Making the tool easy to use and allowing it to just immediately post on Twitter is much different than simply providing a model online that people can download and run themselves.

If you are providing a tool for people, YES you are responsible to some degree.

Think of it this way. I sell racecars. I'm not responsible if someone buys my racecar and then drinks and drives and dies. Now, I run an entertainment venue where you can ride along in racecars. One of my employees is drunk, and someon dies. Now I am responsible.