Extension properties in the AS2 namespace

[evanp]

Section 2.1 says:

Implementations MAY also use additional properties and values not defined in the JSON-LD @context with the understanding that any such properties will likely be unsupported and ignored by consuming implementations that use the standard JSON-LD algorithms.

I think the best practice as of this date is to use an extension context. Adding ad-hoc properties can cause conflicts if they are used with different semantics by different implementations.

[evanp]

It's not clear whether additional properties are namespaced, or should be. Does this whole sentence belong in extensions?

[evanp]

I think this sentence and the previous one could be removed, and we just say, "For properties and types not defined in the Activity Vocabulary, see Extensions".

[trwnh]

We could move the requirements regarding "augmenting the context" and "using additional properties" to Section 5 "Extensibility", and then refocus Section 2.1 "JSON-LD" into explaining the media type considerations that people publishing AS2 documents should be aware of. A subsection on "context injection" and another subsection on "media type equivalence" could fit well here.