Errors and entitlement statuses

Entitlement responses use a machine-readable status value.

Status	Action
access_granted	Continue and, for a check call, track successful work afterward
limit_exceeded	Block or present an upgrade path
account_limit_exceeded	The Usagey operator account is out of monthly allowance; request additional volume or upgrade
insufficient_credits	Ask the customer to buy a credit pack
feature_not_in_plan	Upgrade the plan or correct its entitlement assignment
no_active_subscription	Subscribe the customer to a plan
customer_not_found	Verify the customer selector and environment
feature_not_found	Verify the feature key and environment

Do not treat every non-200 response as retryable. Retry transport failures and server errors with backoff; resolve authentication, configuration, quota, and idempotency conflicts before retrying.