I'm not too familiar with it. it's more about the schema of your business logic messages, rather than also the AWS EventiBridge envelope itself.

I suppose you could always pull a schema json (open api etc) and convert it to a pydantic schema so it could be used with powertools.

Keep in mind that the powertools parser supports many other services, rather than just evenbridge.

And one last thing, I always saw the EventBridge schema registry as a nice way to trade schemas between different services that belong to different companies. I mean, if it's all within the same organisation, why not just share the pydantic schemas via shared python repositories with utilities such artifactory etc?