Error glossary

Status	Meaning	Normal response
400	Invalid or incomplete request.	Correct the input; do not retry unchanged.
401	Authentication is missing, expired, or invalid.	Refresh the supported session or credential.
403	Authenticated but not permitted.	Check role, origin, entitlement, or policy.
404	Route or resource not found.	Verify the URL, resource identifier, and selected environment. Shopify merchants should also confirm the current Aabhas block is active.
409	Current state conflicts with the operation.	Read the domain error and resolve readiness or idempotency.
429	Rate or capacity limit.	Honor retry guidance; avoid immediate loops.
500	Unexpected server failure.	Record identifier and time; do not guess configuration changes.
503	Required service temporarily unavailable.	Retry only as directed and report persistent failures.
504	Operation exceeded a gateway or service deadline.	Check final job state before creating a duplicate run.

Validation, authentication, authorization, not-found, and conflict errors should not be retried unchanged. Transient server, capacity, or timeout errors require bounded recovery rather than infinite browser retry.