To add to that: The Agent Types are user defined, but there is a property there called party_type that will definitively tell you if the agent is a person or an organization or a network. There used to be a property there called is_context so that all agents of a type were considered context agents or not. We recently moved that to EconomicAgent so that it can be defined at the agent level.
One thing about that document is that it is pruned to the data that seemed useful to inter-network operations. So for example, it doesn't have the reference to is_context there at all. (I looked for that because it is one change I remember.)
(It was done as initial input to the vocabulary project.)