NONE

Never include class discriminator in the output.

This mode is generally intended to produce JSON for consumption by third-party libraries. kotlinx.serialization is unable to deserialize polymorphic classes without class discriminators, so it is impossible to deserialize JSON produced in this mode if a data model has polymorphic classes.

Using this mode relaxes several configuration checks in Json. In particular, it is possible to serialize enums and primitives as polymorphic subclasses in this mode, since it is no longer required for them to have outer {} object to include class discriminator.