(I suggest any comments to this post be discussed under this 'post' instead of the 'forum topic' I started before with the exact same title and message).
I just uploaded a document that discusses the various challenges involved in defining the scope and serialization of a type record. In that document we also proposed how to mitigate those challenges. The document also includes a few JSON examples of type records.
We encourage the group to review the document and get a discussion going on this topic. If we get reasonable agreement on the proposed items, we will release a type registry prototype shortly.
Link to the document: https://rd-alliance.org/filedepot?fid=367