Install Prometheus MCP Server in Gemini CLI

What you need first

• Gemini CLI, installed.
• Docker, which gives the docker command the server starts with.
• Your own value for YOUR_PROMETHEUS_URL.

Steps

1. Open ~/.gemini/settings.json, or create it. For one project only, use .gemini/settings.json in that project.
2. Add this block. If the file already has mcpServers, add only the entry inside it.

{
  "mcpServers": {
    "prometheus-mcp-server": {
      "command": "docker",
      "args": ["run", "-i", "--rm", "-e", "PROMETHEUS_URL", "ghcr.io/pab1it0/prometheus-mcp-server:1.6.2"],
      "env": { "PROMETHEUS_URL": "YOUR_PROMETHEUS_URL" }
    }
  }
}

3. Replace YOUR_PROMETHEUS_URL with your own value.
4. Save the file and restart Gemini CLI.

Check it worked

Ask Gemini CLI: List the tools of prometheus-mcp-server.

If it does not start

Cannot connect to the Docker daemon

Docker is not running. Start it, then restart Gemini CLI.

The server starts, but its tools fail

A YOUR_… placeholder is still in the config, or its value is wrong.

Nothing changes after a restart

The file is not valid JSON any more. Look for a missing comma where the block was added.