Designing chat bots may be hard. I remember the first time I was working on chat bots, it was very hard to sketch out the flow of how the bot would work. I just made scripts up in my mind as I was coding, and sometimes you just get lost in your thoughts.
Twine https://twinery.org/ is an open source tool to help one in designing chat bots experiences. An example of a chat bot I designed with twine https://github.com/peterokwara/PeteBakery
You can also play through your own story to simulate how it would play out in real life
Check it out and feel free to leave any comments and your own views about it!