Read, add and delete attributes with the tab position in Type Definition.

I would like Read, add and delete attributes with the tab position in Type Definition.

I can write the code in VBA or C# not important for me.

I see in library the object :

TypeDefinition tdFunctions = EB.TypeDefinitions.FindItemByKind(ObjectKind.FunctionTypes);



TypeItem item = tdFunctions.TypeItems.FirstOrDefault();

int i = item.AttributeDefinitions.Count;

Tihs objects is good (TypeDefinition , TypeItem , AttributeDefinitions) but I don't see the function Add and Remove.
In the item AttributeDefinition, I d'ont have the information about the tab.