agent

1. id - A unique identifier assigned by the annotator to the first meaningful and descriptive reference to an agent. This id is case sensitive. When annotating a later
   mention of the same referent as an agent, there is no need to re-specify the id.
2. nested-source - Added to an agent annotation when the agent reference is the source of a private state/speech event. It is a list of agent ids beginning with the writer and ending with the id for the immediate agent being referenced. For instance, w,smith,miller would capture the idea that the writer quotes somebody called Smith who in turn quotes somebody called Miller.
3. nested-target - In the present version of the scheme, this field is not used. Targets are specified in attitude annotation frames.
4. agent-uncertain - Use when you are uncertain as to whether or not the agent is the correct source of a private state/speech event.
   
   Possible values: somewhat-uncertain, very-uncertain

NOTE: Please see Annotating Agents for more detailed instructions and examples.