Overlays, are they allowed

Hey, I was trying to make sense of the whole user agreement etc, I was wondering are things like the Op.gg overlay allowed or are they deemed 3rd party cheating software? Obviously its nothing like scripting or anything that helps with actual game play, its just user info and I have seen some streamers using it and advertising it on twitch etc so I was just wondering if its the type of thing you can be banned for etc.
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