export declare const REQUEST_ID_HEADER = "x-request-id";
export declare const RETRY_AFTER_HEADER = "retry-after";
export declare const RETRY_AFTER_MS_HEADER = "retry-after-ms";
export declare const X_SHOULD_RETRY_HEADER = "x-should-retry";
export declare const RESPONSE_HEADER_ALLOWLIST: readonly ["retry-after", "retry-after-ms", "x-should-retry"];
type HeaderSource = Request | ResponseInit | undefined;
export declare const resolveRequestId: (source: HeaderSource) => string | undefined;
export declare const filterResponseHeaders: (upstream?: HeadersInit) => Record<string, string>;
export declare const buildRetryHeaders: (status: number, upstream?: Record<string, string>) => Record<string, string>;
export {};