skillscore
v1.2.1
Published
A CLI tool that evaluates AI agent skills and produces quality scores
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The universal quality standard for AI agent skills. Evaluate any SKILL.md — from skills.sh, ClawHub, GitHub, or your local machine.
✨ Features
- 🎯 Comprehensive Evaluation: 8 scoring categories with weighted importance
- 🎨 Multiple Output Formats: Terminal (colorful), JSON, and Markdown reports
- 🔍 Deterministic Analysis: Reliable, reproducible scoring without requiring API keys
- 📋 Detailed Feedback: Specific findings and actionable recommendations
- ⚡ Fast & Reliable: Built with TypeScript for speed and reliability
- 🌍 Cross-Platform: Works on Windows, macOS, and Linux
- 🐙 GitHub Integration: Score skills directly from GitHub repositories
- 📊 Batch Mode: Compare multiple skills with a summary table
- 🗣️ Verbose Mode: See all findings, not just truncated summaries
📦 Installation
Global Installation (Recommended)
npm install -g skillscoreLocal Installation
npm install skillscore
npx skillscore ./my-skill/From Source
git clone https://github.com/joeynyc/skillscore.git
cd skillscore
npm install
npm run build
npm link🚀 Quick Start
Evaluate a skill directory:
skillscore ./my-skill/📖 Usage Examples
Basic Usage
# Evaluate a skill
skillscore ./skills/my-skill/
# Evaluate with verbose output (shows all findings)
skillscore ./skills/my-skill/ --verboseGitHub Integration
# Full GitHub URL (always recognized)
skillscore https://github.com/vercel-labs/skills/tree/main/skills/find-skills
# GitHub shorthand (requires -g/--github flag)
skillscore -g vercel-labs/skills/find-skills
# Anthropic skills
skillscore -g anthropic/skills/skill-creatorOutput Formats
# JSON output
skillscore ./skills/my-skill/ --json
# Markdown report
skillscore ./skills/my-skill/ --markdown
# Save to file
skillscore ./skills/my-skill/ --output report.md
skillscore ./skills/my-skill/ --json --output score.jsonBatch Mode
# Compare multiple skills (auto-enters batch mode)
skillscore ./skill1 ./skill2 ./skill3
# Explicit batch mode flag
skillscore ./skill1 ./skill2 --batch
# Compare GitHub skills
skillscore -g user/repo1/skill1 user/repo2/skill2 --jsonUtility Commands
# Show version
skillscore --version
# Get help
skillscore --help📊 Example Output
Terminal Output
📊 SKILLSCORE EVALUATION REPORT
============================================================
📋 Skill: Weather Information Fetcher
Fetches current weather data for any city using OpenWeatherMap API
Path: ./weather-skill
🎯 OVERALL SCORE
A- - 92.0% (9.2/10.0 points)
📝 CATEGORY BREAKDOWN
------------------------------------------------------------
Structure ████████████████████ 100.0%
SKILL.md exists, clear name/description, follows conventions
Score: 10/10 (weight: 15%)
✓ SKILL.md file exists (+3)
✓ Clear skill name: "Weather Information Fetcher" (+2)
✓ Clear description provided (+2)
... 2 more findings
Clarity ██████████████████░░ 90.0%
Specific actionable instructions, no ambiguity, logical order
Score: 9/10 (weight: 20%)
✓ Contains specific step-by-step instructions with commands (+3)
✓ No ambiguous language detected (+3)
✓ Instructions follow logical order (+2)
... 1 more finding (use --verbose to see all)
Safety ██████████████░░░░░░ 70.0%
No destructive commands, respects permissions
Score: 7/10 (weight: 20%)
✓ No dangerous destructive commands found (+3)
✓ No obvious secret exfiltration risks (+3)
✗ Some potential security concerns detected
📈 SUMMARY
------------------------------------------------------------
✅ Strengths: Structure, Clarity, Dependencies, Documentation
❌ Areas for improvement: Safety
Generated: 2/11/2026, 3:15:49 PMBatch Mode Output
📊 BATCH SKILL EVALUATION
Evaluating 3 skill(s)...
