The sane way to do this (if you wanted to) would be to give the AI a debit card with a small balance to work with. If funds get stolen, you know exactly what the maximum damage is. And if you can't afford that damage, then you wouldn't have been able to afford that card to begin with.
But since people can cancel transactions with a credit card, that's what people are going to do, and it will be a huge mess every time.
It's not like a credit card is all that different from a debit card in terms of cancellations. If this becomes a big enough problem, I would imagine that card issuers will simply stop accepting "my agent did it" as an excuse in chargeback requests.
But since people can cancel transactions with a credit card, that's what people are going to do, and it will be a huge mess every time.