import { grpc } from 'google-gax';
/**
 * Interceptor for recording metrics on gRPC calls.
 *
 * This interceptor records attempt metrics at the start and completion of each gRPC call,
 * and also records Google Front End (GFE), AFE metrics such as latency and connectivity errors
 * based on the presence and value of the 'server-timing' header in the response metadata.
 *
 * @param {object} options - The gRPC call options, including method definition.
 * @param {function} nextCall - The next function to call in the gRPC request chain.
 * @returns {grpc.InterceptingCall} - The intercepting call with added metrics recording.
 */
export declare const MetricInterceptor: (options: any, nextCall: any) => grpc.InterceptingCall;