Open Agent Skills Format

The TypeScript toolkit for
Agent Skills

Build, validate, lint, and ship skills that work across Claude Code, GitHub Copilot, Cursor, OpenAI Codex, Gemini CLI, and 33+ more agents.

npm CI Stars License

Why Agentic Skills Framework?

The Agent Skills specification defines a portable format for giving AI agents new capabilities. It's adopted by 33+ products. This framework provides the TypeScript tooling.

Validate

Check skills against the Agent Skills specification. Catch errors before they reach production.

Lint

Go beyond spec compliance. Check context budgets, description quality, generic instructions, and progressive disclosure.

Scaffold

Generate new skills from templates. Choose from basic, with-scripts, or with-references layouts.

Get started

Install the CLI

# Install globally
npm install -g @skillscraft/cli

# Or use npx
npx @skillscraft/cli init my-skill

Use the SDK

# Install the core library
npm install @skillscraft/core

# TypeScript types
npm install @skillscraft/spec

Quick start

# Create a new skill
skill init my-skill

# Validate against the Agent Skills specification
skill validate my-skill

# Lint for best practices (context budget, description quality, etc.)
skill lint my-skill --fix

Programmatic API

import { parseSkill, validateSkill, lintSkill } from "@skillscraft/core";

// Parse a SKILL.md file
const skill = await parseSkill("./my-skill/SKILL.md");

// Validate against spec
const result = validateSkill(skill);
if (!result.valid) console.log(result.errors);

// Lint for best practices
const lint = lintSkill(skill);
lint.diagnostics.forEach(d =>
  console.log(`[${d.severity}] ${d.rule}: ${d.message}`)
);

Try it in your browser

Paste a SKILL.md below to validate and lint it. Runs entirely client-side — no data leaves your browser.

Click Validate or Lint to check the skill.

Lint rules

Best-practice checks that go beyond spec compliance.

RuleSeverityWhat it checks
context-budgetwarnSKILL.md body under 5,000 tokens / 500 lines
description-qualitywarnDescription includes "Use when" trigger clause
no-generic-instructionswarnFlags vague phrases like "handle errors appropriately"
progressive-disclosurewarnLarge skills use references/ for detail
defaults-over-menuswarnClear default tool/approach, not equal options
gotchas-presentinfoSuggests gotchas section for complex skills