Part 0: On a new kind of search engine
There is nothing special about use text to get back more text.
Sometime, you want to trade your text for a list of numbers. Maybe you want a CSV file, a map to plan your trip, or something higher dimensional. You don't want more text. You have nothing against text, but you want numbers you can run your number cruncher on to tell you something more immutable about the truth o' world.
Words really are just numbers too. So why do we keep thinking search engine ought to return text?