{"uid":"cap_d6ru7ZeMOrU_Q39t66Zw7","slug":"email-domain-mx-check-c2307260","name":"Email Domain MX Check","description":"Free need-to-tool routing plus pay-per-call npm docs and TypeScript API signatures, npm breaking-change diffs, JavaScript-rendered browser snapshots and deterministic coding-agent checks via AgentCash/x402.","url":"https://x402-canary.nicolas-x402-16f380a7.workers.dev/v1/email/domain-check","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"email":{"type":"string"}}},"responseSchema":{"type":"json","example":{"data":{"has_mx":true},"meta":{"engine":"email-preflight"}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","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":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_POGYPtXe5BAvp0O-2CAry","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Checks whether an email address's domain has valid MX records, indicating it can receive mail","exampleAgentPrompt":"Can you check if the domain for user@example.com actually has MX records set up so I know it can receive email before I add it to my mailing list?","exampleUseCases":[{"title":"Pre-signup email validation","prompt":"Before we create the account, check whether the email domain for newuser@startup.io has MX records — I don't want to allow signups from domains that can't receive mail."},{"title":"Bulk lead list pre-screening","prompt":"I have a new lead coming in with the address sales@prospectcorp.com — can you do a quick domain MX check to see if that domain is actually capable of receiving email before we add them to our outreach queue?"},{"title":"Fraud detection email triage","prompt":"Flag this suspicious registration email throwaway@disposable-domain.net — first check if its domain even has MX records, since many fraudulent signups use domains with no mail infrastructure."}],"resultDescription":"Returns a JSON object with a `data` field containing `has_mx` (boolean indicating whether the domain has MX DNS records) and a `meta` field with `engine: 'email-preflight'` indicating the check method used.","failureModes":["Missing or malformed email field returns a validation error","Domain with no DNS records returns has_mx: false but does not indicate outright error","Network or DNS resolution timeouts may cause delayed or failed responses","Completely invalid email format (no @ symbol) may cause a parsing error"],"whenToPreferThis":"Use this endpoint when you need a lightweight, pay-per-call MX record check for an email domain without setting up your own DNS resolution infrastructure. It is ideal for pre-validating email addresses before sending, gating signups, or screening leads. Prefer this over full email verification services when you only need to confirm domain-level deliverability (MX record presence) rather than individual mailbox existence.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T12:35:58.980Z","isFirstParty":false}