What does 2 Samuel 3:13 mean?

David replied, 'Alright, I'll make a deal with you. But there's one thing: you can't even see me unless you bring Michal, Saul's daughter, when you come.' 2 Samuel 3:13 - Modern Text Bible

(David agrees but insists on the return of his first wife, Michal, as a condition, both for personal and political reasons.)