Would you tell your SO that one of your close friends used to be your friend with benefits?

I had a FWB and we got close during that time. Not like lovers, but we became better friends. I still go out with him sometimes to play badminton. We haven't seen each other for half a year, because we were both on exchange studies somewhere else. I'm staying for the whole year, while he's done with his exchange program.

He will visit me this weekend and will sleep on my floor for two nights. There will be one other friend with us as well.

There's nothing more than friendship between us, but we have a deal that if neither of us has someone and we're both willing, we hook up (hasn't been tested yet, he got himself a girlfriend and before they broke up I got my boyfriend).

Is that something my boyfriend should know? (We're together 2 or 3 months)