User-agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.5) Gecko/20050116
That said, this is what VisualAge (Smalltalk, Java) did (but didn't have all
the bells & whistles), and caused quite an uproar because people couldn't
"see" their files.
There could be a standard XML representation. Being eclipse-ish, the
shema, as well as tools that can handle it would be publicly available.
As far as I have heard, VA's file format was closed, and corruptions
were not that rare.