Error Codes

Errors render in the caller’s dialect envelope — OpenAI {"error":{message,type,code}} or Anthropic {"type":"error","error":{type,message}}. The type values are dialect-neutral:

Error type	HTTP	Meaning
invalid_request_error	400	Malformed request, a missing mandatory header, or context length exceeded
content_filter_error	400	The content was rejected by a safety filter
authentication_error	401	Missing or invalid token
permission_error	403	Not permitted — includes a token tenant that doesn’t match X-Kis-Tenant when enforcement is on
not_found_error	404	Unknown model alias
rate_limit_error	429	A rate or cost budget was exceeded (Retry-After set)
api_error	502	An upstream provider returned an error
overloaded_error	503	Every upstream failed, or the gateway is not yet ready
timeout_error	504	Upstream timed out (a canceled request is 408)

Response headers: X-Kis-Request-ID is echoed, X-Kis-Idempotent-Replay: true on an idempotent replay, and Retry-After accompanies a 429.