ensemblr: Skill for Claude Code

.agents/skills/shadcn/SKILL.md

shadcn is a skill for Claude Code, Codex from ensemblr-hq/ensemblr. It costs 90 tokens per session (4,591 once invoked), scanned A, a copy of shadcn, Apache-2.0.

A guide for adding, searching, fixing, styling, and composing shadcn/ui components, which are reusable interface building blocks added as project source code.

In plain words
What is it for?
Use it in shadcn/ui projects or projects with a components.json file to find components, check documentation, apply variants, and compose interfaces such as dashboards and settings pages.
Why use it?
It helps developers reuse existing components and follow the project's component, styling, and package-manager conventions.

Skill for Claude CodeCodex

Written for Claude Code and Codex: allowed-tools in frontmatter, but also agents/openai.yaml present. Also seen: installed under .agents/ (shared by several agents).

This is ensemblr-hq/ensemblr's own configuration. It tells Claude Code and Codex how to work on ensemblr itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything ensemblr configures →

Reuse

Borrowing it

Nothing to install: this file belongs to ensemblr-hq/ensemblr. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/ensemblr-hq/ensemblr/master/.agents/skills/shadcn/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/ensemblr-hq/ensemblr

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.

agentmods badge for shadcn

README.md
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Your own site
<a href="https://agentmods.dev/skills/ensemblr-hq/ensemblr/shadcn"><img src="https://agentmods.dev/badge/skills/ensemblr-hq/ensemblr/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.

agentmods 80×15 button for shadcn

Your own site · 80×15
<a href="https://agentmods.dev/skills/ensemblr-hq/ensemblr/shadcn"><img src="https://agentmods.dev/badge/skills/ensemblr-hq/ensemblr/shadcn.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 90 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,591 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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00090 $0.04591
Opus 5 $0.00045 $0.02295
Sonnet 5 $0.00018 $0.00918
Haiku 4.5 $0.00009 $0.00459

Measured 10d ago against content hash f77b41ea46a9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, 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.

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 — 18 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 · 266 lines

How it starts

The opening of the file, as written. The whole thing — 266 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

  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

Read the full file on GitHub · 266 lines

Files

What ships with it

13 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.

  1. 10d ago First seen · 266 lines · 90 tokens per session scan A f77b41ea46a9

Subscribe to this mod's changes

shadcn is a skill published in the GitHub repository ensemblr-hq/ensemblr (8 stars, last pushed today), licensed Apache-2.0. It adds 90 tokens to every session and 4,591 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. It is 94% identical to shadcn, differing in 18 lines, and is treated as a copy.

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