Which resource documents the capabilities and supported operations of an implementation?

• A. StructureDefinition
• B. CodeSystem
• C. CapabilityStatement
• D. ValueSet

Answer: (C)

This tests understanding of where an implementation’s capabilities and supported operations are described in FHIR. The CapabilityStatement resource is the authoritative description of what a server or client can do: which resources are supported, what interactions are allowed (read, vread, update, patch, delete, search, etc.), which search parameters exist, supported data formats (JSON/XML), and any other capabilities or operations the system exposes. It is typically exposed at the server’s metadata endpoint (often retrieved with a GET to /metadata) so clients can discover exactly how to interact with that implementation. Other resources serve different purposes: StructureDefinition defines the shape and constraints of resources or extensions; CodeSystem defines a set of codes; ValueSet defines a collection of codes. They do not document the overall capabilities of an implementation.