Minor nitpick but the NSA does not employ agents, but rather analysts and (sometimes) operators. "Agents" in the IC sense are people that do your bidding, i.e. recruiting someone to insert a USB drive into a target device.
Sometime in the Post-9/11 era they transitioned to 'Investigators' and the majority of them got a big stick up their rear ends and it has become a trying, adversarial relationship every time they come out.