{"uid":"cap_5w3lHcsYSg-9pjYN3DQ5I","slug":"is-email-hosted-by-posteo-6c75de92","name":"Is Email Hosted by Posteo","description":"Is the domain's email hosted by posteo? Looks up the MX records (Cloudflare DoH) and matches them against posteo's mail-exchanger patterns, returning yes/no, the MX hosts and which matched. Provider detection for deliverability, sales and migration work. $0.01 per lookup.","url":"https://email.intel.rallylive.ca/email/hosted-by/posteo?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$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_UazHH9gBfsx45Pcva4sw0","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 given domain's email is hosted by Posteo by querying MX records via Cloudflare DoH and matching against Posteo's mail-exchanger patterns.","exampleAgentPrompt":"Can you check if the email for protonmail.com is hosted by Posteo — look up their MX records and tell me whether Posteo is their mail provider?","exampleUseCases":[{"title":"Pre-sales email provider research","prompt":"Before I reach out to leads at datenschutz-experte.de, can you check whether their email is hosted by Posteo? I want to know their mail provider before crafting my outreach."},{"title":"Email migration vendor audit","prompt":"We're auditing which of our client domains use Posteo as their email host — can you check if gruene-energie.org is currently on Posteo's mail servers?"},{"title":"Deliverability segmentation check","prompt":"I need to segment my mailing list by provider — can you tell me if the domain posteo-nutzer.de is actually hosted by Posteo, including which MX hosts matched?"}],"resultDescription":"Returns a yes/no answer indicating whether the domain's email is hosted by Posteo, the full list of MX hosts discovered via Cloudflare DoH, and which specific MX hostnames matched Posteo's known mail-exchanger patterns.","failureModes":["Domain does not exist or has no MX records — returns no match with empty MX list","Cloudflare DoH lookup failure — DNS resolution error returned","Invalid or malformed domain input — request rejected","Posteo changes MX patterns — detection may return false negatives until patterns are updated","Rate limiting or payment failure — 402 or 429 response"],"whenToPreferThis":"Choose this endpoint when you need a fast, single-call determination of whether a specific domain routes email through Posteo, particularly for sales intelligence, deliverability segmentation, or migration auditing workflows where Posteo is the target provider. It is preferable to generic MX lookup tools because it handles Posteo pattern matching automatically and returns a clean yes/no result.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-23T00:55:23.469Z","isFirstParty":false,"canonicalSlug":"is-email-hosted-by-posteo-6c75de92"}