I have 5 cats and a brand new snake so I'll admit I understand cats far better than snakes currently. In my opinion, it's a good idea to let your cat investigate in a safe way. The first day I had my setup, I let my cats investigate as long as they weren't pawing at or stressing my king out. The lid was safely on it at all times and I don't plan on them ever interacting outside of the tank. I encourage my cats to smell things when I take them out by offering them to smell and allowing them to smell the soiled substrate this way they learn what that thing over there is. After the initial curiosity, it's all about teaching them to respect her space [which for me means the whole desk she's currently on]. They aren't allowed up by the tank at all unless I invite them on to my lap while I sit there watching her where they're allowed to stay calm on my lap or forced on to the floor. It seems to me that when dealing with cats, you have to get as much of their curiosity out of their system before you can start teaching them rules about that thing. It's worse with the younger cats and if you have a cat who is really attached to you [my biggest problem is my baby's jealousy.. He keeps sitting and glaring at the tank because I've been spending a lot of time near it]. My three oldest cats haven't even noticed my snake one bit, they don't care at all.

I might be new to snakes but I've had cats half my life. I also own birds and fish so dealing with potentially harmful cats is a must.