import type { ReadStream } from "node:fs";
import type { H3Event } from "h3";
export declare const DEFAULT_CHAT_MAX_BODY_BYTES: number;
export declare const DEFAULT_UPLOAD_MAX_FILE_BYTES: number;
export declare const MAX_CHAT_ATTACHMENTS_PER_MESSAGE = 20;
export declare const UPLOAD_ALLOWED_MIME_PREFIXES: string[];
export declare function isAllowedUploadMimeType(mimeType: string): boolean;
export declare function readBody<T = any>(event: H3Event): Promise<T>;
export declare function readBodyWithSizeLimit<T = any>(event: H3Event, maxBytes?: number): Promise<T>;
export declare function streamFile(stream: ReadStream): ReadableStream;