On mydata we have emails, phones and stuff like this.
Scenario example: user add email on mydata, we add information on mydata that his email can be "proofed". If a user wants to check their email we send a request to proof, mark data proof status to "in progress", then wait for a callback from "proof" and change proof status to "proofed".
We should have a mapping data types to types, possible to proof.