An Interface is an abstract type that includes a certain set of fields that a type must include to implement the interface.
NodeInterface is the base for all types.
Guideline Id.
Guideline name.
Guideline color.
Guideline internal url.
BETA The default language of the Guideline, or null if not set.
BETA Languages in which the Guideline is available.
Paginated list of LibraryPage items for Guideline.
BETA A list of GuidelinePages that belong to this Guideline