It's easy to buy one plane ticket when a person has a specific plan -- to attend a meeting or a conference, or to match up with an airbnb timeslot or something.

It's harder to buy one plane ticket for the lowest cost amongst all the different ways that plane tickets can be bought, and harder yet to do so with a lack of specificity.

So, for instance: Maybe I don't have a firm plan. Maybe I'm very flexible.

Maybe all I want to do is say "Hey, bot. I want to go visit my friend in Florida sometime in the next couple of weeks and spend a few days there as inexpensively as I can. He's in Orlando. I can fly out of Detroit or Cleveland; all the same to me. If I drive to the airport myself, I'll need a place to keep my car at or near the airport. I also want to explore renting a car in Orlando. I pack light; personal bag only. Cattle class is OK, but I prefer a window seat. Present to me a list of the cheapest options, with itinerary."

That's all stuff that a human can sort out, but it takes time to manually fudge around dates and locations and deal with different systems and tabulate the results. And there's nuances that need covered, like parking at DTW is weird: It's all off-site, and it can be cheaper and better to rent a room for one night in a nearby hotel that includes long-term parking than to pay for parking by itself.

So the hypothetical bot does a bunch of API hits, applies its general knowledge of how things flow, and comes back with a list of verified-good options for me to review. And then I get to pick around that list, and ask questions, and mold it to best fit my ideal vision of an inexpensive trip to go spend time with a friend.

In English, and without ever dealing with any travel websites myself.

"Right. So I go to Detroit on Tuesday and check in at the hotel any time after noon, and take the free shuttle to the airport the next morning at around 0400 to the Evans terminal. Also, thanks for pointing out that this airport is like a ghost town until 0600 and I might want to bring a snack. Anyway, I get on the flight, land at Orlando, and they'll have a cheap car waiting for me at Avis. This will all cost me a total of $343, which sounds great. If that's all I need to know right now, then make it so. Pay for it and put it on my calendar."

(And yeah, this is a problem that I actually have from time to time. I'd love to have a bot that could just sort this stuff out with a few paragraphs.)