domains / design / shadcn-ui-component-guidance / shadcn

shadcn

Skill card

combined

The two copies address different layers of the same skill. The bergside copy is a design-system authoring guide: it defines visual foundations (typography, color tokens, spacing), accessibility tone, and a workflow for writing design-system documentation. The sickn33 copy is an implementation/CLI guide: it covers the shadcn CLI, project context, component composition rules, Tailwind styling constraints, form patterns, and icon usage. Neither copy contains the other's material steps, and crowning one would hide a real alternative. They overlap only in the general goal of producing consistent shadcn/ui output.

Repositories

Other copies

Combined skill

# shadcn/ui Skill

## Purpose
Provide both design-system guidance and implementation-ready component patterns for shadcn/ui projects.

## When to Use
- Adding new components from shadcn/ui or community registries.
- Styling, composing, or debugging existing shadcn/ui components.
- Initializing a new project or switching design system presets.
- Authoring or reviewing design-system documentation for a shadcn/ui-based product.

## CLI and Project Context
- 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`.
- Retrieve project config and installed components with `npx shadcn@latest info --json`.
- Get component documentation with `npx shadcn@latest docs <component>`.
- Search registries before writing custom UI: `npx shadcn@latest search`.
- Never decode or fetch preset codes manually; pass them directly to `npx shadcn@latest init --preset <code>`.

## Design Foundations
- Visual style: minimal, clean.
- Typography: use the project's configured font stack (commonly Geist for primary/display, Fira Code for mono) and a consistent type scale.
- Color: use semantic tokens (`bg-primary`, `text-muted-foreground`, `bg-background`) rather than raw hex or Tailwind color values.
- Spacing: follow a consistent spacing rhythm (e.g., 4/8/12/16/24/32) and avoid inconsistent gaps.
- Accessibility: target WCAG 2.2 AA, keyboard-first interactions, and visible focus states.

## Implementation Rules

### Styling and Tailwind
- Use `className` for layout, not for overriding component colors or typography.
- Do not use `space-x-*` or `space-y-*`; use `flex` with `gap-*`.
- Use `size-*` when width and height are equal.
- Use `truncate` shorthand instead of `overflow-hidden text-ellipsis whitespace-nowrap`.
- Do not use manual `dark:` color overrides; use semantic tokens.
- Use `cn()` for conditional classes.
- Do not set manual `z-index` on overlay components (Dialog, Sheet, Popover, etc.).

### Forms and Inputs
- Use `FieldGroup` + `Field` for form layout; never raw `div` with `space-y-*` or `grid gap-*`.
- Use `InputGroupInput`/`InputGroupTextarea` inside `InputGroup`; never raw `Input`/`Textarea`.
- Use `InputGroup` + `InputGroupAddon` for buttons inside inputs.
- Use `ToggleGroup` for option sets of 2–7 choices.
- Use `FieldSet` + `FieldLegend` for grouping related checkboxes/radios.
- Field validation: `data-invalid` on `Field`, `aria-invalid` on the control. For disabled: `data-disabled` on `Field`, `disabled` on the control.

### Component Composition
- Items must be inside their Group: `SelectItem` → `SelectGroup`, `DropdownMenuItem` → `DropdownMenuGroup`, `CommandItem` → `CommandGroup`.
- Use `asChild` (radix) or `render` (base) for custom triggers; check the `base` field from `npx shadcn@latest info`.
- Dialog, Sheet, and Drawer always need a Title (`DialogTitle`, `SheetTitle`, `DrawerTitle`); use `className="sr-only"` if visually hidden.
- Use full Card composition: `CardHeader`/`CardTitle`/`CardDescription`/`CardContent`/`CardFooter`.
- Button has no `isPending`/`isLoading`; compose with `Spinner` + `data-icon` + `disabled`.
- `TabsTrigger` must be inside `TabsList`.
- `Avatar` always needs `AvatarFallback`.

### Use Components, Not Custom Markup
- Check if a component exists before writing a styled `div`.
- Callouts use `Alert`; empty states use `Empty`; toasts via `sonner` (`toast()`).
- 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 in `Button` use `data-icon="inline-start"` or `data-icon="inline-end"`.
- Do not add sizing classes to icons inside components; components handle icon sizing via CSS.
- Pass icons as objects, not string keys.

## Design-System Authoring Workflow
When generating design-system guidance for a shadcn/ui project:
1. Restate the design intent in one sentence before proposing rules.
2. Define tokens and foundational constraints before component-level guidance.
3. Specify component anatomy, states, variants, and interaction behavior.
4. Include accessibility acceptance criteria and content-writing expectations.
5. Add anti-patterns and migration notes for existing inconsistent UI.
6. End with a QA checklist that can be executed in code review.

## Required Output Structure for Design-System Docs
- Context and goals
- Design tokens and foundations
- Component-level rules (anatomy, variants, states, responsive behavior)
- Accessibility requirements and testable acceptance criteria
- Content and tone standards with examples
- Anti-patterns and prohibited implementations
- QA checklist

## Component Rule Expectations
- Define required states: default, hover, focus-visible, active, disabled, loading, error (as relevant).
- Describe interaction behavior for keyboard, pointer, and touch.
- State spacing, typography, and color-token usage explicitly.
- Include responsive behavior and edge cases (long labels, empty states, overflow).

## Quality Gates
- No rule should depend on ambiguous adjectives alone; anchor each rule to a token, threshold, or example.
- Every accessibility statement must be testable in implementation.
- Prefer system consistency over one-off local optimizations.
- Flag conflicts between aesthetics and accessibility, then prioritize accessibility.
- Use "must" for non-negotiable rules and "should" for recommendations.
- Pair every do-rule with at least one concrete don't-example.
- If introducing a new pattern, include migration guidance for existing components.

## Conflicts
- The bergside copy prescribes a fixed color palette (primary=#000000, secondary=#111111, success=#16A34A, warning=#D97706, danger=#DC2626, surface=#FFFFFF, text=#111827) and a fixed typography scale (12/14/16/20/24/32). The sickn33 copy does not prescribe a fixed palette or type scale and instead defers to the project's shadcn config and semantic tokens. When authoring design-system docs, use the project's actual tokens; when implementing components, use semantic tokens from the project config.