I thought about this but it's also a liability and puts too much strain on me.

1. Whatever limit I put needs to be completely arbitrary. 5$? 10$? 2. I cannot guarantee they will use it correctly. They might use it for the challenge. They might use it to generate harmful content. 3. It requires me to manually create and revoke keys. Candidates might want more credits. They might get leaked.

There are solutions. I just can't think of good ones.