I most exclusively use oXygen Editor for editing JSON, YAML for many reasons. This editor can accept a JSON schema to provide context sensitive editing with a defined YAML (aka like automations) to assist in knowing what is needed where and what cannot be inserted where.
I would assume that they do exist somewhere because getting message like “extra keys not allowed” implies the YAML was parsed against a Schema to determine if it is valid.
If these do exist, where can they be found?