Prometheus MCP Server

Instructions

Implementation Reference

• src/prometheus_mcp_server/server.py:439-449 (registration)

  Registration of the get_metric_metadata tool using the @mcp.tool decorator, including description and UI annotations.

  @mcp.tool(
      description="Get metadata for a specific metric",
      annotations={
          "title": "Get Metric Metadata",
          "icon": "ℹ️",
          "readOnlyHint": True,
          "destructiveHint": False,
          "idempotentHint": True,
          "openWorldHint": True
      }
  )

• src/prometheus_mcp_server/server.py:450-471 (handler)

  The handler function that implements the core logic of get_metric_metadata: queries Prometheus /api/v1/metadata endpoint, handles different response structures ('metadata', 'data', or raw), converts single dict to list if needed, and returns the metadata.

  async def get_metric_metadata(metric: str) -> List[Dict[str, Any]]:
      """Get metadata about a specific metric.
  
      Args:
          metric: The name of the metric to retrieve metadata for
  
      Returns:
          List of metadata entries for the metric
      """
      logger.info("Retrieving metric metadata", metric=metric)
      endpoint = f"metadata?metric={metric}"
      data = make_prometheus_request(endpoint, params=None)
      if "metadata" in data:
          metadata = data["metadata"]
      elif "data" in data:
          metadata = data["data"]
      else:
          metadata = data
      if isinstance(metadata, dict):
          metadata = [metadata]
      logger.info("Metric metadata retrieved", metric=metric, metadata_count=len(metadata))
      return metadata