import { CoreMessage, LanguageModel, ToolCall, ToolInvocation, ToolSet } from 'ai';
import { Message } from '@ai-sdk/ui-utils';
/**
 * Chat handler class to manage chat requests and responses
 */
export declare class ChatHandler {
    private model;
    private tools?;
    private localTools?;
    private instructions?;
    private messageHistory;
    private maxTokens;
    private messageTokenCount;
    /**
     * @param {Object} config - Configuration object
     * @param {LanguageModel} config.model - Language model instance to use for chat
     * @param {ToolSet} [config.tools] - Optional tools configuration
     * @param {string} [config.instructions] - Optional system instructions
     * @param {string} [config.modelId] - Optional model identifier to determine context window automatically
     * @param {number} [config.maxTokens] - Optional maximum tokens (overrides automatic detection)
     */
    constructor({ model, tools, instructions, modelId, maxTokens, }: {
        model: LanguageModel;
        tools?: ToolSet;
        instructions?: string;
        modelId?: string;
        maxTokens?: number;
    });
    /**
     * Processes chat requests, managing message history and token limits
     * @param {Request} req - Incoming request object
     * @returns {Promise<Response>} Streaming response
     */
    processRequest(req: Request): Promise<Response>;
    addMessageToHistory(message: Message | CoreMessage): Promise<void>;
    handleToolCall(toolCall: ToolCall<string, unknown>): Promise<ToolInvocation | null>;
    trimHistoryByTokenLimit(): Promise<void>;
    clearHistory(): void;
}