[traceroute66]

> Credit card numbers relayed over the phone are not deterministic...

I don't know the last time you relayed card details over the phone, but the last 100 times I did it, the agent did one of two things:

    (a) Said "Please wait while I turn off recording"; or
    (b) Transferred the call to an automated system that read the card details via the phone keypad input and then took back control of the call afterwards.

Relaying card details over the phone is a problem that has been comprehensively solved. You don't need an LLM for it !

> But finding 90% or 95% or 99% is pretty good

I would humbly suggest that you are over-estimating the capabilities of an LLM. ;)