docs: The `id` value cannot be overridden.
It's illegal to mask the `id` with a computable.
@@ -13,7 +13,9 @@ objects and by links between objects.
Every object has a globally unique *identity* represented by a ``UUID``
value. Object's identity is assigned on object's creation and never
changes. Referring to object's ``id`` property yields its identity as a
-:eql:type:`uuid` value.
+:eql:type:`uuid` value. Once set, the value of the ``id`` property
+cannot be changed or masked with a different :ref:`computable
+<ref_datamodel_computables>` expression.
Object types can *extend* other object types, in which case the extending
type is called a *subtype* and types being extended are called *supertypes*.
