import OpenAI from "openai";
import type { AIGateway } from "../config";
/**
 * Returns a lazy singleton OpenAI client for CUA mode.
 *
 * CUA requires direct OpenAI access (Responses API + built-in `computer` tool).
 * Throws ConfigurationError if OPENAI_API_KEY is missing, or if the resolved
 * gateway for this call is not "none" (a non-"none" gateway routes through a
 * proxy that does not expose the Responses API).
 *
 * @param gateway - The resolved gateway for this call (defaults to "none").
 *   Pass the per-step / per-call resolved gateway, not the global one — this
 *   is what enables hybrid runs where the global gateway is `openrouter` but
 *   one step opts into CUA with `gateway: "none"`.
 */
export declare function getOpenAIClient(gateway?: AIGateway): OpenAI;
/** @internal Reset client singleton. Used for testing only. */
export declare function resetOpenAIClient(): void;