I think we should be allowed to use perfect here: You have drunk all my beer!
Based on what I could gather so far : 'vy-' is a prefix which means 'out' (vychod, vychazet etc.) so here combined with 'pít', it gives to the verb a perfective nuance ('drank out' -> finished drinking?). Can anyone confirm that for me?
It means to drink it all . The vy makes it perfective with the meaning of completing the drinking by drinking all the fluid in question.
Very often you will find corresponding verbs in German to use aus- where Czech has vy-. So trinken is pít and austrinken is vypít.