs-radix.md - Dialog, Sheet, and Drawer always need a Title.
DialogTitle,SheetTitle,DrawerTitlerequired for accessibility. UseclassName="sr-only"if visually hidden. - Use full Card composition.
CardHeader/CardTitle/CardDescription/CardContent/CardFooter. Don't dump everything inCardContent. - 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
- 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 via `sonner`. Use
toast()fromsonner. - Use `Separator` instead of
<hr>or<div className="border-t">. - Use `Skeleton` for loading placeholders. No custom
animate-pulsedivs. - Use `Badge` instead of custom styled spans.
Icons → icons.md
- Icons in `Button` use `data-icon`.
data-icon="inline-start"ordata-icon="inline-end"on the icon. - No sizing classes on icons inside components. Components handle icon sizing via CSS. No
size-4orw-4 h-4. - Pass icons as objects, not string keys.
icon={CheckIcon}, not a string lookup.
CLI
- Never decode preset codes or build preset URLs manually. Use
npx shadcn@latest preset decode <code>,preset url <code>, orpreset open <code>. For project-aware preset detection, usenpx shadcn@latest preset resolve. - Apply preset codes directly with the CLI. Use
npx shadcn@latest apply <code>for existing projects, ornpx 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.
// 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> // wrongComponent 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 | sonner (toast), 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 |
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 usinguseState,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 inlineblocks;"v3"usestailwind.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 (
radixorbase). Affects component APIs and available props. - `iconLibrary` → determines icon imports. Use
lucide-reactforlucide,@tabler/icons-reactfortabler, etc. Never assumelucide-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-fnsvsnpm install date-fns). - `preset` → resolved preset code and values for the current project. Use
npx shadcn@latest preset resolve --jsonwhen you only need preset information.
See cli.md — `info` command 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.
npx shadcn@latest docs button dialog selectWhen 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 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. 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--jsonwhen you need structured values. - Inspect incoming preset:
npx shadcn@latest preset decode <code>. Usepreset url <code>orpreset 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 arethemeandfont; comma-separated combinations are allowed.iconis intentionally not supported, because icon changes may require full component reinstall and transforms. - Merge:
npx shadcn@latest init --preset <code> --force --no-reinstall, then runnpx shadcn@latest infoto list installed components, then for each installed component use--dry-runand--diffto smart merge 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.
applyonly works in an existing project with acomponents.jsonfile. The CLI automatically preserves the current base (basevsradix) fromcomponents.json. If you must use a scratch/temp directory (e.g. for--dry-runcomparisons), pass--base <current-base>explicitly — preset codes do not encode the base.
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
# 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 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"
# 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/itemNamed 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.
Detailed References
- rules/forms.md — FieldGroup, Field, InputGroup, ToggleGroup, FieldSet, validation states
- rules/composition.md — Groups, overlays, Card, Tabs, Avatar, Alert, Empty, Toast, Separator, Skeleton, Badge, Button loading
- rules/icons.md — data-icon, icon sizing, passing icons as objects
- rules/styling.md — Semantic colors, variants, className, spacing, size, truncate, dark mode, cn(), z-index
- rules/base-vs-radix.md — asChild vs render, Select, ToggleGroup, Slider, Accordion
- cli.md — Commands, flags, presets, templates
- registry.md — Authoring source registries,
include, item definitions, dependencies, GitHub registry rules - customization.md — Theming, CSS variables, extending components
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"
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, orbunx --bun shadcn@latest. CheckpackageManagerfrom project context to choose the right one. Examples below usenpx shadcn@latestbut 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
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
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 usenpx 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.
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.
# 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.cssWhen 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
--diffto 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
--viewto inspect the source.
`npx shadcn@latest add --dry-run` vs `npx shadcn@latest view`: Prefernpx shadcn@latest add --dry-run/--diff/--viewovernpx shadcn@latest viewwhen the user wants to preview changes to their project.npx shadcn@latest viewonly shows raw registry metadata.npx shadcn@latest add --dry-runshows exactly what would happen in the user's project: resolved file paths, diffs against existing files, and CSS updates. Usenpx shadcn@latest viewonly when the user wants to browse registry info without a project context.
