pkg-message must contain only information that is vital to setup and operation, and that is unique to the port in question.

Setup information should only be shown on initial install, and upgrade instructions should be shown only when upgrading to the relevant version.

All committers have blanket approval to constrain existing messages to install/upgrade ranges using the UCL format specifications.

Message pruning falls under the blanket approval as well, but committers are encouraged to get maintainer input beforehand.