diff --git a/force_bdss/kpi/base_kpi_calculator_model.py b/force_bdss/kpi/base_kpi_calculator_model.py
index 77e2991c4f3f36754baa13940dbfac41a8b36a6e..bebf5899ed618f43b3d8821dadfe7adc7622e447 100644
--- a/force_bdss/kpi/base_kpi_calculator_model.py
+++ b/force_bdss/kpi/base_kpi_calculator_model.py
@@ -19,11 +19,11 @@ class BaseKPICalculatorModel(ABCHasStrictTraits):
     #: Specifies binding between input slots and source for that value.
     #: Each InputSlotMap instance specifies this information for each of the
     #: slots.
-    input_slot_maps = List(Instance(InputSlotMap))
+    input_slot_maps = List(Instance(InputSlotMap), visible=False)
 
     #: Allows to assign names to the output slots, so that they can be
     #: referenced somewhere else (e.g. the KPICalculators).
-    output_slot_names = List(String())
+    output_slot_names = List(String(), visible=False)
 
     def __init__(self, factory, *args, **kwargs):
         self.factory = factory
diff --git a/force_bdss/mco/base_mco_model.py b/force_bdss/mco/base_mco_model.py
index d9969a8b4c796d474b263048405cb67f0c7513c3..f1e545a579e9a986bb2a57147b7f0ec30f79d7bc 100644
--- a/force_bdss/mco/base_mco_model.py
+++ b/force_bdss/mco/base_mco_model.py
@@ -18,7 +18,7 @@ class BaseMCOModel(ABCHasStrictTraits):
                        transient=True)
 
     # A list of the parameters for the MCO
-    parameters = List(BaseMCOParameter)
+    parameters = List(BaseMCOParameter, visible=False)
 
     def __init__(self, factory, *args, **kwargs):
         self.factory = factory
diff --git a/force_bdss/mco/parameters/base_mco_parameter.py b/force_bdss/mco/parameters/base_mco_parameter.py
index 5e09fcd7ce669f0fbd3dcd972c4ae6912ac5c617..e075750af36d8430b5feb9a823d4fcf9fc7368c1 100644
--- a/force_bdss/mco/parameters/base_mco_parameter.py
+++ b/force_bdss/mco/parameters/base_mco_parameter.py
@@ -14,10 +14,10 @@ class BaseMCOParameter(HasStrictTraits):
     factory = Instance(BaseMCOParameterFactory, visible=False, transient=True)
 
     #: A user defined name for the parameter
-    name = String()
+    name = String(visible=False)
 
     #: A CUBA key describing the type of the parameter
-    type = String()
+    type = String(visible=False)
 
     def __init__(self, factory, *args, **kwargs):
         self.factory = factory