DMARC + SPF + DKIM email-authentication checker / mail-auth posture audit / spoofing-resistance grader / phishing-readiness scanner / domain email security score / dmarcian-style report / pre-send deliverability check. Reads the domain's DNS TXT records, parses each protocol's record (SPF mechanisms + qualifiers, DMARC tags p/sp/rua/ruf/pct/aspf/adkim, DKIM selectors with key bits and algorithm), and returns a 0-100 score, A-F grade, and per-finding human-readable reasons explaining the score.