HL7 FHIR R4

Build FHIR API endpoints

This skill is a reference for building healthcare REST endpoints on FHIR R4, such as Patient, Observation, Encounter, and MedicationRequest. It covers mandatory fields, allowed enum values, HTTP responses and errors, and coding systems like LOINC, SNOMED, RxNorm, and ICD-10. SMART on FHIR authorization, Bundles, transactions, and paged search are included.