diff --git a/libguh/plugin/deviceplugin.cpp b/libguh/plugin/deviceplugin.cpp
index 1dded900..7bf10680 100644
--- a/libguh/plugin/deviceplugin.cpp
+++ b/libguh/plugin/deviceplugin.cpp
@@ -165,6 +165,7 @@ QList<DeviceClass> DevicePlugin::supportedDevices() const
 {
     QList<DeviceClass> deviceClasses;
     foreach (const QJsonValue &vendorJson, m_metaData.value("vendors").toArray()) {
+        bool broken = false;
         VendorId vendorId = vendorJson.toObject().value("id").toString();
         foreach (const QJsonValue &deviceClassJson, vendorJson.toObject().value("deviceClasses").toArray()) {
             QJsonObject jo = deviceClassJson.toObject();
@@ -200,6 +201,13 @@ QList<DeviceClass> DevicePlugin::supportedDevices() const
             QList<StateType> stateTypes;
             foreach (const QJsonValue &stateTypesJson, jo.value("stateTypes").toArray()) {
                 QJsonObject st = stateTypesJson.toObject();
+                QStringList missingFields = verifyFields(QStringList() << "type" << "id" << "name", st);
+                if (!missingFields.isEmpty()) {
+                    qWarning() << "Skipping device class" << deviceClass.name() << "because of missing" << missingFields.join(", ") << "in stateTypes" << stateTypesJson.toVariant();
+                    broken = true;
+                    break;
+                }
+
                 QVariant::Type t = QVariant::nameToType(st.value("type").toString().toLatin1().data());
                 StateType stateType(st.value("id").toString());
                 stateType.setName(st.value("name").toString());
@@ -212,6 +220,13 @@ QList<DeviceClass> DevicePlugin::supportedDevices() const
             QList<ActionType> actionTypes;
             foreach (const QJsonValue &actionTypesJson, jo.value("actionTypes").toArray()) {
                 QJsonObject at = actionTypesJson.toObject();
+                QStringList missingFields = verifyFields(QStringList() << "id" << "name", at);
+                if (!missingFields.isEmpty()) {
+                    qWarning() << "Skipping device class" << deviceClass.name() << "because of missing" << missingFields.join(", ") << "in actionTypes";
+                    broken = true;
+                    break;
+                }
+
                 ActionType actionType(at.value("id").toString());
                 actionType.setName(at.value("name").toString());
                 actionType.setParamTypes(parseParamTypes(at.value("paramTypes").toArray()));
@@ -222,6 +237,13 @@ QList<DeviceClass> DevicePlugin::supportedDevices() const
             QList<EventType> eventTypes;
             foreach (const QJsonValue &eventTypesJson, jo.value("eventTypes").toArray()) {
                 QJsonObject et = eventTypesJson.toObject();
+                QStringList missingFields = verifyFields(QStringList() << "id" << "name", et);
+                if (!missingFields.isEmpty()) {
+                    qWarning() << "Skipping device class" << deviceClass.name() << "because of missing" << missingFields.join(", ") << "in eventTypes";
+                    broken = true;
+                    break;
+                }
+
                 EventType eventType(et.value("id").toString());
                 eventType.setName(et.value("name").toString());
                 eventType.setParamTypes(parseParamTypes(et.value("paramTypes").toArray()));
@@ -229,7 +251,9 @@ QList<DeviceClass> DevicePlugin::supportedDevices() const
             }
             deviceClass.setEventTypes(eventTypes);
 
-            deviceClasses.append(deviceClass);
+            if (!broken) {
+                deviceClasses.append(deviceClass);
+            }
         }
     }
     return deviceClasses;
@@ -482,3 +506,14 @@ bool DevicePlugin::transmitData(int delay, QList<int> rawData)
     }
     return false;
 }
+
+QStringList DevicePlugin::verifyFields(const QStringList &fields, const QJsonObject &value) const
+{
+    QStringList ret;
+    foreach (const QString &field, fields) {
+        if (!value.contains(field)) {
+            ret << field;
+        }
+    }
+    return ret;
+}
diff --git a/libguh/plugin/deviceplugin.h b/libguh/plugin/deviceplugin.h
index a50a168a..86495033 100644
--- a/libguh/plugin/deviceplugin.h
+++ b/libguh/plugin/deviceplugin.h
@@ -96,6 +96,8 @@ private:
 
     QList<ParamType> parseParamTypes(const QJsonArray &array) const;
 
+    QStringList verifyFields(const QStringList &fields, const QJsonObject &value) const;
+
     DeviceManager *m_deviceManager;
 
     ParamList m_config;
diff --git a/plugins/deviceplugins/mock/devicepluginmock.json b/plugins/deviceplugins/mock/devicepluginmock.json
index b5180b0e..2495256c 100644
--- a/plugins/deviceplugins/mock/devicepluginmock.json
+++ b/plugins/deviceplugins/mock/devicepluginmock.json
@@ -39,12 +39,14 @@
                         {
                             "id": "80baec19-54de-4948-ac46-31eabfaceb83",
                             "name": "Dummy int state",
-                            "defaultValue": 10
+                            "defaultValue": 10,
+                            "type": "int"
                         },
                         {
                             "id": "9dd6a97c-dfd1-43dc-acbd-367932742310",
-                            "name:": "Dummy boo state",
-                            "defaultValue": "false"
+                            "name": "Dummy bool state",
+                            "defaultValue": false,
+                            "type": "bool"
                         }
                     ],
                     "eventTypes": [
@@ -125,12 +127,14 @@
                         {
                             "id": "80baec19-54de-4948-ac46-31eabfaceb83",
                             "name": "Dummy int state",
-                            "defaultValue": 10
+                            "defaultValue": 10,
+                            "type": "int"
                         },
                         {
                             "id": "9dd6a97c-dfd1-43dc-acbd-367932742310",
-                            "name:": "Dummy bool state",
-                            "defaultValue": "false"
+                            "name": "Dummy bool state",
+                            "defaultValue": false,
+                            "type": "bool"
                         }
                     ],
                     "eventTypes": [