I don't know how it happened, though I'd found this when I opened the box to bring out my then-new Playstation2 (One of the bigger models). As a Bond fan with a freebie in his Playstation2 box, I put it in pretty promptly and started playing.
At first, I figured that this would be almost like Metal Gear Solid (Great game series; check out MGS3) in first-person, with the shooting, the stealth, all of it. Actually, Agent Under Fire is not that. I look at it as more of a run-n-gun kind of game, and I really didn't feel like much of a spy.
Graphically, it was nothing special when it released, though it wasn't poor. The animation is done pretty well, a small bit choppy at times. AI could've been a little bit better, and this may be the cause of the animation's slight choppiness.
Gunfire is well done, not Rainbow Six 3-caliber, though nice and close. Music keeps the 007-style and is nice to hear during your play.
Lastly, the gameplay is, once more, what would be a first-person run-n-gun. This is a rather short, 12 mission game, though it was fun enough to have me return to it every once in a while. Do note that the game is not that challenging. Gameplay is not mixed up a whole lot, though there are changes to the casual-ol' gameplay, like you'll be using guided missiles in the last part of one of the missions, as well as a few missions in Bond's BMW.
If you wish for something challenging and more spy-like, go for Nightfire. However, if you were actually looking for something like this and thought you just happened to stumble upon a game based on an agent, sure, go ahead. It might be easy, though it's still enjoyable.