Skeleton
Freev1.0.0Loading placeholders that keep the layout steady, then reveal content in order.
Build for your project
Code/install build
Usage
Import it and pass your content. The props that matter most are listed next.
Example
"use client";
import { SkeletonRoot, SkeletonSlot } from "@/components/ui/notchset/skeleton";
export function RunSummary({ run }: { run?: { id: string; agent: string } }) {
return (
<SkeletonRoot loading={!run}>
<SkeletonSlot height={20} bar={12} width="58%">
{run?.id}
</SkeletonSlot>
<SkeletonSlot height={16} bar={10} width="32%">
{run?.agent}
</SkeletonSlot>
</SkeletonRoot>
);
}Props
SkeletonRoot loading–booleanBlocks and the sweep while true; reveal when false.
SkeletonRoot sweep / stagger–boolean / msThe sweep line (default on); the reveal step (60ms).
SkeletonSlot height / bar–numberThe slot's height, and its block's (thinner, centred).
SkeletonSlot width / round–string | number / booleanThe block's width (mirror the content); a circle.
Skeleton–divshadcn's plain block.
Anatomy
- No primitive needed: one file serves both builds.
- Content and block share a fixed-height slot, so nothing moves.
- Skeleton alone is shadcn's block, for drop-in use.
SkeletonRootdata-slot="skeleton-root"The loading card.
SkeletonSlotdata-slot="skeleton-slot"One slot.
Skeletondata-slot="skeleton"A plain block.
Source
components/ui/notchset/skeleton.tsx
Loading the code
Build for your project
Code/install build
Installation
Base UI
pnpm dlx shadcn@latest add https://notchset.dev/r/skeleton.jsonRadix
pnpm dlx shadcn@latest add https://notchset.dev/r/radix-nova/skeleton.jsonFree, no account or key. Use the command for your project's primitives: a radix-*, new-york or default style in components.json is Radix, a base-* style is Base UI. With the @notchset registry added, @notchset/<name> picks for you.
Install by hand
- 1. No extra packages: React and Tailwind CSS v4 are enough.
- 2. Copy the files to these paths (the source, or save them all as a .zip)
- components/ui/notchset/skeleton.tsx
- lib/beautiful-ui/notchset/instrument.tsx
- lib/beautiful-ui/notchset/root.ts
- 3. No stylesheet needed.
- 4. Install what it builds on first: shadcn's cn helper (lib/utils.ts, from npx shadcn init), the theme foundation (its tokens and base styles)
Styles didn't apply?
The CLI adds the styles to the CSS file named in components.json (tailwind.css). Check that it points at your global stylesheet, that the project uses Tailwind CSS v4, and that the file is imported in your root layout. Installed by hand: paste styles.css into that file.
For coding agents
Give your coding assistant the Markdown guide instead of screenshots.
Use it for
- A card or row whose data arrives after it renders
Use something else when
- Work with a known length: use Progress
- Under 300ms: show nothing
Mistakes to avoid
- Keep the real content mounted (zeros for numbers) so they roll up when revealed
Agents find it by
- skeleton, loading state, placeholder, shimmer alternative, content loading, shadcn skeleton, Notchset
Where agents read it
- Guide for this component: https://notchset.dev/md/skeleton.md
- Every component, for tools without MCP: /llms.txt
- MCP server:
https://notchset.dev/api/mcp(setup)
Behaviour
Keyboard
- —
- Not focusable: it reports state; your controls take focus
Accessibility
- The root is aria-busy while loading; hidden content is aria-hidden until revealed
- No motion is needed to read it: under reduced motion it swaps at once and the sweep is hidden
Motion
- Loading
- One 1px sweep line with a 7px head crosses the card, 1500ms, looping
- Reveal
- Each slot draws in left to right (clip-path, 460ms, k × 60ms); its block fades 140ms later (240ms)
- Reload
- Content hides at once; blocks fade back in (k × 30ms)
Responsive
- Slots fill their containers; block widths are percentages.
Performance
- CSS transitions only; slots are numbered once per render.
Changelog
v1.0.0 · 2026-10-02
First release