[1/3] Processing: ./weather-skill
✅ Completed
[2/3] Processing: ./file-backup
✅ Completed
[3/3] Processing: user/repo/skill
✅ Completed
📋 COMPARISON SUMMARY
Skill Grade Score Structure Clarity Safety Status
Weather Information Fetcher A- 92.0% 100% 90% 70% OK
File Backup Tool B+ 87.0% 95% 85% 90% OK
Advanced Data Processor A 94.0% 100% 95% 85% OK
📈 BATCH SUMMARY
✅ Successful: 3
📊 Average Score: 91.0%🏆 Scoring System
SkillScore evaluates skills across 8 weighted categories:
| Category | Weight | Description | |----------|--------|-------------| | Structure | 15% | SKILL.md exists, clear name/description, file organization, artifact output spec | | Clarity | 20% | Specific actionable instructions, no ambiguity, logical order | | Safety | 20% | No destructive commands, respects permissions, network containment | | Dependencies | 10% | Lists required tools/APIs, install instructions, env vars | | Error Handling | 10% | Failure instructions, fallbacks, no silent failures | | Scope | 10% | Single responsibility, routing quality, negative examples | | Documentation | 10% | Usage examples, embedded templates, expected I/O | | Portability | 5% | Cross-platform, no hardcoded paths, relative paths |
Scoring Methodology
Each category is scored from 0-10 points based on specific criteria:
- Structure: Checks for SKILL.md existence, clear naming, proper organization, and whether outputs/artifacts are defined
- Clarity: Analyzes instruction specificity, ambiguity, logical flow
- Safety: Scans for destructive commands, security risks, permission issues, and network containment (does the skill scope network access when using HTTP/APIs?)
- Dependencies: Validates tool listings, installation instructions, environment setup
- Error Handling: Reviews error scenarios, fallback strategies, validation
- Scope: Assesses single responsibility, trigger clarity, conflict potential, negative routing examples ("don't use when..."), and routing quality (concrete signals vs vague descriptions)
- Documentation: Evaluates examples, I/O documentation, troubleshooting guides, and embedded templates/worked examples with expected output
- Portability: Checks cross-platform compatibility, path handling, limitations
v1.1.0: Production-Validated Checks
Five new sub-criteria added in v1.1.0, inspired by OpenAI's Skills + Shell + Compaction blog and production data from Glean:
| Check | Category | Points | Why It Matters | |-------|----------|--------|----------------| | Negative routing examples | Scope | 2 | Skills that say when NOT to use them trigger ~20% more accurately (Glean data) | | Routing quality | Scope | 1 | Descriptions with concrete tool names, I/O, and "use when" patterns route better than marketing copy | | Embedded templates | Documentation | 2 | Real output templates inside the skill drove the biggest quality + latency gains in production | | Network containment | Safety | 1 | Skills combining tools + open network access are a data exfiltration risk without scoping | | Artifact output spec | Structure | 1 | Skills that define where outputs go create clean review boundaries |
Grade Scale
| Grade | Score Range | Description | |-------|-------------|-------------| | A+ | 97-100% | Exceptional quality | | A | 93-96% | Excellent | | A- | 90-92% | Very good | | B+ | 87-89% | Good | | B | 83-86% | Above average | | B- | 80-82% | Satisfactory | | C+ | 77-79% | Acceptable | | C | 73-76% | Fair | | C- | 70-72% | Needs improvement | | D+ | 67-69% | Poor | | D | 65-66% | Very poor | | D- | 60-64% | Failing | | F | 0-59% | Unacceptable |
📁 What Makes a Good Skill?
Required Structure
my-skill/
├── SKILL.md # Main skill definition (REQUIRED)
├── README.md # Documentation (recommended)
├── package.json # Dependencies (if applicable)
├── scripts/ # Executable scripts
│ ├── setup.sh
│ └── main.py
└── examples/ # Usage examples
└── example.mdSKILL.md Template
# My Awesome Skill
Brief description of what this skill does and when to use it.
## When to Use
Use this skill when you need to [specific task] with [specific tools/inputs].
