Queries are the backbone of any literary agent’s business. As long as they are accepting queries, they are open for business, thereby there is even the slightest possibility that an author can get their book represented and subsequently published. As a result of that there are plenty of articles written on how to write they ever important query for an author. On the opposite hand, aspiring agents (like me) aren’t so lucky. How are we supposed to know if we should request pages? I think it’s a matter of personal taste, but it’s not just about what you prefer. If you’re working for an agent, and they have specific guidelines (ie: romantic fiction, or science fiction) you have to accept or reject queries based on their tastes as well.
Long story short, keep that in mind if you’re trying to get an internship with an Agent, they way you answer the queries they send you is important
If you don’t know what a literary agent is/does Nathan Bransford gives a pretty good general overview on his blog!