{ "ok": true, "domain": "zhihu.com", "generated_at": "2026-08-08T18:09:01-05:00", "cache": { "hit": true, "ttl": 0 }, "score": { "total": 69, "label": "Fair", "categories": { "dns": 70, "mail": 90, "security": 77, "network": 20, "availability": 60 }, "category_weights": { "dns": 25, "mail": 20, "security": 25, "network": 10, "availability": 20 }, "items": [ { "category": "dns", "title": "IPv4 (A)", "max_points": 30, "earned_points": 30, "lost_points": 0, "detail": "1 IPv4 address(es) detected." }, { "category": "dns", "title": "IPv6 (AAAA)", "max_points": 10, "earned_points": 0, "lost_points": 10, "detail": "0 IPv6 address(es) detected." }, { "category": "dns", "title": "Name server redundancy", "max_points": 20, "earned_points": 20, "lost_points": 0, "detail": "2 NS record(s); 2 or more required." }, { "category": "dns", "title": "SOA record", "max_points": 10, "earned_points": 10, "lost_points": 0, "detail": "Authoritative zone record." }, { "category": "dns", "title": "DNSSEC chain", "max_points": 15, "earned_points": 0, "lost_points": 15, "detail": "Both DS and DNSKEY are required." }, { "category": "dns", "title": "CAA policy", "max_points": 5, "earned_points": 0, "lost_points": 5, "detail": "Certificate authority restriction." }, { "category": "dns", "title": "DNS propagation", "max_points": 10, "earned_points": 10, "lost_points": 0, "detail": "Agreement between public resolvers." }, { "category": "mail", "title": "MX records", "max_points": 20, "earned_points": 20, "lost_points": 0, "detail": "2 MX record(s)." }, { "category": "mail", "title": "SPF", "max_points": 25, "earned_points": 25, "lost_points": 0, "detail": "SPF policy published." }, { "category": "mail", "title": "DMARC", "max_points": 25, "earned_points": 25, "lost_points": 0, "detail": "DMARC policy published." }, { "category": "mail", "title": "DKIM", "max_points": 20, "earned_points": 20, "lost_points": 0, "detail": "A DKIM selector was verified." }, { "category": "mail", "title": "MTA-STS", "max_points": 5, "earned_points": 0, "lost_points": 5, "detail": "Mail transport policy." }, { "category": "mail", "title": "TLS-RPT", "max_points": 5, "earned_points": 0, "lost_points": 5, "detail": "TLS reporting policy." }, { "category": "security", "title": "Valid TLS certificate", "max_points": 55, "earned_points": 55, "lost_points": 0, "detail": "124 day(s) remaining." }, { "category": "security", "title": "Certificate lifetime", "max_points": 10, "earned_points": 10, "lost_points": 0, "detail": "Full points require at least 30 days remaining." }, { "category": "security", "title": "HTTP security headers", "max_points": 35, "earned_points": 12, "lost_points": 23, "detail": "3 of 9 evaluated headers detected." }, { "category": "network", "title": "PTR reverse DNS", "max_points": 30, "earned_points": 0, "lost_points": 30, "detail": "PTR not detected." }, { "category": "network", "title": "IPv4 diversity", "max_points": 35, "earned_points": 20, "lost_points": 15, "detail": "Two or more IPv4 addresses receive full points." }, { "category": "network", "title": "IPv6 connectivity", "max_points": 35, "earned_points": 0, "lost_points": 35, "detail": "AAAA availability." }, { "category": "availability", "title": "DNS resolution", "max_points": 40, "earned_points": 40, "lost_points": 0, "detail": "At least one address family must resolve." }, { "category": "availability", "title": "HTTP response", "max_points": 40, "earned_points": 0, "lost_points": 40, "detail": "HTTP/2 405 " }, { "category": "availability", "title": "HTTPS final URL", "max_points": 20, "earned_points": 20, "lost_points": 0, "detail": "Final URL uses HTTPS." } ], "methodology": "Each category is normalized to 100. 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