+Summary:        Supports using pandoc with citeproc

The summary should say what it is (is-a). "ghc-pandoc-siteproc is a supports using pandoc with citeproc" makes no sense.

Here's the first line summary on the GH repo: The pandoc-citeproc executable can be used as a filter with pandoc to resolve and format citations using a bibliography file and a CSL stylesheet.

That could be shortened to: A pandoc filter to resolve and format citations using a bibliography and a CSL stylesheet