Thanks for all the reviews and comments! I've included the big-endian requirement so the proposed language is now as below. I'll leave the vote open until after the May holiday.
Rok UUID ==== * Extension name: `arrow.uuid`. * The storage type of the extension is ``FixedSizeBinary`` with a length of 16 bytes. .. note:: A specific UUID version is not required or guaranteed. This extension represents UUIDs as FixedSizeBinary(16) *with big-endian notation* and does not interpret the bytes in any way.
