Can I purchase additional API requests on a legacy free Sanity plan?

Unfortunately, you're correct to be concerned. Based on the Sanity pricing documentation, Legacy Free plans without a credit card on file cannot purchase additional API requests or go into overage.

Here's what the documentation states:

"Any resource usage beyond the quotas will be billed at overage rates, except for Free projects (no overages allowed) or on a Legacy Free plan without a credit card, which may be temporarily deactivated instead."

So when you hit 100% of your quota, your project may be temporarily deactivated rather than allowing you to purchase additional resources.

Your options:

1. Add a credit card to your Legacy Free plan - This should allow you to go into overage and purchase additional API requests as needed. You can do this in Manage under your project settings.

2. Upgrade to a paid plan - Consider upgrading to the Growth plan, which includes more generous quotas and allows overages. New projects get a 30-day free trial of Growth (no credit card required initially).

3. Optimize your API usage - Review your request patterns to see if you can reduce unnecessary API calls, implement caching, or use the API CDN more effectively for read operations.

4. Contact support - If you're close to the limit and need immediate help, reach out to Sanity support to discuss your options. They may be able to provide guidance specific to your situation.

The key issue is that Legacy Free plans without payment information are treated similarly to the current Free plan - no overages allowed, which means the project gets paused when you hit the limit.