import { AxiosError, Method } from 'axios';
/**
 * Pure token-source selection: prefer the keyring value, then the env value.
 * Throws a clear, secret-free error when neither is present. Kept pure (no IO)
 * so every branch is unit-testable; the impure keyring/env reads live in
 * resolveToken().
 */
export declare function resolveApiToken({ keyringValue, envValue, }: {
    keyringValue?: string | null;
    envValue?: string | null;
}): string;
/**
 * Parse an RFC 7231 `Retry-After` header into a non-negative millisecond delay.
 * The header is either delta-seconds (a bare integer) OR an HTTP-date — a bare
 * `parseInt` turned a date into `NaN`, so `setTimeout(NaN)` fired immediately and
 * defeated the 429 backoff. Returns null when absent or unparseable (including the
 * obsolete non-IMF-fixdate forms) so the caller falls back to exponential backoff;
 * clamps to a finite, non-negative delay.
 */
export declare function parseRetryAfterMs(retryAfter: string | undefined, now?: number): number | null;
export declare function sanitizeAxiosError(err: AxiosError): boolean;
export declare function wrapLexwareError(err: unknown): unknown;
export declare function lexwareRequest<T = unknown>(method: Method, path: string, data?: unknown, params?: Record<string, unknown>): Promise<T>;
export declare function lexwareUpload<T = unknown>(path: string, fileBuffer: Buffer, fileName: string, contentType: string, uploadType?: 'voucher'): Promise<T>;
export declare function getWebhookPublicKey(): Promise<string>;
export declare function __resetWebhookKeyCache(): void;
export declare function parseContentDispositionFileName(header: string): string | undefined;
export declare function lexwareDownload(path: string, accept?: string): Promise<{
    data: Buffer;
    contentType: string;
    fileName?: string;
}>;