I would like to add properties to an existing vocabulary with the REST API, but don’t understand how I must define the vocabulary in the payload. I tried this structure:
The API is designed to encourage treating vocabularies as somewhat fixed, rather than adding or removing properties from existing vocabularies, the API is more set up around adding a new vocabulary (you can specify properties for a new vocabulary as part of the creation of the vocabulary itself).
So, the API actually doesn’t allow you to set a vocabulary ID directly like this.
This error message could be more clear, certainly.