@Override
    public void check(HealthCheckService.HealthCheckRequest request,
        StreamObserver<HealthCheckService.HealthCheckResponse> responseObserver) {

        if (LOGGER.isDebugEnabled()) {
            LOGGER.debug("Received the gRPC server health check with the service name of {}", request.getService());
        }

        HealthCheckService.HealthCheckResponse.Builder response = HealthCheckService.HealthCheckResponse.newBuilder();
        response.setStatus(HealthCheckService.HealthCheckResponse.ServingStatus.SERVING);

        responseObserver.onNext(response.build());
        responseObserver.onCompleted();
    }
By my test, consul didn't send the service.

@param request          service
@param responseObserver status
oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/remote/health/HealthCheckServiceHandler.java