{"uid":"cap_uxCm_Dtl0RK44OSYj6Lo_","slug":"dkim-postmark-selector-lookup-45ffe821","name":"DKIM Postmark Selector Lookup","description":"DKIM public key for selector \"postmark\" of a domain: looks up postmark._domainkey.<domain> (TXT, Cloudflare DoH) and parses v=, k=, key type, public-key length, testing flag and whether the key is revoked (empty p=). Confirms that mail signed with the postmark selector will verify. $0.01 per lookup.","url":"https://dns.intel.rallylive.ca/dns/dkim/postmark?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$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_8DcskD8BvVxk-uTcY39CU","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 and parses the DKIM public key for the 'postmark' selector (postmark._domainkey.<domain>) of a given domain via Cloudflare DoH, returning key metadata including type, length, testing flag, and revocation status.","exampleAgentPrompt":"Can you check whether example.com has a valid, active Postmark DKIM key configured — specifically look up the postmark selector and tell me the key type, length, and whether it's been revoked?","exampleUseCases":[{"title":"Verifying Postmark email deliverability setup","prompt":"We just set up Postmark for sending transactional emails from acme.com — can you check if the postmark DKIM selector is live and the key looks valid so we know mail will actually verify?"},{"title":"Auditing domain email security posture","prompt":"I need to audit the email authentication setup for startup.io — can you check if their Postmark DKIM selector is configured, what key type and length it uses, and whether the key is revoked or in test mode?"},{"title":"Diagnosing Postmark email signing failures","prompt":"Emails sent through Postmark from mycompany.com are failing DKIM verification — can you look up the postmark._domainkey DNS record and tell me if the key is missing, revoked, or has any obvious issues?"}],"resultDescription":"Returns parsed DKIM TXT record details for the postmark._domainkey.<domain> DNS entry, including: the v= (version) tag, k= (key type, e.g. RSA), the public key itself, key length in bits, whether the domain is in testing mode, and whether the key is revoked (empty p= field). Also confirms whether mail signed with the postmark selector will successfully verify.","failureModes":["Domain not found or has no DNS records — returns empty or NXDOMAIN result","No postmark._domainkey TXT record exists for the domain — indicates Postmark DKIM not configured","Revoked key detected (empty p= field) — key present but unusable for verification","DNS resolution failure via Cloudflare DoH — transient network error","Malformed TXT record that cannot be parsed — partial results returned","Payment failure for the $0.01 USDC x402 fee — request not processed"],"whenToPreferThis":"Use this endpoint when you specifically need to verify or inspect the Postmark DKIM selector for a domain. Prefer this over generic DKIM lookup tools when the sending provider is known to be Postmark, as it targets the exact selector name and parses Postmark-relevant key metadata. Choose this over manual DNS queries when you need structured, machine-readable output including key length and revocation status.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-20T00:59:29.361Z","isFirstParty":false,"canonicalSlug":"dkim-postmark-selector-lookup-45ffe821"}