Along with a corresponding field in language config in site config.
It’s consistent with pages having a description. It would be useful to a lot of sites, e.g. https://www.nytimes.com: “Breaking News, US News, World News and Videos”. Atom feeds have a feed “subtitle” element, and RSS feeds have a feed “description” element.
In terms of consistency, @will has a point here. It’s unclear from the documentation why .Site.Copyright is a “root” method, while description is a params method. Both could be argued that require translation in a multiple language setup, and both would make sense to be overriden on a page level.
That “inconsistency” occurs in the default templates, for example there’s mention of site.Params.description in opengraph.html. In contrast, within rss.xml only the page title is used where the description would be expected, where as copyright is used.
Would be glad to provide a PR for the latter if that’s welcome from @bep and mantainers, but overall it seems there’s some legacy reasoning that we’re missing here.
Yes, exactly. The presence of a site variable means that themes can be designed with site descriptions in mind, not just HTML, but other formats and data like RSS, Atom, JSON-LD, and HTML microdata.