Using grpcurl and ZSH process substitution =()
$ grpcurl -protoset =(curl -L https://gist.github.com/sirianni/d8379a2c9a5768acb7682f138c9c55af/raw/opentelemetry.fdset) list
opentelemetry.proto.collector.logs.v1.LogsService
opentelemetry.proto.collector.metrics.v1.MetricsService
opentelemetry.proto.collector.trace.v1.TraceService
opentelemetry.proto.metrics.experimental.MetricConfig