I wasn’t able to find anything on the API page or forums about this.
Is there a better way than raycast to check if a terrain grass cell is sloped? surely there is
What do you need it for exactly? if you need it to make the player not able to climb steep things, there is Humanoid.maxslopeangle for that, although i doubt that’s what you want. if you give more information there may be another way to get your ultimate goal if you explain more. i’m no terrain expert (never use terrain) so i cannot confirm nor deny anything specifically about your question