I'm slowly adding metadata to https://github.com/ocharles/papers. For now, I'm mainly interested in setting year and author fields on files. There are a lot of files here though, so it's difficult to to work out which need metadata and which don't.

Would it be possible to have a git annex metadata -s author='*' also have all files in the top level if they don't have an author set at all, or something? Basically, I'm looking for a way to get a view where files don't have author set at all, so I can fix that.