diff --git a/lib/base/type.hpp b/lib/base/type.hpp
index fdd76d593..d1b2adb27 100644
--- a/lib/base/type.hpp
+++ b/lib/base/type.hpp
@@ -30,11 +30,13 @@
 namespace icinga
 {
 
+/* keep this in sync with tools/mkclass/classcompiler.hpp */
 enum FieldAttribute
 {
-	FAConfig = 1,
-	FAState = 2,
-	FAInternal = 32
+	FAEphemeral = 1,
+	FAConfig = 2,
+	FAState = 4,
+	FAInternal = 64,
 }; 
 
 class Type;
diff --git a/lib/livestatus/livestatusquery.cpp b/lib/livestatus/livestatusquery.cpp
index 9d904805e..053610bdc 100644
--- a/lib/livestatus/livestatusquery.cpp
+++ b/lib/livestatus/livestatusquery.cpp
@@ -655,7 +655,7 @@ void LivestatusQuery::ExecuteScriptHelper(const Stream::Ptr& stream)
 		throw;
 	}
 	delete expr;
-	SendResponse(stream, LivestatusErrorOK, JsonEncode(Serialize(result, FAState | FAConfig), true));
+	SendResponse(stream, LivestatusErrorOK, JsonEncode(Serialize(result, FAEphemeral | FAState | FAConfig), true));
 }
 
 void LivestatusQuery::ExecuteErrorHelper(const Stream::Ptr& stream)
diff --git a/tools/mkclass/class_parser.yy b/tools/mkclass/class_parser.yy
index 59e9147d3..559a9b2c5 100644
--- a/tools/mkclass/class_parser.yy
+++ b/tools/mkclass/class_parser.yy
@@ -256,6 +256,9 @@ class_field: field_attribute_list identifier identifier alternative_name_specifi
 
 		field->Attributes = $1;
 
+		if ((field->Attributes & (FAConfig | FAState)) == 0)
+			field->Attributes |= FAEphemeral;
+
 		field->Type = $2;
 		std::free($2);
 
diff --git a/tools/mkclass/classcompiler.hpp b/tools/mkclass/classcompiler.hpp
index 28df74c00..bb53c745a 100644
--- a/tools/mkclass/classcompiler.hpp
+++ b/tools/mkclass/classcompiler.hpp
@@ -55,16 +55,18 @@ struct FieldAccessor
 	{ }
 };
 
+/* keep this in sync with lib/base/type.hpp */
 enum FieldAttribute
 {
-	FAConfig = 1,
-	FAState = 2,
-	FAEnum = 4,
-	FAGetProtected = 8,
-	FASetProtected = 16,
-	FAInternal = 32,
-	FANoStorage = 64,
-	FALoadDependency = 128
+	FAEphemeral = 1,
+	FAConfig = 2,
+	FAState = 4,
+	FAEnum = 8,
+	FAGetProtected = 16,
+	FASetProtected = 32,
+	FAInternal = 64,
+	FANoStorage = 128,
+	FALoadDependency = 256
 };
 
 struct Field