Firebase Realtime database rules "Unknown variable 'request'."

It looks like a documentation mistake because in Firestore you would write request.auth.uid while in the RTDB you just write auth.uid.

{
  "rules": {
    "some_path": {
      "$uid": {
        // Allow only authenticated content owners access to their data
        ".read": "auth != null && auth.uid == $uid",
        ".write": "auth != null && auth.uid == $uid"
      }
    }
  }
}