15.5 Observability

Every rpc, chain step, pipeline step, actor message and saga step creates an OpenTelemetry span automatically; the traceId is passed over the network.
@trace(sample: p) sets the sampling fraction; by default the cluster's value.
Logs: log.info("…") and the levels trace debug info warn error are structured (fields from interpolation are kept separately). Metrics: metric.counter, gauge, histogram; for rpc automatically — the number of calls, errors, latencies.

See also