Smart Merge from Upstream
See Updating Components in SKILL.md for the full workflow.
search — Search registries
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.
| Flag | Short | Description | Default |
|---|---|---|---|
--query <query> | -q | Search query | — |
--limit <number> | -l | Max items per registry | 100 |
--offset <number> | -o | Items to skip | 0 |
--cwd <cwd> | -c | Working directory | current |
view — View item details
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
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.tsxSome 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
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
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.
| 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 runnpx shadcn@latest infoto get the list of installed components and use the smart merge workflow 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 & 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:
import { ThemeProvider } from "next-themes"
<ThemeProvider attribute="class" defaultTheme="system" enableSystem>
{children}
</ThemeProvider>---
Changing the Theme
# 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.
/* 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);
}/* 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:
// 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>)",
},
},
},
}// 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)).
---
Customizing Components
See also: rules/styling.md for Incorrect/Correct examples.
Prefer these approaches in order:
1. Built-in variants
<Button variant="outline" size="sm">
Click
</Button>2. Tailwind classes via className
<Card className="mx-auto max-w-md">...</Card>3. Add a new variant
Edit the component source to add a variant via cva:
// 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:
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
npx shadcn@latest add button --diffTo preview exactly what would change before updating, use --dry-run and --diff:
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 fileSee Updating Components in SKILL.md for the full smart merge workflow.
{
"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-*"
]
}
]
}
shadcn MCP Server
The CLI includes an MCP server that lets AI assistants search, browse, view, and install items from registries.
---
Setup
shadcn mcp # start the MCP server (stdio)
shadcn mcp init # write config for your editorEditor 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.
Input: registries (string[]), limit (number, optional), offset (number, optional)
shadcn:search_items_in_registries
Fuzzy search across registries. Registries can be configured namespaces, public GitHub sources, or registry catalog URLs.
Input: registries (string[]), query (string), limit (number, optional), 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.
Input: registries (string[]), 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.
{
"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}. ${VAR}references are resolved from environment variables.
Community registry index: https://ui.shadcn.com/r/registries.json
Registry Authoring and Addresses
Use this reference when the user wants to create, fix, publish, or reason about a shadcn registry.
Mental Model
A registry has two forms:
- Source registry: an authored
registry.jsonin a project or repository.
It may use include and file paths that point at source files.
- Built registry: generated JSON files served to CLI consumers, usually
from public/r. Use npx shadcn@latest build to create this form.
The CLI installer consumes registry item payloads. A source registry is a way to author those payloads from real files.
Registry items are not limited to React components. They can distribute components, hooks, utilities, design tokens, pages, config files, docs, rules, workflows, templates, MCP files, and other project files.
Root registry.json
The root registry file should define registry metadata and either items or include.
{
"$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.jsonmust includenameandhomepage. itemsis an array of registry item definitions.includemay be used to split the source registry into multiple files.- Included registry files may omit
nameandhomepage.
Include
Use include to keep large registries modular.
{
"$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.jsonthat declares them. - Include paths must explicitly point to a
registry.jsonfile. - 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:
{
"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:
{
"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 asregistry: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, anddocs: optional install-time
additions.
File rules:
- File paths are relative to the declaring
registry.json. registry:fileandregistry:pagefiles require atarget.- 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.
{
"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#refwhen needed. - Refs are not inherited. If
owner/repo/foo#v2depends onbarfrom 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.
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.
includefollows the same source-registry rules as local registries.- Currently, GitHub addresses support public
github.comrepositories 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:
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 SHAThis 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:
npx shadcn@latest build
npx shadcn@latest build registry.json --output public/rUse CLI commands to inspect the result:
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.jsonUse GitHub addresses directly for public GitHub registries:
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/repoWhen 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.
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:
<DialogTrigger>
<div>
<Button>Open</Button>
</div>
</DialogTrigger>Correct (radix):
<DialogTrigger asChild>
<Button>Open</Button>
</DialogTrigger>Correct (base):
<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}.
<Button render={<a href="/docs" />}>Read the docs</Button>Correct (base):
<Button render={<a href="/docs" />} nativeButton={false}>
Read the docs
</Button>Correct (radix):
<Button asChild>
<a href="/docs">Read the docs</a>
</Button>Same for triggers whose render is not a Button:
// 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):
<Select>
<SelectTrigger><SelectValue placeholder="Select a fruit" /></SelectTrigger>
</Select>Correct (base):
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):
<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.
// 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):
<Select items={items} multiple defaultValue={[]}>
<SelectTrigger>
<SelectValue>
{(value: string[]) => value.length === 0 ? "Select fruits" : `${value.length} selected`}
</SelectValue>
</SelectTrigger>
...
