As per #11058 (comment), it would be ideal to be able to augment API field documentation with things such as:

• Proxy specific implementation status (i.e. whether a feature is implemented in Envoy yet, whether it's alpha or stable)
• OOB data such as example secure configurations (which may also be proxy specific).

The solution is to have a proxy manifest file that acts as a map from API field to additional information. This will be glued by protodoc (for Envoy at least) in to the final end user docs.