import { Message, ModelName } from '../types.js';
/**
 * Summarizes the input messages using the AI model and returns a single message object with the summary.
 * Optionally, includes the previous summary in the summarization process.
 *
 * @param {Message[]} messages - The array of messages to be summarized.
 * @param {Message} [previousSummary] - Optional. A previous summary to include in the summarization process.
 * @param {ModelName} [modelName] - Optional. The AI model to use for summarization. Default is determined by chat configuration.
 * @returns {Promise<Message>} - A Promise that resolves to the summary message.
 */
export declare function summarizeChatMessages(messages: Message[], previousSummary?: Message, modelName?: ModelName): Promise<Message>;