Packet Cover Page Extension

Canonical	../StructureDefinition/nexus-packet-cover-page
Status	draft · 1.26.0
Base	Extension (constraint)
Context	List (element)
Source	FSH · JSON

Whether this attachment packet leads with a generated cover page in the outbound render.

Overview

Absent does not mean false. The value a packet starts with is decided per send channel, so an absent extension records no choice at all -- neither that a cover page was wanted nor that it was declined. Writers SHOULD state it explicitly in both directions; readers SHOULD treat absence as "not stated" and fall back to their own channel default rather than to false.

The cover page is not a packet member. It is generated at render time from what the packet already carries and never appears in List.entry, so a consumer counting members counts chart items only.

Meaningful on an attachment packet (nexus-attachment-packet), and constrained to one: the extension's contextInvariant requires the List it rides to carry an identifier under the attachment-packet naming system, so it cannot legally be stamped on a template List or on any other kind. It asserts nothing about any other kind of List because it cannot appear on one.