Cijo Thomas

https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/supplementary-guidelines.md can be a good place to call out any warnings .

Sorry for the delay. I'll review soon.

> Exporter doesn't validate; Logs SeverityNumber 1-24 mapping I am not sure if Exporter should do anything to validate..Any reason why you think exporter must do this? (In my view,...

> Summary is [legacy](https://opentelemetry.io/docs/specs/otel/metrics/data-model/#summary-legacy) and may not be required). Summary is not required. There is no way to produce them in the SDK also.

> I'm working through the points in the [compliance matrix](https://github.com/open-telemetry/opentelemetry-specification/blob/main/spec-compliance-matrix.md#exporters) to reconfirm what else we need. There's a few things in here it seems like we now support. @cijothomas is...

> Concurrent Export Limits lets not worry about it for now in the OTLP Exporters, as upstream sdk (BatchProcessor) only calls export sequentially. We need to first address that issue,...

> Metric Exporter configurable default aggregation I'd treat this as very low priority, and move it outside scope for stable release. It is not something we have seen asks for....

https://github.com/open-telemetry/opentelemetry-specification/issues/4371#issuecomment-2651367885 OTel is now more restrictive than Prometheus, so would be good to relax some of the restrictions.

> Although I can see that this works, it feels like a big leak of impl details into the user's domain. What would it look like as a helper in...

> My other question is - do we impact any of our users by requiring a separate tokio runtime in this case, for instance, folks in resource-constrained environments? Quite valid...