XML format: Relevance of ID and Stamp?

I'm doing some work on generating an XML import file, but am curious about the ID fields. I want to periodically regenerate the XML file (just overwrite -- without importing the potential changes a user has done).

Each connection has an ID (GUID), and this is used for links between entries (eg: an SSHShell entry referring to a Credential entry for the private key).

When I regenerate the file, should I try to keep the same ID for each entry, or is it fine to just make a new random one each time? (Basically, is referenced anywhere else besides just the file?)

Each connection also have a stamp GUID but I'm not really sure what it's for. From experimentation, I noticed that if I leave it off, after import RDM modifies the file and adds a Stamp value to every entry. I also noticed if I modify the entry in the RDM interface, a new stamp value is generated.

What is 'stamp' used for? Am I safe to just assign a random GUID, or should I leave it off, or something else?

Aside, is there any documentation on the XML format itself available somewhere?