In Actionstep a Contact record can be assigned one or more contact types. A contact type is simply a way to label a Contact. For example, a Contact may be designated a Client, a Defendant, a Plaintiff, a Witness, a Lawyer, etc.
You can view the contact types assigned to a Contact at the bottom of the Edit Contact page.
To retrieve the contact types assigned to a Contact you make a GET request to the participantdefaulttypes endpoint, filtering by a specific Contact (participant) Id.
NB: For historical reasons the terms contact and participant are used interchangeably in some areas of Actionstep, hence why endpoints and property names here use the term participant.
To add a contact type to a Contact you make a POST request to the participantdefaulttypes endpoint specifying a message body that includes the Contact (Participant) Id and the Contact (Participant) Type Id.
To remove a contact type from a Contact you make a DELETE request to the participantdefaulttypes endpoint. The DELETE request requires the Contact (Participant) Id and the Contact (Participant) Type Id to be specified in the URL separated by "--".