The sending domains of the site, the domains its emails go out from: for each, whether it is verified, where verification stands, the exact DNS records it needs, when they were last checked and what the user does next. Call it for questions about the sender: before the first broadcast from the user's own domain, when the "from" address looks wrong, when emails land in spam, or when verification seems stuck. An empty list is itself the answer: the site has no domain of its own and emails go out from the default Getsitecontrol sender.

next_action and next_action_hint of the list say what to do for the site as a whole; each domain carries its own. Domains are added in the Getsitecontrol admin; verify_email_domain checks one now. The list describes the setup only, nothing about individual emails, bounces or statistics. Every domain comes in one response.