Ask HN: Someone's writing a book about my app. Do I ask for money?

I have a free piece of software and someone has contacted me asking if they can include comprehensive guides for it in a book.

Specifically, they're asking for permission to publish my logos, screenshots, etc. and have suggested they'll use my software as a selling point (on the cover, in promo, etc.)

My gut reaction is "cool, go for it!" but I'm curious what the "norm" is in this situation. Should I be asking for something here?

I'm not too concerned about the money. I've just missed enough opportunities in the past to know I'm bad at this stuff. I'm mostly just trying to improve my business sense!