EOL:Website-api docs collections description/en

Given the identifier for a collection this API will return all metadata about the collection and the items it contains. The item list can be filtered by item type, and sorted on the listed attributes. Some items will contain an optional 'sort_field' attribute. The sort field is a user-supplied string that is a special annotation on a collection item. It may be any character string, but if it is a date, it should conform to the format YYYY-MM-DD. Taxon items will contain a 'richness_score'. Richness is a metric represented as an integer between 0 and 100, with a higher number denoting a page with rich content from a wide variety of sources. Read more about taxon richness on the updates tab of a taxon page, e.g. %{richness_url}.