diff --git a/pkg/fingerprint/header_injector.go b/pkg/fingerprint/header_injector.go
index a5df455..9c71f18 100644
--- a/pkg/fingerprint/header_injector.go
+++ b/pkg/fingerprint/header_injector.go
@@ -51,6 +51,7 @@ func RegisterDurationMetric(registry *prometheus.Registry, buckets []float64, pr
 		Namespace: prefix,
 		Name:      "fingerprint_duration_seconds",
 		Buckets:   buckets,
+		Help:      "The duration of fingerprinting requests in seconds",
 	}, []string{"ok", "header_name"})
 }
 
diff --git a/pkg/proxyserver/proxyserver.go b/pkg/proxyserver/proxyserver.go
index 1580b02..3aec41d 100644
--- a/pkg/proxyserver/proxyserver.go
+++ b/pkg/proxyserver/proxyserver.go
@@ -263,6 +263,7 @@ func (server *Server) registerMetrics() {
 	server.metricRequestsTotal = pm.NewCounterVec(prometheus.CounterOpts{
 		Namespace: prefix,
 		Name:      "requests_total",
+		Help:      "The total number of requests processed by fingerproxy",
 	}, []string{"ok", "negotiated_protocol"})
 
 	// ...