{"uid":"cap_fJXwb1_TR0xGDVI_Yb43L","slug":"sitecheck-web-intel-mta-sts-validator-2cd22fd3","name":"SiteCheck Web Intel MTA-STS Validator","description":"Checks MTA-STS for a mail domain: the _mta-sts TXT record (v=STSv1 and id) and the HTTPS policy file (mode enforce, testing or none, the MX patterns and max_age). Reports whether the record and the policy are both present and whether the policy's version is valid. Does not test the mail servers themselves.","url":"https://api.webintel-api.workers.dev/api/security/mta-sts-validator?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["domain"],"properties":{"domain":{"type":"string","description":"Mail domain such as gmail.com (required)"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_-E1eUU0TtSoUBGXt_9RML","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Validates a mail domain's MTA-STS configuration by checking the _mta-sts TXT DNS record and the HTTPS policy file, reporting their presence, mode, MX patterns, and max_age.","exampleAgentPrompt":"Can you check the MTA-STS configuration for example.com — I want to know if the _mta-sts TXT record is present, what policy mode is set (enforce, testing, or none), and whether the HTTPS policy file is valid?","exampleUseCases":[{"title":"Email security audit for new domain","prompt":"We just set up MTA-STS for our company domain acme.com — can you verify the _mta-sts TXT record is in place, confirm the policy file is reachable over HTTPS, and tell me if the mode is set to enforce?"},{"title":"Diagnose MTA-STS misconfiguration","prompt":"Emails to our domain techstartup.io are bouncing from strict senders — can you check our MTA-STS setup and tell me if the DNS record and policy file are both valid and what mode they're showing?"},{"title":"Monitor third-party mail domain posture","prompt":"I need to verify whether our vendor's mail domain supplierco.net has MTA-STS properly configured before we start exchanging sensitive emails — check the policy mode, MX patterns, and max_age for me."}],"resultDescription":"Returns whether the _mta-sts TXT DNS record exists with v=STSv1 and an id, whether the HTTPS policy file at /.well-known/mta-sts.txt is reachable and syntactically valid, the policy mode (enforce, testing, or none), the list of MX host patterns allowed, the max_age value, and an overall summary of whether both the record and policy are present and valid.","failureModes":["Domain does not exist or has no DNS records — returns absence flags","_mta-sts TXT record missing — returns record not found","HTTPS policy file unreachable or returns non-200 — reports policy fetch failure","Policy file present but malformed or missing required fields — reports invalid policy","Network timeout fetching the policy file — may return error or partial result","Domain parameter missing from query — likely returns 400 or validation error"],"whenToPreferThis":"Use this endpoint when you need a quick, automated check of a mail domain's MTA-STS posture without standing up your own DNS resolver or HTTP client logic. It is ideal for email security audits, onboarding checks, compliance monitoring, and troubleshooting MTA-STS deployment issues. It does not test the actual mail servers, so pair it with SMTP-level checks if full delivery path validation is needed.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-24T12:38:36.866Z","isFirstParty":false,"canonicalSlug":"sitecheck-web-intel-mta-sts-validator-2cd22fd3"}