shidduchim calls

Sure, why not?

Depends if you said good things or not.

If someone whom I trust to say good things about me told me they got a call about me, I’d be happy to hear about it. It’s always nice to know that people are thinking about you and trying to set you up.

there could be circumstances either way so it really depends, if we want to get super detailed though im sure you could come up with basic guidelines. i dont see any reason that you should ever have to tell (if you think it will give them a boost it might b nice) but but there might b times that it wouldnt b good to say anything

Then don’t tell him/her that you got a call about him/her. They might start asking you what you said, and it could be very awkward. Even if you think you can avoid letting on that you said something negative, there’s a very good chance that they might figure it out or at least suspect something. (have you ever read “Diamond Dust” by Reva Pomerantz?)

Or they may find out that the guy heard xyz about them and put two and two together and figure out it was you.

It actually happened to me at least once that someone told me that he told the guy negative things about me. And it wasn’t even the reference – it was the shadchan!