Radii Builder

Generate a custom Claude Code skill — describe what you want, get a complete .md skill file

Install in one command

Requires Claude Code. Run from your project root.

$curl -sL https://radii.cloud/skills/radii-builder.md -o .claude/skills/radii-builder.md

Then in Claude Code, type /radii-builder to activate.

About

Radii Builder is a meta-skill: a skill that generates skills. Describe in plain text what you want Claude to do — "audit my CSS for performance issues", "generate button variants for my design system", "review my Figma-to-code translation quality" — and get back a complete .md skill file you can drop into .claude/skills/ and start using immediately. The generated skill follows Radii's format: a clear system prompt, specific measurable rules, a fill-in-the-blank output template, and reference links. Build a library of custom skills tuned to your exact codebase, design system, and team standards.

What it does

Takes a plain-language description and generates a complete Claude Code skill file in Radii format
Guides the skill type: analysis (audit), generation (create), review (checklist), or vocabulary (translate)
Extracts specific, measurable rules — not vague guidelines but exact values, flags, and code patterns
Designs a fill-in-the-blank output template so every invocation produces consistent, structured output
Outputs an installation block: mkdir + file path so you can start using the skill immediately
Works for any domain: CSS performance, design system compliance, Figma handoff quality, copywriting review, API consistency, and more

Give it

1.A plain-language description: "I want a skill that audits my CSS for performance issues"
2.Optional: examples of what good and bad output looks like
3.Optional: specific rules or values your team uses

Example output

Input: "I want a skill that reviews my CSS for performance issues"

Output: A complete .md file with:
- System prompt: "You are a CSS performance auditor..."
- Rules: animate only transform/opacity, flag width/height animations, flag will-change: all, check filter/backdrop-filter usage
- Output format: violations list with severity + CSS fix per violation
- Links: radii.cloud/terms/animation, radii.cloud/terms/transition

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To install:
mkdir -p .claude/skills
# Save the generated file to: .claude/skills/css-perf.md