1. Introduction

This is a proposal for additional header fields to be added to email messages sent by email distribution lists. The content of each new field is typically a URL - usually mailto [RFC2368] - which locates the relevant information or performs the command directly. MTAs generating the header fields SHOULD usually include a mailto based command, in addition to any other protocols used, in order to support users who do not have access to non-mail-based protocols.

Implementing these fields will be optional. Significant functionality and convenience can be gained by including them, however. Many list managers, especially as the proposal first gains acceptance, MAY choose to implement only one or two of the fields. The List-Help field is the most useful individual field since it provides an access point to detailed user support information, and accommodates almost all existing list managers command sets. The List-Subscribe and List-Unsubscribe fields are also very useful, but cannot describe some list manager syntaxes at this time (those which require variable substitution). See appendix A.5 for an explanation.

The description of command syntax provided by the fields can be used by mail client applications to provide simplified and consistent user access to email distribution list functions. This could take the form of menu items, push buttons, or other user interface elements. The intent is to simplify the user experience, providing a common interface to the often cryptic and varied mailing list manager commands.

Consideration has been given to avoiding the creation of too many fields, while at the same time avoiding the overloading of individual fields and keeping the syntax clear and simple.

The use of these fields does not remove the requirement to support the -Request command address for mailing lists [RFC2142].