Event yaml definition should allow to document SeverityNumber

[lmolkova]

Area(s)

area:events

What happened?

Description

Based on the spec-ed out Event parameters, events have optional SeverityNumber

But none of the existing events document it and it's not covered in the https://github.com/open-telemetry/semantic-conventions/blob/main/docs/general/events.md

Expected Result

We have a way to define and document severity for the events.

Semantic convention version

1.24.0

Additional context

No response

[tedsuo]

@lmolkova I don't think we should associate events with a specific severity number. The severity of an event is based to the context in which the event is occurring, not intrinsic to the event itself.

For example, the same exception may be an error or a warning depending on the context. Other events may be debug, info, or warn depending on their context. Based on that, I don't think it is correct to imply there is a default or "correct" severity for events.

[MSNev]

Events SDK default for SeverityNumber
https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/logs/event-sdk.md

[lmolkova]

Discussed at semconv WG 6/17:

• some events would need severity, we can discuss it when we introduce them. They are emitted by instrumentation libraries (e.g. GenAI response content should probably be Verbose) and severity can be used as the enablement mechanism for such events
• I've moved it to tooling project since the request here is to be able to specify the severity (i.e. support it in the schema definition and anything derived from it such as codegen)