As for wording used we can perhaps steal from the How do I find a community? #85, which includes community_quest:
"* An official LiveJournal community, community_quest (http://www.livejournal.com/userinfo.bml?user=community_quest), was created as a place where other LiveJournal users can help you find a community that relates to your interests." - inserting the words 'syn' and 'feed' instead of community.
N.B. The descriptions used in FAQ #85 are different to the descriptions used in #125 - the Official Journals FAQ. The wording there is:
* syn_quest: Closely related to syn_promo; used to request the names of syndicated feeds that already exist if they cannot be found in syn_promo. -- http://www.livejournal.com/userinfo.bml?user=syn_quest
* community_quest: Closely related to community_promo; used to request the names of communities that already exist if they cannot be found in community_promo. -- http://www.livejournal.com/userinfo.bml?user=community_quest