Token limitations per chat

I would like the ability to limit the number of tokens each chat can use. I don't want malicious actors going onto my website and using up 1k tokens and then all other customers can't use it for a month.

I could probably afford to pay for 1 or 2 packs of additional 5k tokens if needed each month, but our company doesn't really have an enterprise level budget. Certainly not for a personal project I am trying to do to shunt the occasional batch of stupid questions out of our phone queues.