When a builder or contractor wants you to provide references, what is the most common way to present them?

Do they typically just want names and numbers or do they want to see specific project information?

Opinions?
Thanks-
mike

either way, i did have a pix portfolio
at one time.....but word of mouth
( especially GC to GC) is powerful....

As Sparky said, you can't beat word of mouth. It almost guarantees you the work, usually without bidding.