import { RequestOptions } from '../types/web-push';
export declare function validateEndpoint(endpoint: string): void;
export declare function validateKeys(keys: Record<string, string | Buffer>): void;
export declare function validateOptions(options: RequestOptions): void;
export declare function validateHeaders(headers: Record<string, string | string[] | number | undefined>, options: RequestOptions): void;
export declare function validateTTL(ttl: number): void;
export declare function validateContentEncoding(contentEncoding: 'aesgcm' | 'aes128gcm'): void;
export declare function validateUrgency(urgency: 'very-low' | 'low' | 'normal' | 'high'): void;
export declare function validateTopic(topic: string): void;
export declare function validateProxy(proxy: any): void;
export declare function validateAgent(agent: any, proxy: any): void;