Building a bot is not overly complicated but building a bot is a little underwhelming if that's all you do with it. Integrating artificial intelligence, to me, feels like a must because it provides that next level of interaction that makes it worth while. AI is what will make your bot feel like you're not interacting with a bot... at least until it tells you that it doesn't understand what you're asking when you say "hello", but we just need to account for those things.