import type { Client } from '@modelcontextprotocol/sdk/client/index.js';
import { McpClientConfig } from '@n8n/config';
import type { McpTool } from './types';
export interface McpCacheLogger {
    warn(message: string, meta?: object): void;
    debug(message: string, meta?: object): void;
}
interface CachedClient {
    client: Client;
    mcpTools: McpTool[];
    lastUsedAt: number;
    epoch: number;
    detachLifecycle: () => void;
}
interface GetOrConnectOpts {
    logger?: McpCacheLogger;
    onExecutionCancellation?: (handler: () => void) => void;
    onExecutionFinish?: (handler: () => void) => void;
}
export declare class McpClientsManager {
    private readonly config;
    private readonly activeClients;
    private readonly pendingConnections;
    private readonly cleanupTimer;
    private connectionEpoch;
    private readonly exitHandler;
    constructor(config: McpClientConfig);
    get size(): number;
    getEntry(key: string): CachedClient | undefined;
    getOrConnect(key: string, factory: () => Promise<{
        client: Client;
        mcpTools: McpTool[];
    }>, opts?: GetOrConnectOpts): Promise<{
        client: Client;
        mcpTools: McpTool[];
    }>;
    refresh(key: string): void;
    remove(key: string, logger?: McpCacheLogger): void;
    private registerLifecycleCleanup;
    private removeIfCurrent;
    evictStale(): void;
    private enforceMaxSize;
    private attachTransportLifecycle;
    shutdown(): void;
}
export {};