{"uid":"cap_GvSSqjR7Wc5RZ0NiKrp8a","slug":"dns-a-smtp-subdomain-12217362","name":"dns-a-smtp-subdomain","description":"A record of smtp.<domain>: looks up the smtp host under the domain you give (A via Cloudflare DoH) and reports whether it exists, its records and TTL. Quick existence check for common hosts like smtp without enumerating subdomains. $0.01 per lookup.","url":"https://dns.intel.rallylive.ca/dns/host/smtp/a?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$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_996dI2pxjCwfuN5b0fSmW","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":"Looks up the A record for smtp.<domain> via Cloudflare DNS-over-HTTPS and reports whether the SMTP host exists, its IP records, and TTL.","exampleAgentPrompt":"Can you check whether smtp.acmecorp.com exists as a DNS host — I need to know if there's an A record for it and what IP it resolves to?","exampleUseCases":[{"title":"Verify SMTP host before sending email","prompt":"Before I configure my mail client, can you check if smtp.fastmail.com has a valid A record in DNS and what IP it resolves to?"},{"title":"Pre-flight check for new domain setup","prompt":"I just registered newstartup.io — can you check whether smtp.newstartup.io exists in DNS yet, so I know if my email server records have propagated?"},{"title":"Audit third-party domain email infrastructure","prompt":"I need to vet a supplier before onboarding them — can you look up whether smtp.supplierdomain.com has an A record configured, and if so what the TTL is?"}],"resultDescription":"Returns whether the A record for smtp.<domain> exists, along with the resolved IP address(es), the TTL value, and the DNS response code — giving a quick picture of whether the SMTP subdomain is live and reachable.","failureModes":["Domain does not exist — NXDOMAIN response with no records","smtp subdomain not configured — NOERROR but empty answer section","Invalid or malformed domain input — API may return error or unexpected result","Cloudflare DoH upstream timeout or outage — service may return error","Network latency spike causing slow response"],"whenToPreferThis":"Choose this endpoint when you need a fast, cheap ($0.01) existence check specifically for the smtp.<domain> subdomain via Cloudflare's reliable DoH resolver, without needing to enumerate or scan subdomains broadly. Ideal for email infrastructure validation, onboarding checks, or pre-flight configuration verification where only the A record of the smtp host matters.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-21T18:56:01.449Z","isFirstParty":false,"canonicalSlug":"dns-a-smtp-subdomain-12217362"}