extract-design-system — Extract Design Tokens from Any Website
Reverse-engineer design tokens (colors, typography, spacing, border radius, shadows) from any public website and generate starter JSON and CSS custom properties for your local project. Available as an AI agent skill (Claude, Cursor, Codex) and standalone CLI.
Skills follow Anthropic's Agent Skills overview and are installable through the skills.sh ecosystem.
This repository is skills-first. It publishes an installable extract-design-system skill, and the bundled CLI is the executable workflow the agent runs under the hood.
What It Extracts
| Token category | Examples |
|---|
| Colors | brand palette, backgrounds, text, borders |
| Typography | font families, sizes, weights, line heights |
| Spacing | padding and margin scale |
| Border radius | button, card, and pill radii |
| Shadows | box-shadow values across elevation levels |
Outputs a W3C-compatible tokens.json and a tokens.css file of CSS custom properties, ready to drop into any project.
Quick Start
Install the skill:
npx skills add arvindrk/extract-design-system
Run it from a supported coding agent with a public website:
Extract the design system from https://stripe.com and generate starter token files for this project.
Expected starter outputs:
.extract-design-system/raw.json.extract-design-system/normalized.jsondesign-system/tokens.jsondesign-system/tokens.css
About This Repository
This repository contains a focused agent skill for reverse-engineering a starter design system from a public website.
The skill is designed to give coding agents a repeatable workflow for:
- analyzing a public website's colors, typography, spacing, radius, and shadows
- normalizing the extracted output into a stable structure
- generating project-local starter token files
- summarizing findings before broader styling or app changes
Available Skill
extract-design-system
Extract a starter design system from a public website and turn it into local token files.
Use when:
- You want an agent to analyze a public website's visual primitives
- You want starter design tokens for an existing project
- You want a repeatable workflow instead of ad hoc prompting
- You want the agent to summarize findings before applying broader changes
What it produces:
.extract-design-system/raw.json.extract-design-system/normalized.jsondesign-system/tokens.jsondesign-system/tokens.css
Installation
Install the skill from GitHub with the skills CLI:
npx skills add arvindrk/extract-design-system
You can also browse the skill on skills.sh.
Usage
Once installed, the skill is available to supported coding agents. The agent should use it when a request matches the extraction workflow.
Example prompts:
Extract the design system from https://stripe.com and generate starter token files for this project.
Analyze https://linear.app and summarize the design primitives before generating local tokens.
Extract colors, typography, spacing, and radius tokens from https://vercel.com and save them for this codebase.
Review https://tailwindcss.com, extract the most likely design primitives, and generate starter token files only if the results look usable.
How The Skill Works
The skill is designed to:
- confirm that the target site is public and reachable
- set expectations about scope and limitations
- run the extraction workflow through the bundled CLI
- summarize what was found in the normalized output
- generate starter token files for the current project
- ask before modifying existing app code, styles, or configuration
Scope And Limitations
- Public websites only
- Single-page extraction workflow
- Starter tokens, not a full component library
- No framework config patching or automatic app rewrites
- Dynamic, protected, or highly script-driven sites may yield incomplete output
- Extraction is useful for initialization, not pixel-perfect reproduction
Security Considerations
- Target websites are untrusted third-party input and may influence extracted output
- Generated tokens should be reviewed before being treated as authoritative design decisions
- The skill is intended for extraction and starter token generation, not automatic broad app rewrites
- Use only with public websites that you are comfortable fetching and analyzing at runtime
- Ask for confirmation before applying extracted output to existing app code, styles, or configuration
Repository Structure
This repository currently exposes:
skills/extract-design-system/SKILL.md - Main skill instructionsskills/extract-design-system/references/ - Supporting workflow and output referencessrc/ - Bundled CLI implementation used by the skilltests/ - CLI and normalization test coverage
MCP Server
The package also ships an MCP server (extract-design-system-mcp) that exposes the same workflow as structured tool calls for Cursor, Claude Desktop, and any MCP-compatible agent.
Tools
| Tool | Description |
|---|
extract_design_system | Run a full extraction from a URL and write design-system/tokens.json + tokens.css |
init_design_system | Re-emit token files from the cached .extract-design-system/normalized.json without re-fetching |
get_tokens | Read and return the current design-system/tokens.json without re-extracting |
Cursor (project-local)
Create .cursor/mcp.json in your project root:
{
"mcpServers": {
"extract-design-system": {
"command": "npx",
"args": ["-y", "extract-design-system-mcp"]
}
}
}
Restart Cursor. The server appears under Settings → Features → MCP with all 3 tools listed.
Claude Desktop
Add to ~/Library/Application Support/Claude/claude_desktop_config.json:
{
"mcpServers": {
"extract-design-system": {
"command": "npx",
"args": ["-y", "extract-design-system-mcp"],
"cwd": "/path/to/your/project"
}
}
}
Claude Desktop does not infer a working directory from context, so cwd is required. It controls where design-system/tokens.json and .extract-design-system/ are written.
Local Development
The skill's executable workflow is backed by the published npm CLI in this repository.
npm install
npx playwright install chromium
npm run typecheck
npm test
npm run build
npm run dev -- --help
npm run cli -- --help
Useful local commands:
npm run dev -- https://example.com
npm run dev -- https://example.com --extract-only
npm run cli -- https://example.com
npm run cli -- init
Community And Support
Notes
- Node.js 20+ is required
- If extraction fails because Chromium is missing, run
npx playwright install chromium
- Extraction quality depends on the target site's DOM and CSS exposure
License
MIT
