MediaWiki:Apihelp-query+lists-paramvalue-prop-public/en

Several visibility-related properties:
 * perm: public or private (set by owner), private is only visible to owner.
 * perm_override: hidden or approved (or not present), can be set by a moderator.
 * flagged:The list got enough flags to qualify for moderator attention.
 * hidden:The list is hidden and only visible to the owner and moderators (due to flags or explicit moderator choice).