[galaxy-dev] History/Dataset UUID instead of integer ID?

Hello, I am working with blend4j and bioblend to interact with galaxy. In general, the API seems to require the UUID of a dataset/history, etc. I may be missing something obvious, but I am not finding great ways to obtain this from cheetah substitutions. For example, I can use ${history.id} or ${ output.id} to get the integer ID of that dataset/history. ${output.uuid} is not recognized. I am looking here as a reference: https://github.com/galaxyproject/galaxy/blob/e73d90c94edc63d181c30bd1942918a... https://github.com/galaxyproject/galaxy/blob/dev/lib/galaxy/model/__init__.p... and would have expected UUID to get exposed in some manner. Is there a standard way to obtain the UUID? Thanks, Ben