Foursquare has already done the hard work of finding matching restaurants, so the trickiest part of building this MVP is finding a way to generate structured data from natural language. The great thing about tools like wit, Luis, and api.ai is that they make this part so easy that you can build an MVP like the above in an afternoon. In our experience, 3rd party tools are an excellent way to build quick prototypes. You could just as quickly build a bot to find videos with the YouTube API, or products from Product Hunt.