

Zero knowledge systems
I like this idea, it’s very interesting. Yet I always end up wondering how it could go sideways.
A one time token (as in per message) seems onerous. A multi use token attesting “this is a human” could be sold to a bad actor using it to allow non-humans to masquerade as humans. We already see something like that on big social media where human accounts are sold to troll farms.

I second this. Local is the way to go for medical information.
I always recommend remaining highly skeptical about apps promising to help with anything like this. There were period tracking apps sending women’s period information to data broker companies, who would then sell it onward. That’s creepy as hell! Doing everything locally avoids intrusive data collection.