export declare function stringifyError(error: unknown, format?: {
    oneline: boolean;
}): string;
/**
 * Extends an error with a new message and keeps the original as the cause.
 * This helps to keep the stacktrace intact and enables better debugging.
 * @param error - The error to extend
 * @param message - The new message to add to the error
 * @param appendOriginalMessage - Whether to add the original error message after new message
 * @returns A new error with the extended message and the original as cause
 */
export declare function extendError(error: unknown, message: string, { appendOriginalMessage }?: {
    appendOriginalMessage?: boolean | undefined;
}): Error;