shadcn

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

!`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-* 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

• 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

• 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
• 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

• 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() from sonner.
• 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

• 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.

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

Init/add/build/search invocations, presets, monorepo + namespaced-registry flows: PATTERNS.md.

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	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 + Component Docs

components.json / registry item fields and where to find per-component docs + examples: REGISTRY-FIELDS.md.

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, 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 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.

Updating + Quick Reference

Update/diff flows and the full CLI flag reference: CLI-REFERENCE.md.

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
• customization.md — Theming, CSS variables, extending components