diff --git a/chain/route.go b/chain/route.go
index c42f516..cf86bfd 100644
--- a/chain/route.go
+++ b/chain/route.go
@@ -86,18 +86,18 @@ func (r *Route) connect(ctx context.Context) (conn net.Conn, err error) {
 		return nil, ErrEmptyRoute
 	}
 
+	network := "ip"
+	node := r.nodes[0]
+
 	defer func() {
 		if err != nil && r.chain != nil {
 			if v := metrics.GetCounter(metrics.MetricChainErrorsCounter,
-				metrics.Labels{"chain": r.chain.name}); v != nil {
+				metrics.Labels{"chain": r.chain.name, "node": node.Name}); v != nil {
 				v.Inc()
 			}
 		}
 	}()
 
-	network := "ip"
-	node := r.nodes[0]
-
 	addr, err := resolve(ctx, network, node.Addr, node.Resolver, node.Hosts, r.logger)
 	if err != nil {
 		node.Marker.Mark()
diff --git a/metrics/metrics.go b/metrics/metrics.go
index 79277e5..ca6b3d9 100644
--- a/metrics/metrics.go
+++ b/metrics/metrics.go
@@ -3,15 +3,24 @@ package metrics
 type MetricName string
 
 const (
-	MetricServicesGauge                     MetricName = "gost_services"
-	MetricServiceRequestsCounter            MetricName = "gost_service_requests_total"
-	MetricServiceRequestsInFlightGauge      MetricName = "gost_service_requests_in_flight"
-	MetricServiceRequestsDurationObserver   MetricName = "gost_service_request_duration_seconds"
-	MetricServiceTransferInputBytesCounter  MetricName = "gost_service_transfer_input_bytes_total"
+	// Number of services. Labels: host.
+	MetricServicesGauge MetricName = "gost_services"
+	// Total service requests. Labels: host, service.
+	MetricServiceRequestsCounter MetricName = "gost_service_requests_total"
+	// Number of in-flight requests. Labels: host, service.
+	MetricServiceRequestsInFlightGauge MetricName = "gost_service_requests_in_flight"
+	// Request duration historgram. Labels: host, service.
+	MetricServiceRequestsDurationObserver MetricName = "gost_service_request_duration_seconds"
+	// Total service input data transfer size in bytes. Labels: host, service.
+	MetricServiceTransferInputBytesCounter MetricName = "gost_service_transfer_input_bytes_total"
+	// Total service output data transfer size in bytes. Labels: host, service.
 	MetricServiceTransferOutputBytesCounter MetricName = "gost_service_transfer_output_bytes_total"
-	MetricNodeConnectDurationObserver       MetricName = "gost_chain_node_connect_duration_seconds"
-	MetricServiceHandlerErrorsCounter       MetricName = "gost_service_handler_errors_total"
-	MetricChainErrorsCounter                MetricName = "gost_chain_errors_total"
+	// Chain node connect duration histogram. Labels: host, chain, node.
+	MetricNodeConnectDurationObserver MetricName = "gost_chain_node_connect_duration_seconds"
+	// Total service handler errors. Labels: host, service.
+	MetricServiceHandlerErrorsCounter MetricName = "gost_service_handler_errors_total"
+	// Total chain connect errors. Labels: host, chain, node.
+	MetricChainErrorsCounter MetricName = "gost_chain_errors_total"
 )
 
 type Labels map[string]string