The classes.json endpoint is used to retrieve information about all the Feature Classes you have access to with your AI Packs. All the features (polygons) returned by the features.json endpoint have both an individual uuid for unique identification, and a feature class, which also has a uuid. The feature class (such as "Building") allows you to code specific patterns of behavior in your application when features of that specific type are returned – whether to control z order and styling for visualization purposes, or to inspect and use the metadata as part of your workflow.
https://api.nearmap.com/ai/features/v4/classes.json?apikey={your_nearmap_api_key}
NOTE: Human-readable descriptions of Feature Classes should NOT be used in application code, as we reserve the right to adjusts them. The uuid of each feature class is immutable and will always be associated with that semantic definition. It can therefore be mapped to your preferred description for exposure in your application or used internally for mapping the right application behavior.