skillcheck: A linter for SKILL.md files that catches cross-agent compatibility issues
What skillcheck does
skillcheck is a linter for SKILL.md files that validates against the agentskills.io specification. It was created after encountering issues where skills written for Claude Code wouldn't load in VS Code due to mismatched name fields and other cross-agent compatibility problems.
Key features
- Scores description quality from 0-100 for discoverability (agents use this field to decide whether to activate a skill)
- Warns about fields that only work in Claude Code and won't work in VS Code, Codex, or Cursor
- Checks that file references in the SKILL.md body point to files that exist on disk
- Validates progressive disclosure token budgets from the spec
- Provides JSON output and exit codes for CI integration
- Includes a GitHub Action
Installation and usage
Install via pip: pip install skillcheck
Run it by pointing at a file or directory: skillcheck path/to/skill.md or skillcheck path/to/skills/directory
Technical details
- Built with Python 3.10+
- Only one dependency: PyYAML
- MIT licensed
- Built with assistance from Claude and VS Code
Comparison with existing tools
The creator read the source code of every existing validator before building skillcheck, including skills-ref, cclint, skills-cli, and Anthropic's quick_validate.py. The description scoring, cross-agent warnings, and file reference checks don't exist in any of these existing tools. Some frontmatter validation overlaps with existing validators.
📖 Read the full source: r/ClaudeAI
👀 See Also
MCP Server Indexes Codebases into Knowledge Graph for 10x Token Reduction
A new MCP server called codebase-memory-mcp parses codebases into a persistent knowledge graph using tree-sitter, reducing token usage by at least 10x for structural queries. Benchmarked across 35 real-world repositories, it replaces file-by-file exploration with graph queries.
Lumyr: Dashboard Generation via Claude with Python and Streamlit Automation
Lumyr is a tool that generates live, shareable dashboards from plain English descriptions using Claude for dashboard generation and automating the Python and Streamlit layer. Users don't need to write Python, open Streamlit, deploy, set up hosting, or manage infrastructure.
Claude Code Plugin Yoink Replaces Library Dependencies to Reduce Supply Chain Risk
Yoink is a Claude Code plugin that removes complex dependencies by reimplementing only needed functions, using a three-step workflow with /setup, /curate-tests, and /decompose commands. It currently supports Python with TypeScript and Rust support underway.
Context Gateway: An Open-Source Proxy for Compressing AI Agent Context
Context Gateway is an open-source proxy that sits between coding agents and LLMs, compressing tool outputs before they enter the context window. It uses small language models to detect signal in context, performs background compaction at 85% window capacity, and includes spending caps, a dashboard, and Slack notifications.