A couple of weeks ago I essentially failed the Turing test (took to be an AI). I found it a bit annoying, so I built Possibly Made By A Human. It tracks your keyboard use (not the content, ms between keystrokes etc) and produces a signature for you. It can of course be spoofed, but that also takes some effort.
This is one of the coolest tech things I've seen in a while. Can you explain how the "Check a document" works? I'm not sure I understand how you would check if the timing aligns based only on the text content.
It's a very poorly written way of saying that instead of storing your text it uses a hash of your text to sign. When you want to check the signature you only need to hash the text to check, again without touching the server.
Actually made by a human, signature: https://possiblymadebyahuman.com/7PuEdZs1i1