There is no one right answer to this question, as the best solution will depend upon the specifics of your scenario and how the user would reasonably expect the bot to respond. However, as your conversation complexity increases dialogs become harder to manage. For complex branchings situations, it may be easier to create your own flow of control logic to keep track of your user's conversation.
To inspire the next generation of explorers, NASA reaches out to students in schools, community organizations, and public events. A star robotic ambassador is “Rov-E,” a close replica of real NASA Mars rovers. Through Amazon Lex, NASA staff can now easily navigate Rov-E via voice commands -- an effective conversational interface when speaking with large crowds. Multi-turn dialog management capability enables Rov-E "to talk,” answering students’ questions about Mars in an engaging way. Integration with AWS services allows Rov-E to connect and scale with various data sources to retrieve NASA’s Mars exploration information.
Operator calls itself a “request network” aiming to “unlock the 90% of commerce that’s not on the internet.” The Operator app, developed by Uber co-founder Garrett Camp, connects you with a network of “operators” who act like concierges who can execute any shopping-related request. You can order concert tickets, get gift ideas, or even get interior design recommendations for new furniture. Operator seems to be positioning itself towards “high consideration” purchases, bigger ticket purchases requiring more research and expertise, where its operators can add significant value to a transaction.