Opn MCP Server

opn-mcp

An MCP server for opn.onl — the open-source, self-hostable URL shortener. It lets AI assistants (Claude Desktop, Cursor, etc.) shorten links, read analytics, generate QR codes, and manage links in natural language.

Works against the hosted service or your own self-hosted instance.

Setup

1. Get an API key

On your opn.onl instance, go to Settings → API Keys, create a key, and copy it (it starts with opn_ and is shown once).

2. Add the server to your MCP client

Claude Desktop — edit claude_desktop_config.json (~/Library/Application Support/Claude/ on macOS, %APPDATA%\Claude\ on Windows):

{
  "mcpServers": {
    "opn": {
      "command": "npx",
      "args": ["-y", "opn-mcp"],
      "env": {
        "OPN_API_KEY": "opn_your_key_here"
      }
    }
  }
}

Restart your client. That's it — it talks to the hosted API (https://l.opn.onl) by default.

Not published to npm yet? Use the GitHub source instead — same config, just swap the args: "args": ["-y", "github:ysalitrynskyi/opn-mcp"] (it builds on install).

Self-hosted instance

Point OPN_BASE_URL at your own instance's API host:

{
  "mcpServers": {
    "opn": {
      "command": "npx",
      "args": ["-y", "opn-mcp"],
      "env": {
        "OPN_API_KEY": "opn_your_key_here",
        "OPN_BASE_URL": "https://l.your-domain.com"
      }
    }
  }
}

Configuration

Tools

Example prompts

• "Shorten https://example.com/very/long/url and call it launch-2026"
• "How many clicks did link 42 get, and from which countries?"
• "Give me a branded SVG QR code for link 42"
• "List my last 10 links"

Development

npm install
npm run build      # tsc → dist/
npm test           # vitest
OPN_API_KEY=opn_… npm run dev   # run from source (stdio)

License

MIT © ysalitrynskyi. Part of the opn.onl project.