/**
 * @license
 * Copyright 2025 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */
import type { Config, MCPServerConfig } from '../config/config.js';
import type { ToolRegistry } from './tool-registry.js';
import { MCPDiscoveryState } from './mcp-client.js';
import type { EventEmitter } from 'node:events';
/**
 * Manages the lifecycle of multiple MCP clients, including local child processes.
 * This class is responsible for starting, stopping, and discovering tools from
 * a collection of MCP servers defined in the configuration.
 */
export declare class McpClientManager {
    private clients;
    private readonly toolRegistry;
    private readonly cliConfig;
    private discoveryPromise;
    private discoveryState;
    private readonly eventEmitter?;
    constructor(toolRegistry: ToolRegistry, cliConfig: Config, eventEmitter?: EventEmitter);
    /**
     * For all the MCP servers associated with this extension:
     *
     *    - Removes all its MCP servers from the global configuration object.
     *    - Disconnects all MCP clients from their servers.
     *    - Updates the Gemini chat configuration to load the new tools.
     */
    private unloadExtension;
    /**
     * For all the MCP servers associated with this extension:
     *
     *    - Adds all its MCP servers to the global configuration object.
     *    - Connects MCP clients to each server and discovers their tools.
     *    - Updates the Gemini chat configuration to load the new tools.
     */
    private loadExtension;
    private disconnectClient;
    discoverMcpTools(name: string, config: MCPServerConfig): Promise<void> | void;
    /**
     * Initiates the tool discovery process for all configured MCP servers.
     * It connects to each server, discovers its available tools, and registers
     * them with the `ToolRegistry`.
     */
    discoverAllMcpTools(): Promise<void>;
    /**
     * Stops all running local MCP servers and closes all client connections.
     * This is the cleanup method to be called on application exit.
     */
    stop(): Promise<void>;
    getDiscoveryState(): MCPDiscoveryState;
}