It is a very nice idea. Suppose at work you have a large pdf that explains some concepts you need for the sw you need to develop. Since it is a big pdf, you can't spend the time to completely read it to find the info you need. So you just ask the pdf something like - which is the formula i need to normalize my data, given inputs x and y. Then it provides an answer and you then can go into more details by asking more questions around that answer. You could also ask for pseudo code in any language.

Seems to me a much faster way of getting what you need to do the job.

The caveat is that you need to upload the document which has a big chance of containing confidential info.