diff --git a/Descriptors/GPXDescriptor.h b/Descriptors/GPXDescriptor.h
index bc6a91280..ef86a517a 100644
--- a/Descriptors/GPXDescriptor.h
+++ b/Descriptors/GPXDescriptor.h
@@ -57,7 +57,7 @@ template <class DataFacadeT> class GPXDescriptor : public BaseDescriptor<DataFac
     }
 
   public:
-    GPXDescriptor(DataFacadeT *facade) : facade(facade) {}
+    explicit GPXDescriptor(DataFacadeT *facade) : facade(facade) {}
 
     void SetConfig(const DescriptorConfig &c) final { config = c; }
 
diff --git a/Descriptors/JSONDescriptor.h b/Descriptors/JSONDescriptor.h
index fecbea51f..e7e5e9c70 100644
--- a/Descriptors/JSONDescriptor.h
+++ b/Descriptors/JSONDescriptor.h
@@ -70,7 +70,7 @@ template <class DataFacadeT> class JSONDescriptor : public BaseDescriptor<DataFa
     ExtractRouteNames<DataFacadeT, Segment> GenerateRouteNames;
 
   public:
-    JSONDescriptor(DataFacadeT *facade) : facade(facade), entered_restricted_area_count(0) {}
+    explicit JSONDescriptor(DataFacadeT *facade) : facade(facade), entered_restricted_area_count(0) {}
 
     void SetConfig(const DescriptorConfig &c) final { config = c; }