## When NOT to Use
Don't use this skill when:
- The task is [alternative scenario] — use [other skill] instead
- You need [different capability]
## Dependencies
- Tool 1: Installation instructions
- API Key: How to obtain and configure
- Environment: OS requirements
## Usage
1. Step-by-step instructions
2. Specific commands to run
3. Expected outputs
## Output
Results are written to `./output/` as JSON files.
## Error Handling
- Common issues and solutions
- Fallback strategies
- Validation steps
## Examples
### Example Output
```json
{
"status": "success",
"result": "Example of what the skill produces"
}# Working example
./scripts/main.py --input "test data"Limitations
- Known constraints
- Platform-specific notes
- Edge cases
## 🔧 API Usage
Use SkillScore programmatically in your Node.js projects:
```typescript
import { SkillParser, SkillScorer, TerminalReporter } from 'skillscore';
import type { Reporter, SkillScore } from 'skillscore';
const parser = new SkillParser();
const scorer = new SkillScorer();
const reporter: Reporter = new TerminalReporter();
async function evaluateSkill(skillPath: string): Promise<SkillScore> {
const skill = await parser.parseSkill(skillPath);
const score = await scorer.scoreSkill(skill);
const report = reporter.generateReport(score);
console.log(report);
return score;
}All three reporters (TerminalReporter, JsonReporter, MarkdownReporter) implement the Reporter interface.
🛠️ CLI Options
Usage: skillscore [options] <path...>
Arguments:
path Path(s) to skill directory, GitHub URL, or shorthand
Options:
-V, --version Output the version number
-j, --json Output in JSON format
-m, --markdown Output in Markdown format
-o, --output <file> Write output to file
-v, --verbose Show ALL findings (not just truncated)
-b, --batch Batch mode for comparing multiple skills
-g, --github Treat shorthand paths as GitHub repos (user/repo/path)
-h, --help Display help for command🧪 Testing
# Run all tests
npm test
# Run tests in watch mode
npm run test:ui
# Run tests once
npm run test:run
# Lint code
npm run lint
# Build project
npm run build🤝 Contributing
We welcome contributions! Here's how to get started:
Development Setup
git clone https://github.com/joeynyc/skillscore.git
cd skillscore
npm install
npm run build
npm link
# Run in development mode
npm run dev ./test-skill/
# Build for production
npm run buildRunning Tests
npm testSubmitting Changes
- Fork the repository
- Create a feature branch (
git checkout -b feature/amazing-feature) - Make your changes
- Add tests for new functionality
- Ensure all tests pass (
npm test) - Lint your code (
npm run lint) - Commit your changes (
git commit -m 'Add amazing feature') - Push to the branch (
git push origin feature/amazing-feature) - Open a Pull Request
Coding Standards
- Use TypeScript for all new code
- Follow existing code style (enforced by ESLint)
- Add tests for new features
- Update documentation for API changes
- Keep commits focused and descriptive
🐛 Troubleshooting
Common Issues
Error: "Path does not exist"
- Check for typos in the path
- Ensure you have permission to read the directory
- Verify the path points to a directory, not a file
Error: "No SKILL.md file found"
- Skills must contain a SKILL.md file
- Check if you're pointing to the right directory
- The file must be named exactly "SKILL.md"
Error: "Git is not available"
- Install Git to clone GitHub repositories
- macOS:
xcode-select --install - Ubuntu:
sudo apt-get install git - Windows: Download from git-scm.com
Scores seem too high/low
- Scoring is calibrated against real-world skills
- See the scoring methodology above
- Consider the specific criteria for each category
Getting Help
📄 License
This project is licensed under the MIT License - see the LICENSE file for details.
🙏 Acknowledgments
- Inspired by the need for quality assessment in AI agent skills
- Built for the OpenClaw and Claude Code communities
- Thanks to all contributors and skill creators
- Scoring methodology informed by software engineering best practices and OpenAI's production skill patterns
📊 Example Scores
Here are some real-world examples of how different skills score:
- Vercel find-skills: 85% (B) - Well-structured, good documentation
- Anthropic frontend-design: 87% (B+) - Excellent clarity, minor dependency issues
- Anthropic skill-creator: 92% (A-) - Outstanding overall, minor safety concerns
