I was clicking on the gRPC Specification link in the laucher repo https://github.com/kolide/launcher/blob/master/docs/launcher.md which points to https://github.com/kolide/agent-api/blob/master/agent_api.proto but github's Jedi gatekeeper tells me I should believe it does not exist

That’s a private/archived repo. I don’t know what this is supposed to be

Looks like that landed here: https://github.com/kolide/launcher/blob/master/pkg/pb/launcher/launcher.proto

That;s a easy PR if sopmeone wants their name in the commit list 😉