A guide for using shadcn/ui, a collection of interface components added as source code to a project rather than used as a separate package.

Adding, searching, fixing, styling, and composing components such as buttons, tabs, cards, forms, dashboards, and chat interfaces.

It helps find and reuse existing components, follow the project’s design system, and avoid rebuilding common interface pieces.

shadcn — Skill for Claude Code and Codex by udecode

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent

npx skills add udecode/plate-playground-template --skill shadcn

Clone the repo

git clone --depth 1 https://github.com/udecode/plate-playground-template

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

README.md

[![agentmods](https://agentmods.dev/badge/skills/udecode/plate-playground-template/shadcn/github.svg)](https://agentmods.dev/skills/udecode/plate-playground-template/shadcn)

Your own site

<a href="https://agentmods.dev/skills/udecode/plate-playground-template/shadcn"><img src="https://agentmods.dev/badge/skills/udecode/plate-playground-template/shadcn/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

Your own site · 80×15

<a href="https://agentmods.dev/skills/udecode/plate-playground-template/shadcn"><img src="https://agentmods.dev/badge/skills/udecode/plate-playground-template/shadcn.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 113 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 5,402 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

Origin 94% copy Near-identical to another mod in the catalogue.

Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

Model	Per session	Once invoked
Fable 5.1	$0.00113	$0.05402
Opus 5.5	$0.00045	$0.02161
Sonnet 5.5	$0.00023	$0.01080
Haiku 4.5	$0.00011	$0.00540

Measured 10d ago against content hash 93951e5e83f6, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

shadcn scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/showcase-coverage.mjs), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

94% identical to shadcn — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/shadcn/SKILL.md · 297 lines

How it starts

The opening of the file, as written. The whole thing — 297 lines — stays where its author put it; the contents beside it link to each section on GitHub.

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

Use existing components first. Use npx shadcn@latest search to check registries before writing custom UI. Check community registries too.
Compose, don't reinvent. Settings page = Tabs + Card + form controls. Dashboard = Sidebar + Card + Chart + Table.
Use built-in variants before custom styles. variant="outline", size="sm", etc.
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

Read the full file on GitHub · 297 lines

Files

What ships with it

20 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

10d ago Changed · +1 lines 93951e5e83f6
15d ago Changed · +18 lines · +19 tokens per session 0185f715bc98
1mo ago Changed · +2 lines deba6c5152d9
1mo ago First seen · 276 lines · 94 tokens per session scan A a45cddd4511f

Subscribe to this mod's changes

shadcn is a skill published in the GitHub repository udecode/plate-playground-template (242 stars, last pushed 2d ago), licensed MIT. It adds 113 tokens to every session and 5,402 once invoked, about $0.0005 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 94% identical to shadcn, differing in 0 lines, and is treated as a copy.

Design and UX Frontend editor nextjs plate radix-ui shadcn-ui slate

shadcn

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…

udecode/plate-template · 113 tokens

vercel-composition-patterns

React composition patterns that scale. Use when refactoring components with boolean prop proliferation, building flexible component libraries, or designing reusable APIs. Triggers on tasks involving compound components, render props, context providers, or component architecture. Includes React 19 API changes.

udecode/plate-template · 58 tokens

vercel-react-best-practices

React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing, reviewing, or refactoring React/Next.js code to ensure optimal performance patterns. Triggers on tasks involving React components, Next.js pages, data fetching, bundle optimization, or performance…

udecode/plate-template · 67 tokens

testing

Skill "testing" from udecode/plate-template, covering testing goal, core rules, seam selection, fixtures and assertions and quick reference.

udecode/plate-template · 5 tokens

shadcn

shadcn-ui/ui · 113 tokens

kiranism-shadcn-dashboard

Guide for building features, pages, tables, forms, themes, and navigation in this Next.js 16 shadcn dashboard template. Use this skill whenever the user wants to add a new page, create a feature module, build a data table, add a form, configure navigation items, add a theme, set up RBAC access control, or work with…

Kiranism/next-shadcn-dashboard-starter · 142 tokens

shadcn

Getting it into your agent

Wrote this? Show the measurements

What it costs to keep this loaded

Grade A, and why

Nothing flagged

This is a copy

How it starts

shadcn/ui

Current Project Context

Principles

Critical Rules

Styling & Tailwind → styling.md

Forms & Inputs → forms.md

What ships with it

What this file has done since we first saw it

Other skills, from other repositories

shadcn

vercel-composition-patterns

vercel-react-best-practices

testing

shadcn

kiranism-shadcn-dashboard