Hi all, Not sure where to ask this, but does anyone know if this is a valid encounter participant type: const PARTICIPANT_TYPE_CALLBACK = { coding: [ { system: 'http://terminology.hl7.org/CodeSystem/participant-type', code: 'CALLBCK', display: 'Callback contact', }, { system: 'http://terminology.hl7.org/CodeSystem/participant-type', code: 'AUTOAGENT', display: 'Automated AI Agent', }, ], text: 'Automated AI Agent', }; Am I using the right system url, and can I "extend" a default/existing participant type this way? When I create an Encounter with this participant type array, Medplum only displays the "Automated AI Agent" in the Participant's Type field when viewing the Encounter details. But in the JSON view, it seems like both participant types are retained.

A couple things to take into account [Here](https://build.fhir.org/valueset-encounter-participant-type.html) is the ValueSet that

Encounter.participant.type

has an "extensible" binding to. That binding strength suggests that you should use codes from the ValueSet if one fits, BUT you can use other codes if nothing in the ValueSet adequately represents your concept. The system URL for the CALLBCK code is actually

http://terminology.hl7.org/CodeSystem/v3-ParticipationType

, so I would change that. I am not sure what exactly what AUTOAGENT means as a code, but you should make up your own system url for it that references your organization to differentiate it from the standard system namespace urls. Including multiple codings in a CodeableConcept is valid but typically used to map the same concept across different systems, not to combine different semantic meanings. > When I create an Encounter with this participant type array, Medplum only displays the "Automated AI Agent" in the Participant's Type field when viewing the Encounter details. But in the JSON view, it seems like both participant types are retained. The Medplum react component UI showing only "Automated AI Agent" is correct. That's what the text field is, so our react components show that as display. You can always choose to display specific codings as well in your own UI.

Thank you for your response!