☰ Scenario Validation of the search parameter definitions in the CapabilityStatement
And CapabilityStatement contains definition of search parameter "_count" of type "number" for resource "DocumentReference"
INFO
rest.where(mode = 'server').resource.where(type = 'DocumentReference' and searchParam.where(name = '_count' and type = 'number').exists()).exists()
["BooleanType[true]"]