I noticed that the CHIP-0007 spec document, specifies the that a Collection's ID is a string.. The JSON Schema provided, specifies this as a string with a format of UUID. There is no mention of "UUID" at all, in the specification itself.
I'm fine with (and welcome) the JSON Schema providing this additional constraint, however, I'd suggest it be added to the human readable specification as well... or be removed from from the JSON Schema version.