Rate limit exceeded

rate_limit_exceeded HTTP 429

The per-key request budget for the current window is spent. Every response carries RateLimit-Limit, RateLimit-Remaining and RateLimit-Reset, so a client can slow down before hitting this; this response also carries Retry-After.

Budgets are per key, so splitting work across more concurrent workers on the same key does not buy throughput.

How to react to this in code

Switch on the code member — rate_limit_exceeded — which is stable. Do not parse the type URI: it points here, and where "here" is may change.