For people with Linux experience, I point to sys and proc as examples of some of the best principles of "REST" in play. You can get far exploring it and if nothing else it gives you some good discoverable clues for searching what you want.

Proxmox did something similarly nice by publishing a lot of their model via a fuse filesystem.

Imitating a filesystem like interface is a useful approach, and "REST" is the closest buzzy things to get people on that page.