import type { QualitySummary } from './types';
import { type LangfuseConfig } from './langfuse';
/** Typed error for failed Langfuse Metrics API responses. */
export declare class LangfuseUpstreamError extends Error {
    status: number;
    constructor(status: number, statusText: string);
}
/**
 * Runs one Langfuse Metrics API v2 query:
 * GET {baseUrl}/api/public/v2/metrics with Basic auth (publicKey:secretKey)
 * and `query` = the JSON query object.
 */
export declare function queryMetrics(baseUrl: string, publicKey: string, secretKey: string, queryObj: unknown, timeout?: number): Promise<any>;
/**
 * Returns the caller's quality summary, or null when Langfuse is disabled,
 * unconfigured, unreachable, or a v3 server without the v2 metrics endpoint
 * (non-2xx degrades to null — never throws).
 */
export declare function getQualitySummary(cfg: LangfuseConfig, opts: {
    from: string;
    to: string;
    userId: string;
}): Promise<QualitySummary | null>;