http://hl7.org/fhir/StructureDefinition/contactpoint-purpose|5.2.0

Indicates the reasons that are considered appropriate to reach out to the contactable entity via this particular mechanism.  Only for use when the ContactPoint is NOT nested inside ExtendedContactDetail.
typedestination
baseDefinitionhttp://hl7.org/fhir/StructureDefinition/Extension
typehttp://hl7.org/fhir/StructureDefinition/Extension
Extension.value[x].typehttp://hl7.org/fhir/StructureDefinition/CodeableConcept