Currently the GWToolset namespace just shows json (see for example http://commons.wikimedia.beta.wmflabs.org/w/index.php?title=GWToolset:Metadata_Mappings/Multichill/anefo.json&action=edit).
In the first iteration of the campaign namespace Yuvi included pretty display of the json and a nice json editor. I can't show an example of the pretty display because in the next iteration it became a gallery (for example https://commons.wikimedia.org/wiki/Campaign:wlm-nl), but I can give an example of the json edit interface: https://commons.wikimedia.org/w/index.php?title=Campaign:wlm-nl
I would like to have pretty display of json for the GWToolset namespace. It's probably just flipping a switch somewhere, but I don't have an idea yet which one.