I think that's typically how it goes. Save someone's life and they thank you. Usually I'm-

[He was going to say better than this. But maybe not lately. Has he been keeping up on his thank yous lately? Tony's eyes drift away as he seriously considers that. Then he looks back, smiling again.]

Well. Thank you. For saving my life.

[Of course as he looks back to say that he registers what he's looking at, and it happens to be a familiar arm. The hoodie ends up thrust into him because he's too startled to accept it in time.]

Oh. You- [Suddenly he's got a million things he wants to say. Very first on the list is bringing attention to that arm. But if Bucky still looks like that, he doesn't know what their relationship is like. Or if he recognizes Tony at this point. He saved him, so he probably doesn't want to kill him at least, but that leaves a wide range of possibilities. His mouth works silently, starting and aborting thoughts as he holds the rumpled hoodie in front of him.]

Damn. [And he sounds both impressed and shaky, although that could just be the cold.] I guess I shouldn't be surprised.