Errors

The Gateway uses HTTP status codes and a JSON error response to distinguish request failures. Check both the HTTP status and the machine-readable error code; do not make application decisions from the human-readable message alone.

Status	Meaning	What to check
`400`	Request shape or values are invalid	Required fields, formats, claim filters, and policy constraints
`401`	API key is missing or invalid	Authorization header, key status, and environment
`403`	The key or request is not permitted	Key scope, tenant membership, or relying-party policy
`404`	The resource does not exist or is no longer available	Resource ID, tenant, and session retention window
`409`	The request conflicts with current tenant configuration	Select the required active relying-party instance
`413`	Request body exceeds the endpoint limit	Reduce the request payload
`429`	Rate limit reached	Back off and retry with jitter; avoid tight polling loops
`5xx`	Gateway or dependency failure	Retry safe operations with bounded backoff and report the request ID if supplied

The exact error schema and statuses vary by operation. Use the API Reference for the response contract of the endpoint you call.