observability

name

observability

description

OpenTelemetry tracing rules for CoreBankDemo: ActivitySource registration, span creation, and trace context propagation. **When to use:** - When adding or reviewing tracing, ActivitySource, or span logic in CoreBankDemo. - When ensuring trace context propagation and distributed tracing best practices are followed. **When NOT to use:** - Do NOT use for tracing unrelated to CoreBankDemo or for non-OpenTelemetry tracing systems. - Do NOT use for runtime log inspection or debugging—use the aspire-mcp skill for those tasks.

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Register ActivitySource

Add every new ActivitySource name when calling AddServiceDefaults:

builder.AddServiceDefaults(serviceName, new[] { nameof(MyProcessor), ... });

Custom spans

using var activity = _activitySource.StartActivity("OperationName");
activity?.SetTag("key", value);

Trace context propagation

Persist TraceParent and TraceState on outbox/inbox rows when the message is created. Restore them when processing begins to re-attach to the originating trace.

Never swallow or break the trace chain — every background processor must propagate context to its children.

Key file

CoreBankDemo.ServiceDefaults/Extensions.cs — AddServiceDefaults, OTEL pipeline configuration.