Counters have a suffix "_total"

[fvaleri]

The Prometheus library appends the _total type suffix to all counter metrics, which you should remove when adding these metrics to the allowlist. If you forget or don't know that you have to remove this suffix from the endpoint output, you can easily make a mistake when filtering by the exact metric name (see strimzi/strimzi-kafka-operator#12142).

Prometheus also appends unit suffix (_bytes, _ratio and _milliseconds), so the issue is not limited to the type suffix (_total). As a minimum we should document this behavior in the README, but it would be good to export the original metrics name without any change as OTel collector does (open-telemetry/opentelemetry-collector#6403).

[scholzj]

Triaged on 8.1.2026: There is not much we can do about the metric suffixes as that is part of the Prometheus spec. But we should add comments to the metric output to document that way what is the corresponding metric name to be used in the Metric Reporter configuration.