/**
 * Unwrap a backend error body for re-emission on a translated door.
 *
 * The Anthropic/Responses adapters run over the OpenAI-chat backend; when it
 * fails, its body is already an OpenAI error envelope. Re-wrapping that JSON
 * string as the `message` of a fresh `api_error` (the old behavior) both
 * double-encodes the message and misclassifies caller errors — a 400
 * `invalid_request_error` from the backend must stay an
 * `invalid_request_error` on the door.
 */
export declare function unwrapUpstreamError(detail: string, options?: {
    readonly preserveMetadata?: boolean;
}): {
    type: string;
    message: string;
    code?: string;
    param?: string;
};