{"uid":"cap_1OJi19IQ7pVAwTacWsgcD","slug":"is-email-hosted-by-postmark-99b6f78f","name":"is-email-hosted-by-postmark","description":"Is the domain's email hosted by postmark? Looks up the MX records (Cloudflare DoH) and matches them against postmark's mail-exchanger patterns, returning yes/no, the MX hosts and which matched. Provider detection for deliverability, sales and migration work. $0.01 per lookup.","url":"https://email.intel.rallylive.ca/email/hosted-by/postmark?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$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","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_JfzkLxjDMQCnUIdMgbV8k","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Checks whether a domain's email is hosted by Postmark by resolving its MX records via Cloudflare DoH and matching them against known Postmark mail-exchanger patterns.","exampleAgentPrompt":"Can you check if acmecorp.com has its email hosted by Postmark? I want to know if they're using it as their email provider.","exampleUseCases":[{"title":"Pre-sales email stack detection","prompt":"I'm about to reach out to stripe.com — can you check if they use Postmark for their email hosting? I want to know before I pitch them on a migration."},{"title":"Deliverability audit for a domain","prompt":"I need to audit sendgrid.com's email setup — can you tell me if their MX records point to Postmark and show me which hosts matched?"},{"title":"Competitor email infrastructure research","prompt":"Can you check whether mailchimp.com is using Postmark as their email provider by looking up their MX records?"}],"resultDescription":"Returns a yes/no answer indicating whether the domain's email is hosted by Postmark, along with the full list of resolved MX hosts and which specific hosts matched Postmark's known mail-exchanger patterns.","failureModes":["Domain does not exist or has no MX records — returns no match with empty host list","Cloudflare DoH lookup fails due to network timeout — request error returned","Domain provided is malformed or missing — validation error","MX records exist but do not match any Postmark pattern — returns 'no' with MX hosts listed"],"whenToPreferThis":"Use this endpoint when you need to programmatically determine if a specific domain routes its email through Postmark, particularly for sales prospecting, deliverability audits, or pre-migration analysis. Prefer this over generic MX lookup tools when you specifically need Postmark provider detection with pattern matching built in. Use the bulk sibling endpoint if checking more than one domain at a time.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-12T06:50:33.133Z","isFirstParty":false,"canonicalSlug":"is-email-hosted-by-postmark-99b6f78f"}