Extension

https://build.fhir.org/ig/HL7/fhir-shorthand/reference.html#defining-extensions

If you don’t explicitly define a context then will default to Element, which will result in the following warning in the QA report Review the extension type for assistance-needs-ext: extensions should not have a context of Element unless it's really intended that they can be used anywhere.

Extension: AssistanceNeedsExtension
Id: assistance-needs-ext
Title: "Assistance Needs"
Description: "An extension to capture a set of assistance needs."
Context: Condition
* value[x] only CodeableConcept
* valueCodeableConcept from AssistanceNeedsValueSet (required)

Extensions are not supported as stand-alone resources.