This page is part of the web mail archives of SRFI 83 from before July 7th, 2015. The new archives for SRFI 83 contain all messages, not just those from before July 7th, 2015.
For what it's worth, I think that the primary information we need (and the "key" to sort libraries by) is compatibility. I would really like to be able to browse scheme libraries/URI's where every level in the hierarchy was an implementation choice mutually exclusive from all others at that level, so we wouldn't get, eg, TinyCLOS objects mixed up with Meroon objects and wouldn't find code that requires exact rationals in the directory path below an indication that signifies code which does not require them. That way if you have an application that doesn't provide exact rationals (or has a different object system) you don't wind up wasting time. So to me a scheme URI would be something like "scheme://R5RS/TinyCLOS/rationals/foo.scm" and this woud be a key into a small database that mapped it to a URL giving a web address where it could be downloaded. Bear