import type { SocketIOAuthenticator } from '../lib/events/socketio';
import type { LTStartConfig } from '../types/startup';
/**
 * Build a Socket.IO handshake authenticator from the startup config.
 *
 * Uses the same JWT secret as `requireAuth` — either the explicit
 * secret from startConfig.auth.secret or the JWT_SECRET env var.
 *
 * Returns `undefined` when no secret is configured (e.g. tests or
 * deployments that intentionally skip auth), which leaves Socket.IO
 * open as before.
 */
export declare function createSocketIOAuthenticator(startConfig: LTStartConfig): SocketIOAuthenticator | undefined;