/**
 * envelope — MCP 响应标准化包装
 * 所有 MCP 工具返回的 content 均使用此格式
 */
/**
 * @param [opts.meta] { tool, version, responseTimeMs, source }
 * @returns 标准化响应对象
 */
export interface EnvelopeMeta {
    responseTimeMs?: number;
    tool?: string;
    source?: string;
    version?: string;
    [key: string]: unknown;
}
export interface EnvelopeOptions<T = unknown> {
    success: boolean;
    data?: T | null;
    message?: string;
    meta?: EnvelopeMeta;
    errorCode?: string | null;
}
export declare function envelope<T = unknown>({ success, data, message, meta, errorCode, }: EnvelopeOptions<T>): {
    success: boolean;
    errorCode: string | null;
    message: string;
    data: T | null;
    meta: {
        source?: string | undefined;
        responseTimeMs?: number | undefined;
        version: string;
        tool?: string | undefined;
    };
};
export default envelope;