Facebook's Blenderbot

 Good indication of what Facebook has been doing in this space..  From O'Reilly: 

Facebook open-sources BlenderBot
Facebook AI has open-sourced BlenderBot, an open domain chatbot. It’s said to “feel more human,” because it blends a diverse set of conversational skills—including empathy, knowledge, and personality—together in one system. The model has 9.4 billion parameters, which is 3.6 times more than the largest existing system. Here’s the complete model, code, and evaluation setup.