> For the complete documentation index, see [llms.txt](https://vayl.gitbook.io/vayl-docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://vayl.gitbook.io/vayl-docs/api-reference/metrics.md).

# Metrics

Prometheus counters for tool calls, errors, latency and reconciliation actions.

## Prometheus metrics

> Counters in Prometheus text format. Contains no memory content, but reveals usage volume and\
> the number of active principals: keep it on an internal network, or set \`VAYL\_METRICS\_TOKEN\`\
> to require that bearer token (compared in constant time).\
> \
> Metrics: \`vayl\_tool\_calls\_total{tool}\`, \`vayl\_tool\_errors\_total{tool}\`,\
> \`vayl\_tool\_latency\_avg\_ms{tool}\`, \`vayl\_action\_total{action}\`, \`vayl\_principals\_active\`,\
> \`vayl\_license\_edition\_info{edition}\`.<br>

```json
{"openapi":"3.1.0","info":{"title":"Vayl HTTP API","version":"0.7.0"},"tags":[{"name":"Monitoring","description":"Prometheus metrics."}],"servers":[{"url":"http://127.0.0.1:8080","description":"Default bind address (VAYL_HOST / VAYL_PORT). Put TLS in front for anything but local use."}],"security":[{},{"metricsToken":[]}],"components":{"securitySchemes":{"metricsToken":{"type":"http","scheme":"bearer","description":"The value of `VAYL_METRICS_TOKEN`, when set."}}},"paths":{"/metrics":{"get":{"tags":["Monitoring"],"operationId":"metrics","summary":"Prometheus metrics","description":"Counters in Prometheus text format. Contains no memory content, but reveals usage volume and\nthe number of active principals: keep it on an internal network, or set `VAYL_METRICS_TOKEN`\nto require that bearer token (compared in constant time).\n\nMetrics: `vayl_tool_calls_total{tool}`, `vayl_tool_errors_total{tool}`,\n`vayl_tool_latency_avg_ms{tool}`, `vayl_action_total{action}`, `vayl_principals_active`,\n`vayl_license_edition_info{edition}`.\n","responses":{"200":{"description":"Metrics in Prometheus text exposition format 0.0.4.","content":{"text/plain":{"schema":{"type":"string"}}}},"401":{"description":"`VAYL_METRICS_TOKEN` is set and the request did not send it.","headers":{"WWW-Authenticate":{"schema":{"type":"string"}}},"content":{"text/plain":{"schema":{"type":"string"}}}}}}}}}
```


---

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