Where do the metric labels come from?

[WesselAtWork]

I have the Java Agent setup wired like

Agent -> Alloy OTLP -> Alloy Batch -> LGTM (Mimir, Loki, Tempo)

The http_client_request_duration_seconds_sum, http_client_request_duration_seconds_count and http_client_request_duration_seconds_bucket metrics are exported with server_address, job, http_request_method, http_response_status_code, network_protocol_version, server_port labels.

I wanted to add the http url attributes (specifically the url.path) to the exported labels and couldn't figure out how to.
I though I could just do

otelcol.processor.transform "default" {
  error_mode = "ignore"

  metric_statements {
    context = "datapoint"

    statements = [
      `set(attributes["url_path"], resource.attributes["url.path"])`,
    ]
  }

  output {
    metrics = [otelcol.processor.batch.default.input]
  }
}

But that didn't work.

I can see them in the trace under the span category, so I know it is capable of exporting them.

Also tried resource_to_telemetry_conversion = true but that just gave me a bunch of otel metadata.

Should I set something on the agent (exporter) or is this something that Alloy is doing?

[WesselAtWork]

I think it's something that should be set on the exporter side
open-telemetry/opentelemetry-java-instrumentation#11220