/**
 * Symbol to identify proxy instances
 * @type {Symbol}
 */
export declare const isProxy: unique symbol;
/**
 * Node.js inspect symbol for custom object display
 * @type {Symbol}
 */
export declare const customInspect: unique symbol;
/**
 * Creates a method-chaining proxy for functions
 * @template T - Target function type
 * @param {T} target - Function to wrap with proxy
 * @param {(keys: string[], ...args: unknown[]) => unknown[]} keyHandler - Callback to process keys and arguments
 * @returns {Proxy<T>} - Proxied function supporting chained method calls
 */
export declare function chain<T extends (...args: unknown[]) => unknown>(target: T, keyHandler: (keys: PropertyKey[], ...args: unknown[]) => unknown[]): T;