I've received a few questions about agents and thought I'd answer them in the next few posts, starting with, "What are agents looking for, other than a good script or manuscript?"
If you are a new writer, the agent will spend a disproportionate amount of time getting you your first contract or assignment, so what he or she is looking for is someone who will be bringing in money for some time to come. In other words, they want to be sure that you're not going to be a one-hit wonder. That's one reason why they will ask you what else you're working on or have available.
That's not your cue to bring out every old project that you've submitted but have never been able to sell. What the agent wants is fresh material, not something that's already made the rounds (how you can refresh a rejected project is another topic, and I'll try to get to that one before too long).
They're also looking for someone who will be pleasant, or at least reasonable, to work with. If they sense that you're going to be phoning them every day or exposing them to all your personal problems, they will not be keen to sign you.
Finally, they want a writer who is responsive to good feedback but also has integrity (the latter may be optional if you're an aspiring screenwriter :-)) They will be gauging how you are likely to behave when interacting with producers or editors. If you're a genius, you're allowed to be annoying, otherwise it can be a deal-breaker for an agent.