Locator types: specification in data for entry

In biblatex it is possible to specify (via the pagination field) a “default” locator label for a given entry. So, for instance, you can in the database entry specify "pagination = {paragraph} or pagination = {page} and whenever the user specifies a locator without any specific label, the processor will automatically add an appropriate label:

\cite[11]{book} -> Book, p. 11
\cite[11]{parabook} -> Book with Paragraphs, para 11

Am I right in thinking that CSL does not provide any similar facility, but assumes that a give cite will derive the label type for any locator field expressly from the citation data, and not from any entry in the bibliographical database?

Yes, that’s the way it’s set up, with a hard-coded default label type of “page”. (While it is not part of the CSL Specification, one processor [citeproc-js] recognizes an extended set of label nicknames set within the locator string itself.)

It lists locator in the variable list too, but that doesn’t necessarily mean it’s in “CSL-JSON” then?