import { Client } from '@hashgraph/sdk';
import { HCS10Message } from '../hcs10/types';
/**
 * Creates and returns a Hedera Client based on environment variables.
 */
export declare function createHederaClient(): Client;
/**
 * HederaClient class for handling HCS-10 operations
 */
export declare class HederaClient {
    private client;
    constructor(client: Client);
    /**
     * Subscribe to messages from a topic
     * TODO: Update to use a mirror node
     */
    subscribeToTopic(topicId: string, onMessage: (message: HCS10Message) => void, onError: (error: Error) => void): Promise<void>;
}