The SSE helpers do not prescribe how identifiers are generated. Downstream services may use:
- UUIDs for globally unique identifiers across distributed systems.
- Monotonic counters or sequence numbers for ordered event streams.
- Composite keys encoding timestamp, partition, or offset information.
- Any other scheme that produces string values free of CR, LF, and NULL.
The EventId type validates the wire safety of the identifier, not its format
or generation strategy.