Claude Desktop

Claude Desktop is the reference MCP host — Anthropic ships the protocol from there. Wiring Prometheus into it takes two changes: edit claude_desktop_config.json and restart the app.

1. Open the config

In Claude Desktop, go to Settings → Developer → Edit Config. That opens the JSON file at:

• macOS — ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows — %APPDATA%\Claude\claude_desktop_config.json

If the file is empty, start from { "mcpServers": {} }.

2. Add the prometheus block

{
  "mcpServers": {
    "prometheus": {
      "command": "npx",
      "args": ["-y", "@prometheus/context-mcp@latest"],
      "env": {
        "PROMETHEUS_API_KEY": "<your-api-key>",
        "PROMETHEUS_WORKSPACE_ID": "<your-workspace-id>",
        "PROMETHEUS_WORKER_URL": "https://api.prom.codes"
      }
    }
  }
}

PROMETHEUS_WORKER_URL is optional — the package defaults to https://api.prom.codes (Vercel Edge proxy in Frankfurt). Override only if you self-host the worker or want to point at a staging instance.

3. Restart Claude Desktop

Quit completely (⌘Q on macOS, not just closing the window) and reopen. A hammer icon appears in the chat composer once the prometheus server registered. Click it to inspect available tools.

Troubleshooting

What tools become available

Once registered, Claude can call any of the six Prometheus MCP tools. See MCP tools for the full list and JSON schemas.