Comment by thaumasiotes

> In a data language there's no comment erasure happening between the producer and the consumer, so comments are just dangerous as they would without doubt evolve into a system of annotations -- an additional layer of communication which would then not be standardized at all and which then would grow into a wild west of nonstandard features and compatibility workarounds.

But there's nothing stopping you from commenting your JSON now. There's no obligation to use every field. There can't be, because the transfer format is independent of the use to which the transferred data is put after transfer.

And an unused field is a comment.

    {
      "customerUUID": "3"
      "comment": "it has to be called a 'UUID' for historical reasons"
    }

If this would 'without doubt' evolve into a system of annotations, JSON would already have a system of annotations.