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Playground demo key · api.reefapi.com
post/email-preflight/v1/dns_auth1 credit

Sender-domain email-authentication summary (SPF/DKIM/DMARC/MX + deliverability grade) via an inner-call to the email-health engine — REUSE, not re-implemented here (email-health owns DNS auth; this is a thin preflight wrapper).

Working example
Parameters

The sending domain (the From: address domain). Its email authentication (SPF/DKIM/DMARC/MX) is summarized via email-health.

Optional DKIM selector to look up (e.g. 'google', 's1'). If omitted, email-health autoscans common selectors.

Also run the slower DNSBL reputation pass (email-health blacklist). Default false = auth-only (SPF/DKIM/DMARC/MX), the fast pre-send check.

request preview
curl -X POST https://api.reefapi.com/email-preflight/v1/dns_auth \
  -H "x-api-key: $REEF_KEY" \
  -H "content-type: application/json" \
  -d '{"domain":"github.com"}'

Hit Send to run this endpoint live.