I'm not sure I understand the question correctly.
Yes, it is possible to
carry information in the url. Try for example to click the upload image on
the right side of
http://en.wikipedia.org/wiki/Wikipedia:WikiProject_India/Wiki_Loves_Monumen…
. That could give for example:
http://commons.wikimedia.org/w/index.php?title=Special:UploadWizard&cam…
which carries the identifier, the description, latitude and longitude.
Yup. See [1] & [2] for more documentation
[1] <