Why this matters
A skill is a set of instructions Claude reads and follows. An MCP server is a small program that runs on your machine or a server you control. Both can be powerful — and both run with the same access you have: your files, your shell, your API keys.
That means a poorly-written or malicious skill or server could read sensitive files, run commands, or leak credentials. This is normal supply-chain risk, the same kind you manage when adding an npm package or a browser extension. It is very manageable — you just have to be deliberate about what you trust.
Ryzo curates the directories as a convenience. We do not author, endorse, or audit the third-party repositories listed there. Treat every entry as code from a stranger until you have checked it.
Before you install — a 5-point checklist
Run through these for any third-party skill or MCP server.
- 1
Prefer official and well-known sources
Anthropic's own repositories and widely-adopted, actively-maintained projects carry far less risk than an unknown repo with a handful of stars. Popularity is not proof, but obscurity is a flag.
- 2
Read the SKILL.md / server code before installing
A skill is just instructions Claude will follow; an MCP server is a program that runs on your machine. Open the source and skim what it actually does — especially anything that reads files, makes network calls, or touches credentials.
- 3
Check what access it asks for
MCP servers often need API keys or tokens. Give them the narrowest scope that works, store secrets in a manager (not plaintext), and never paste a token into a server you have not vetted.
- 4
Pin to a specific version or commit
A repo you trusted yesterday can change tomorrow. Where the tooling allows, pin to a release or commit you have reviewed rather than tracking the latest automatically.
- 5
Watch for prompt injection
Skills and the data MCP servers return can contain hidden instructions aimed at Claude. Treat third-party content as untrusted input, and be cautious about skills that ask Claude to run shell commands or exfiltrate data.
Installing skills & plugins
Most skill repositories are distributed as Claude Code plugins via a marketplace. In Claude Code you add the marketplace, then install the plugin you want — only after reviewing its source:
/plugin marketplace add owner/repo
/plugin install plugin-name@marketplaceInstalling MCP servers
MCP servers are added with the Claude Code CLI (or in your client's config). Each server in our directory shows its own command; the general shape is:
claude mcp add name -- command-to-run-the-serverCommand syntax changes as Claude Code evolves — always confirm the exact, current commands in the official Claude Code documentation.