I've started working on game tips. A while back we talked about what we needed to do to leave early access, and one of the things on the list was to make the game more accessible.
The example that always comes up is letting people know how to open the inventory menu. It can be painful watching people play and not knowing how to do something so simple.
I'm hoping that the game tips will be kind of intelligent. When I made a similar system for Garry's Mod, it had a tooltip explaining how to open the spawn menu. I saw that tip pop up about 200 times a day for 5 years, so I'm trying to make the system try to work out what information you could do with, based on your previous behaviours.
If you've opened the inventory menu 31 times, it probably doesn't need to show you a tip describing how to open the inventory menu.
This is still totally a work in progress, and only has 2 tips right now. We want to expand it to be more aware and use it for other things (like "this door is locked" notifications, etc.).