[Harp-L] my recording rights?

["Brian Stear" <brianstear@xxxxxxxxxxxxx>]

I recently got asked to play harmonica on a song someone is recording for a CD. He's then going to tour with the group. He's very happy the way it turned out. He paid me some gas money and plans to give me a healthy discount at his used record store. At the time I said that was fine.
  My question is this; 
 Since we verbally agreed ( no handshake ) on compensation, am I within my rights to ask to be given credit on the CD for my part on the song? Mind you, I don't want royalties or anything. I just realized after the fact that without my name on the CD, I really don't have any way to prove my work. I can say I did it, but have no way of proving it. For example, I used to play with Koko Taylor, but I don't have any pictures or something in writing to prove it.
This won't happen again. I'll ask the person this next week when I see him. Hope it works out, but.......
 Is this something in the future that should always be in writing?

Thanks,
Brian