— Yes!

VSRE: very short reply expected (netiquette)

It is the one of the ideas, wich many have on the tip of their tongue, until some clever guy express it in a proper way.
Thank you, Panayotis Vryonis for this.

The idea is in adding VSRE to the subject of the email, so the person who you want to reply in one to five words knows that the polite formula can be skipped and reply directly with “Yes” or “Agreed” or “No”.