Spaced repetition systems have gotten better

I see a lot of discussion about SRS, and I think most can agree they have improved.

What I would like to see covered is a more vague area, but almost more important:

It’s the space in between reading/understanding something and the SRS. There are almost no standalone tools dedicated to creating flashcards easily from existing programs (web browser, PDF readers etc.) into popular SRS (Anki, Mochi etc.). They should work almost as OS additions to make everything feel native and frictionless; I don’t need another standalone tool that does X Y and Z, I just need some sort of pipe into an SRS that is Mac friendly and does the job whilst not being in the way.

If someone knows of such a tool, I would love to hear about it.

I've written my own flashcards app (Fresh Cards) and once in a while, users ask if there's a way to import flashcards from things like web pages and PDF files, but to be honest, I still don't know how it would work, so maybe you can help me.

From a user standpoint, would it be an interactive process where you highlight things and then click a button to say "turn this into a flashcard", or would it be an automated tool that would scan the content and come up with a list of questions and answers t hat would test the material for you? What criteria would be used to determine what's worth turning into a question and answer? And how granular should the question be? I've seen demos of things that pick out specific facts, like dates or names, from the text to turn into questions, but that might not be that useful to quiz for some material. It seems like a very open-ended process to me, so it would be hard to get right for everyone's needs.