Fully depends on the kids, type of play date, ages etc... most of my DCs friends parents aren’t precious about food so when they come to my house the snack draw is always a firm favourite. If I’m doing food it will always be something easy they will enjoy, pizza, hot dogs etc..
Don’t micromanage or have a agenda, just let the kids have fun, if they are bored then have something as a back up for them to do. You will find most kids entertain themselves.
I had a bit of a girly get together last year when restrictions where eased, 2 DDs had 2 friends each so 6 girls aged 3-6, put cupcake holder in the middle of the table with sandwiches, plain cupcakes, put some icing & sugar decorations in bowls on the table, they had a very girly princess afternoon tea and decorated their own cupcakes. No supervision, just left them to it. There were plenty of toys in the play room, there came and went in the garden. The only thing I did was grab a bunch off dress up stuff from the bedrooms and put it on a little pink rail I had in the play room so they didn’t need to go upstairs into the bedrooms.
Had a great catch up with the mums with very little distractions with the kids. There was a mess after but because it was restricted to certain parts of the house it’s far easier to clean up and I don’t have to worry about anything nice being ruined.
It also depends on what kind of house you run. Our front room is a no go area with kids on play dates but they are free to go anywhere else downstairs. Upstairs I have rules but I will vary them depending on the children. My older DCs best friends have been coming round for years, I know them, know they are well mannered and behaved kids, there parents are like me when it comes to respecting other peoples homes. So they are allowed upstairs but younger kids or ones I don’t know how they will behave it’s a no go area. Kids whose parents don’t teach them respect and discipline bad behaviour don’t get many invites back.