SkillSpector

SkillSpector checks AI agent skills before you install them. Skills are instructions and scripts that Claude Code, Codex and friends run with your permissions, usually grabbed from strangers unread. Point it at a Git repo, URL, zip or folder and you get a 0-100 risk score with a SAFE, CAUTION or DO NOT INSTALL call. Free under Apache 2.0, from NVIDIA.

Install with uv tool install from the repo or build the included Dockerfile. Checks span 17 categories, from prompt injection and data exfiltration to supply-chain tricks, YARA malware signatures and MCP tool poisoning. Output comes as terminal, JSON, Markdown or SARIF, and an MCP server mode lets your agent scan before it installs.

No paid tier. Solo, small and large teams: free, and worth wiring into CI. Know this first: the LLM review stage is on by default and sends skill file contents to your provider, NVIDIA's build.nvidia.com unless you change it. Ollama or --no-llm keeps file contents local.

The catch: a CAUTION score still exits 0, so a default CI gate passes anything scoring up to 50. Add --fail-on-findings. And it never runs the skill, so a clean scan means nothing known turned up, not that it's safe.