MCPX Metrics
The MCPX server exposes detailed Prometheus metrics about tool calls available at: http://localhost:3000/metrics
tool_call_duration_ms Histogram
This is a Prometheus histogram that tracks the duration of each tool call in milliseconds.
Labels
Each metric entry may include one or more labels for filtering and aggregation. Labels are included only if non-empty.
| Label | Description |
|---|---|
tool-name | Name of the tool being called |
error | "true" if the call failed, "false" if successful |
agent | Name of the calling agent or service |
llm (optional) | LLM provider name (if available) |
model (optional) | Model ID used for the request (if available) |
consumer-tag (optional) | The consumer tag for the request (if provided) |
Example Output
tool_call_duration_ms_bucket{le=“50”,tool-name=“maps_directions”,error=“false”,agent=“mcpx”} 2
tool_call_duration_ms_count{tool-name=“maps_directions”,error=“false”,agent=“mcpx”} 2
tool_call_duration_ms_sum{tool-name=“maps_directions”,error=“false”,agent=“mcpx”} 67`