I don't completely understand the context of the conversation, but typically, when you say someone is "very sharp", it's a friendly way of saying the person is very smart/intelligent. That is a great compliment to have someone say that you are "very sharp" when they are referring to your abilities! You are very sharp = Estás muy lista!! "Very sharp" could also refer to something that you did that was well executed. An example might be the best way to illustrate this. "Berenice, the way you solved that problem was very sharp!" which is the same as- "Berenice, the way you solved that problem was smart and well done!" Either way, a big compliment! :) There are other ways to use the word sharp that are more colloquial and/or sarcastic, but I have to guess that was probably not the situation here! See ya! :)