/** Returns the first value of an object, or undefined if the object is empty or not provided */
export declare const firstValueOf: <T extends Record<string, unknown>>(obj?: string | T) => string | T[keyof T] | undefined;
export declare const sortObjectKeysDeep: any;
export declare const sortObjectKeys: (obj: any) => {
    [k: string]: unknown;
};
/**
 * Recursively removes empty values from an object or array.
 *
 * Empty values include:
 * - `null`
 * - `undefined`
 * - empty strings (`''`)
 * - empty arrays (`[]`)
 * - empty objects (`{}`)
 *
 * You can also optionally skip specific keys from cleaning (e.g., metadata fields).
 *
 * @param input - The input object or array to clean.
 * @param skipKeys - Optional array of keys to ignore during cleaning.
 * @returns A cleaned version of the input with all empty values removed, or `undefined` if fully empty.
 */
export declare const deepClean: (input: unknown, skipKeys?: string[]) => unknown;