/**
* gtk_widget_class_query_action:
- * @widget_class: a `GtkWidget`Class
+ * @widget_class: a `GtkWidget` class
* @index_: position of the action to query
* @owner: (out): return location for the type where the action was defined
* @action_name: (out): return location for the action name
- * @parameter_type: (out): return location for the parameter type
- * @property_name: (out): return location for the property name
+ * @parameter_type: (out) (nullable): return location for the parameter type
+ * @property_name: (out) (nullable): return location for the property name
*
* Queries the actions that have been installed for
- * a widget class using gtk_widget_class_install_action()
+ * a widget class using [method@Gtk.WidgetClass.install_action]
* during class initialization.
*
* Note that this function will also return actions defined