</Select>Correct (base — object values):
<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):
<ToggleGroup type="single" defaultValue="daily">
<ToggleGroupItem value="daily">Daily</ToggleGroupItem>
</ToggleGroup>Correct (base):
// 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):
// 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:
// 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):
<Slider defaultValue={[50]} max={100} step={1} />Correct (base):
<Slider defaultValue={50} max={100} step={1} />Correct (radix):
<Slider defaultValue={[50]} max={100} step={1} />Both use arrays for range sliders. Controlled onValueChange in base may need a cast:
// 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):
<Accordion type="single" collapsible defaultValue="item-1">
<AccordionItem value="item-1">...</AccordionItem>
</Accordion>Correct (base):
<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):
<Accordion type="single" collapsible defaultValue="item-1">
<AccordionItem value="item-1">...</AccordionItem>
</Accordion>Component Composition
Contents
- Items always inside their Group component
- Callouts use Alert
- Empty states use Empty component
- Toast notifications use sonner
- 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:
<SelectContent>
<SelectItem value="apple">Apple</SelectItem>
<SelectItem value="banana">Banana</SelectItem>
</SelectContent>Correct:
<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 |
---
Callouts use Alert
<Alert>
<AlertTitle>Warning</AlertTitle>
<AlertDescription>Something needs attention.</AlertDescription>
</Alert>---
Empty states use Empty component
<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 use sonner
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.
<DialogContent>
<DialogHeader>
<DialogTitle>Edit Profile</DialogTitle>
<DialogDescription>Update your profile.</DialogDescription>
</DialogHeader>
...
</DialogContent>---
Card structure
Use full composition — don't dump everything into CardContent:
<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:
<Button disabled>
<Spinner data-icon="inline-start" />
Saving...
</Button>---
TabsTrigger must be inside TabsList
Never render TabsTrigger directly inside Tabs — always wrap in TabsList:
<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:
<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"> |
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-*:
<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) orCheckbox(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:
<InputGroup>
<Input placeholder="Search..." />
</InputGroup>Correct:
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:
<div className="relative">
<Input placeholder="Search..." className="pr-10" />
<Button className="absolute right-0 top-0" size="icon">
<SearchIcon />
</Button>
</div>Correct:
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:
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:
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:
<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:defaultValueandtype/multipleprops differ between base and radix. See base-vs-radix.md.
---
FieldSet + FieldLegend for grouping related fields
Use FieldSet + FieldLegend for related checkboxes, radios, or switches — not div with a heading:
<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.
// 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.
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:
<Button>
<SearchIcon className="mr-2 size-4" />
Search
</Button>Correct:
<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:
<Button>
<SearchIcon className="size-4" data-icon="inline-start" />
Search
</Button>
<DropdownMenuItem>
<SettingsIcon className="mr-2 size-4" />
Settings
</DropdownMenuItem>Correct:
<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:
const iconMap = {
check: CheckIcon,
alert: AlertIcon,
}
function StatusBadge({ icon }: { icon: string }) {
const Icon = iconMap[icon]
return <Icon />
}
<StatusBadge icon="check" />Correct:
// 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} />Styling & Customization
See 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
---
Semantic colors
Incorrect:
<div className="bg-blue-500 text-white">
<p className="text-gray-600">Secondary text</p>
</div>Correct:
<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:
<span className="text-emerald-600">+20.1%</span>
<span className="text-green-500">Active</span>
<span className="text-red-600">-3.2%</span>Correct:
<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).
---
Built-in variants first
Incorrect:
<Button className="border border-input bg-transparent hover:bg-accent">
Click me
</Button>Correct:
<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:
<Card className="bg-blue-100 text-blue-900 font-bold">
<CardContent>Dashboard</CardContent>
</Card>Correct:
<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).
---
No space-x- / space-y-
Use gap-* instead. space-y-4 → flex flex-col gap-4. space-x-2 → flex gap-2.
<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:
<div className={`flex items-center ${isActive ? "bg-primary text-primary-foreground" : "bg-muted"}`}>Correct:
import { cn } from "@/lib/utils"
<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].
Related skills
How it compares
Use shadcn for copy-in React primitives with Tailwind; use design-system skills when extracting tokens from existing custom CSS codebases.
FAQ
Which CLI commands does the shadcn skill use?
shadcn runs npx shadcn@latest, pnpm dlx shadcn@latest, or bunx --bun shadcn@latest based on the project packageManager, reading components.json and info --json for context.
How does shadcn avoid custom UI reinvention?
shadcn instructs agents to run npx shadcn@latest search across registries first, then compose existing primitives like Tabs, Card, and Sidebar before writing bespoke components.
What styling rules does shadcn enforce?
shadcn requires semantic Tailwind tokens, cn() for conditional classes, flex gap instead of space-x/y, size-* for equal dimensions, and no manual z-index on overlay components.