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.
npx agentmods add skills/vercel-labs/ds-skill-extraction-workshop/primer-reactnpx skills add vercel-labs/ds-skill-extraction-workshop --skill primer-reactgit clone --depth 1 https://github.com/vercel-labs/ds-skill-extraction-workshopWrote 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.
[](https://agentmods.dev/skills/vercel-labs/ds-skill-extraction-workshop/primer-react)<a href="https://agentmods.dev/skills/vercel-labs/ds-skill-extraction-workshop/primer-react"><img src="https://agentmods.dev/badge/skills/vercel-labs/ds-skill-extraction-workshop/primer-react.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00167 | $0.03774 |
| Opus 5 | $0.00084 | $0.01887 |
| Sonnet 5 | $0.00033 | $0.00755 |
| Haiku 4.5 | $0.00017 | $0.00377 |
Grade A, and why
primer-react 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 4d 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.
How it starts
The opening of the file, as written. The whole thing — 194 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mission
A primer-react skill is an adapter that teaches an agent how to build high-fidelity apps with Primer React. It is not a copy of the documentation. It tells the agent what to read, what APIs are public, what sources are authoritative, and how to verify that generated UI uses the system correctly.
In scope: tokens, assets, component descriptions, component APIs. Out of scope: tone of voice, marketing copy, product copywriting. When you encounter a copy/naming/casing rule during generation (e.g. "Title Case the label", "placeholder is action-oriented"), recognize it, route it — mention it as a candidate for a sibling copy skill — but do NOT extract it into this DS skill.
Setup
Install:
npm install @primer/react @primer/primitives @primer/octicons-react
Wire the provider in app/layout.tsx (verbatim from vercel-labs/primer-nextjs-template@app/layout.tsx):
"use client";
import "./globals.css";
import { BaseStyles, ThemeProvider } from "@primer/react";
import type { ReactNode } from "react";
export default function RootLayout({ children }: { children: ReactNode }) {
return (
<html
lang="en"
data-color-mode="auto"
data-light-theme="light"
data-dark-theme="dark"
suppressHydrationWarning
>
<body>
<ThemeProvider colorMode="auto">
<BaseStyles
style={{
backgroundColor: "var(--bgColor-default)",
height: "100vh",
}}
>
{children}
</BaseStyles>
</ThemeProvider>
</body>
</html>
);
}
Source: vercel-labs/primer-nextjs-template@app/layout.tsx.
"use client" is required because ThemeProvider colorMode="auto" reads the browser preference at runtime. suppressHydrationWarning on <html> is required because the provider writes the resolved mode attribute during hydration.
NOTE — the height: "100vh" on <BaseStyles style> above is verbatim from the reference project (a single-screen showcase). In YOUR app use minHeight instead; see the fixed-viewport-height Hard Rule below.
What ships with it
36 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.
- AGENTS.md 5.0 KB
- references/anti-patterns.md 4.8 KB
- references/components/branch-name.md 3.1 KB
- references/components/button.md 4.9 KB
- references/components/checkbox.md 4.5 KB
- references/components/counter-label.md 2.4 KB
- references/components/flash.md 2.5 KB
- references/components/form-control.md 6.4 KB
- references/components/heading.md 2.6 KB
- references/components/icon-button.md 4.4 KB
- references/components/label.md 3.4 KB
- references/components/progress-bar.md 7.0 KB
- references/components/relative-time.md 7.7 KB
- references/components/select.md 6.8 KB
- references/components/spinner.md 5.4 KB
- references/components/stack.md 4.8 KB
- references/components/state-label.md 4.0 KB
- references/components/text-input.md 5.4 KB
- references/components/text.md 2.5 KB
- references/components/textarea.md 3.7 KB
- references/components/timeline.md 7.2 KB
- references/design-craft.md 8.3 KB
- references/examples/dashboard.md 7.5 KB
- references/examples/empty.md 2.3 KB
- references/examples/home.md 4.8 KB
- references/examples/index.md 1.3 KB
- references/examples/new.md 5.6 KB
- references/examples/repos.md 7.2 KB
- references/examples/settings.md 6.1 KB
- references/foundations/accessibility.md 1.2 KB
- references/foundations/home.md 780 B
- references/foundations/index.md 1.2 KB
- references/foundations/octicons.md 4.0 KB
- references/foundations/primitives.md 4.9 KB
- references/foundations/product.md 1.0 KB
- references/tokens.md 9.1 KB
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.
- 4d ago First seen · 194 lines · 0 tokens per session scan A d773d59ea322
primer-react is a skill published in the GitHub repository vercel-labs/ds-skill-extraction-workshop (11 stars, last pushed 2mo ago), licensed MIT. It adds 167 tokens to every session and 3,774 once invoked, about $0.0008 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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