import { HttpService } from '@nestjs/axios';
import { EngineExtension } from './engine.abstract';
import stream from 'stream';
export declare abstract class OAIEngineExtension extends EngineExtension {
    protected readonly httpService: HttpService;
    abstract apiUrl: string;
    abstract apiKey?: string;
    constructor(httpService: HttpService);
    onLoad(): void;
    inference(createChatDto: any, headers: Record<string, string>): Promise<stream.Readable | any>;
}