Are you sure you're not thinking of billing alerts? AFAIK there is still no way to set spending limits at GCP.
replyI'll admit it's a bit obscure But there is info here.
replyhttps://docs.cloud.google.com/apis/docs/capping-api-usage
Or you can do it programmatically.
https://docs.cloud.google.com/billing/docs/how-to/disable-bi...