Updated all code comments, should be ok now.

Source/MQTTnet/Server/MqttServerClientConnectedEventArgs.cs

@@ -9,6 +9,10 @@ namespace MQTTnet.Server
             ClientId = clientId ?? throw new ArgumentNullException(nameof(clientId));
         }
 
+        /// <summary>
+        /// Gets the client identifier.
+        /// Hint: This identifier needs to be unique over all used clients / devices on the broker to avoid connection issues.
+        /// </summary>
         public string ClientId { get; }
     }
 }