API Annotations question

[Jan Stolarek]

Alan, devs,

since API annotations were added some data types in the source code have extra comments related to 
these annotations, eg.

-- | A type or class declaration.
data TyClDecl name
  = -- | @type/data family T :: *->*@
    --
    --  - 'ApiAnnotation.AnnKeywordId' : 'ApiAnnotation.AnnType',
    --             'ApiAnnotation.AnnData',
    --             'ApiAnnotation.AnnFamily','ApiAnnotation.AnnWhere',
    --             'ApiAnnotation.AnnOpen','ApiAnnotation.AnnDcolon',
    --             'ApiAnnotation.AnnClose'
    FamDecl { tcdFam :: FamilyDecl name }

I'm totally clueless about what these comments mean. Where can I find an explanation? Couldn't 
find anything on the wiki.

Janek