There is some very clear Go code for this: https://github.com/cosmos/ibc-go/blob/main/modules/core/04-channel/keeper/events.go

I would be happy just adding those to the spec, so it is clear for other implementations.

Or... we decide these events are not part of the spec?

Definitely the events relayers should expect need to be part of the spec. Otherwise relayers will have to implement different parsing logic for each implementation. We should standardize on the format that relayers can expect

Has there been research into how other protocols emit events?

Dont want to tie other protocols into cosmos style events, since IBC is generally agnositc.

@AdityaSripal I guess this is connected to #534, right?