I mean, that is exactly what dims is doing.
If you have your traces in arviz’s InferenceData format (which I strongly recommend) and poke around with it, you’ll find that the data are stored in xarray under the hood. This allows dimensions to be accessed in much the same way as columns or rows in a pandas DataFrame, or in place of axes in numpy arrays.
Really, dims a quite an interoperable approach. You can do a lot with it once you start digging.
EDIT: Just saw this!