Tells you the records to publish, and gates a send on them — but cannot check DNS itself
Built, with limitsA sending domain is a real record carrying its own SPF, DKIM and DMARC state. The exact records to publish are generated from the domain rather than looked up, so that half is correct with no resolver at all, and the campaign send route consults an authentication gate that refuses only on positive evidence a recorded domain's SPF or DMARC is missing. 'Unknown' never blocks a send: refusing because this deployment cannot resolve DNS would be an outage wearing a safety label. Metrics report real queued and blocked counts per stream, per day, computed from the recipient rows.
Needs: Two separate things, neither of them a key you can set. A DNS resolver: there is none in this process, so every published-record status stays unknown, and TXT_RESOLVER is the seam that starts answering the moment one exists. And the transactional provider's webhook feed, which is where bounce rate, complaint rate and delivered count would come from — they are reported as null rather than zero, because zero would read as 'nothing bounced'.
Will not: Report SPF, DKIM or DMARC as passing when nothing has actually been checked — with no resolver in this process, a published-record status stays unknown rather than becoming a guess. Treat an owner's attestation as evidence. It is stored separately from the three status columns on purpose, so a later real check can contradict it.
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