Shout out to HL7 and its bastard offspring, FHIR! Here's an example of the problem: https://www.hl7.org/fhir/patient.html https://www.hl7.org/fhir/patient.html

Shout out to HL7 and its bastard offspring, FHIR! Here's an example of the problem: https://www.hl7.org/fhir/patient.html https://www.hl7.org/fhir/patient.html That's the FHIR Patient Object. Seems reasonable? Look at the cardinality. Almost everything in that object is optional. Open some of the field types, like Identifier: https://www.hl7.org/fhir/datatypes.html#Identifier https://www.hl7.org/fhir/datatypes.html#Identifier Yep that's right, everything is optional there too. {active: true} That's a valid FHIR Patient Object.