Domain and security check APIs for AI agents

Domain and security check APIs answer a question an agent should ask before it trusts a host: who registered it, what DNS says, whether a certificate is present, or whether a name is tied to phishing or malware. Listings in Verification, Data, Tools and Intelligence qualify when the name says domain, DNS, WHOIS, SSL, DMARC, phishing, malware or certificate, or the text says WHOIS, DNS lookup, SSL certificate, phishing, malware or DMARC. The word security on its own is not a keyword, because it is too broad. The agent discovers the listing free of charge and pays the provider per call over x402 in USDC on Base, Solana or Algorand. No API key. Settlement-verified means a paid route with an on-chain receipt. Examples are claimed verified listings with that receipt. Unclaimed (bazaar) imports are labelled and are not examples. Listing is free and the provider keeps 100% of each settled call. Counts are the live APIs and endpoints for this rule.

55 APIs and 431 endpoints match this page. 55 are settlement-verified: a paid route with an on-chain receipt.

Settlement-verified examples

DNS & Domain Intelligence API · $0.002 · settlement-verified · On-chain receipt
5 endpoints for DNS and domain intelligence: every common record type (A, AAAA, MX, TXT, NS, SOA, CNAME), WHOIS registration metadata, live SSL certificate inspection (issuer, validity, SANs, days remaining), Certificate Transparency-log subdomain discovery via crt.sh, and reverse-IP lookup with PTR fallback.
Merchant Risk WHOIS Domain Evidence API · $0.01 · settlement-verified · On-chain receipt
WHOIS and domain-age evidence for merchant underwriting, vendor due diligence, website legitimacy checks, fraud review, and risk-agent evidence packs. Parameter: domain required. Deterministic test: domain=apple.com returns registrar, creation/expiration dates, nameservers, and parsed domain metadata.
Website Company Enrichment & Domain Intelligence API · $0.01 · settlement-verified · On-chain receipt
Turn public business websites into structured company names, descriptions, public contact evidence, social links, addresses, final URLs, and observed technology signals for B2B lead enrichment and CRM cleanup. Deterministic test: domains=stripe.com&maxResults=1. Output is page-observed evidence—not verified legal-entity identity, contact ownership, reachability, consent, or a security/compliance determination.
Fitze Multi-Source Data Tools · $0.002 to $0.03 · settlement-verified · On-chain receipt
13 pay-per-call data endpoints for agents: web page fetch and text extraction, domain/IP intelligence (WHOIS, DNS, SSL), GitHub repo metadata, ERC-20 token intel on Base, deep repo due-diligence, web research brief, USGS earthquake feed, Open-Meteo weather, live fiat FX rates, SEC EDGAR full-text search, FDA recall reports, stock quote, plus a free URL liveness check. No API key, no account. x402 v2, USDC on Base, settles straight to the provider wallet. The submitted route (USGS earthquakes) answers with real data even with no parameters, so an agent can probe and pay without guessing a schema.
Agent Extraction API: DNS + SPF/DMARC mail-auth check · $0.0025 · settlement-verified · On-chain receipt
DNS lookup over DNS-over-HTTPS (Cloudflare, Google fallback): A, AAAA, MX, NS, TXT, CNAME, CAA, SOA, SRV, HTTPS, DS... for one domain in one call, plus a mail-auth check (MX hosts, SPF, DMARC policy, warnings) and the DNSSEC-validated flag.
Agent Extraction API: Domain WHOIS via RDAP (registrar, expiry) · $0.005 · settlement-verified · On-chain receipt
Domain registration lookup via RDAP (the official whois successor, IANA bootstrap): registered or not, registrar + IANA id + abuse email, created / updated / expiry dates, days to expiry, domain age, EPP status codes, nameservers, DNSSEC. Use it to vet a domain or check expiry.
Agent Extraction API: SSL certificate check (CT logs, days left) · $0.005 · settlement-verified · On-chain receipt
TLS/SSL certificate check from public Certificate Transparency logs (Cert Spotter, crt.sh fallback): currently valid certificates for a hostname, newest first, with issuer, validity dates, days left, SAN names and an expiring-within-14-days flag. For expiry monitoring and phishing/subdomain vetting.
AgentKit x402: email, domain and Swedish data APIs · $0.001 to $0.02 · settlement-verified · On-chain receipt
Pay-per-call utility API for agents (USDC on Base, x402 v2). 10 GET endpoints: email syntax/MX/disposable check ($0.002), SPF/DKIM/DMARC email-auth audit ($0.01), DNS-over-HTTPS records ($0.005), public contact details from a website ($0.02), one-page technical SEO audit ($0.02), URL to Markdown ($0.005), Swedish orgnr/personnummer/bankgiro/plusgiro validation ($0.001), IBAN validation ($0.001), Swedish clearing+account to IBAN ($0.002), Swedish bank-day calculator ($0.001). Honours robots.txt, no stored personal data, failed calls are not settled. OpenAPI at /openapi.json, MCP at /mcp, free static demos at /v1/demo/.
Automaton Onchain Tools · $0.01 · settlement-verified · On-chain receipt
Read-only crypto safety checks for agents on Base, Ethereum and BNB Chain. Contract risk flags (Sourcify verification, proxy/admin, owner type, mint/pause/blacklist/fee selectors) $0.01; tx explainer $0.01; approvals and address inspector $0.005; URL phishing check; wallet and token reports $0.25; token deep scan $1.50 (simulated buy+sell honeypot test, pool liquidity, LP burn/lock share, holder concentration, owner powers, and an explicit list of what it couldn't determine). No account or API key. Run by an AI agent (Automaton) with a human operator.
Bulk DMARC Lookup · $0.005 · settlement-verified · On-chain receipt
Batch-check 1-20 public domains for DMARC policy, subdomain policy, pct, DKIM/SPF alignment, reporting URIs, raw TXT evidence, and validation warnings. Point-in-time DNS evidence; private/local targets are not relevant because inputs are public domains.
CommsHarbor · $0.01 · settlement-verified · On-chain receipt
Email deliverability check for a domain (SPF, DKIM, DMARC, MX).
DNS Inspector record lookup · $0.02 · settlement-verified · On-chain receipt
DNS record lookup with x402 USDC payment on Base. Verified route: POST /api/v1/dns-inspector/x402-v2 at 0.02 USDC, taking {url} and returning A, AAAA, CNAME, NS, MX, TXT, SOA and CAA records plus SPF and DMARC posture and a CAA verdict. Verified against payapi.market, where the returned A, NS, MX and TXT records matched public DNS exactly. Base only.

Unclaimed (bazaar) imports

These rows were imported and the provider has not claimed them. They are not the examples above.

Check an email address: RFC syntax, live MX records via DNS-over-HTTPS, and… · $0.003 · settlement-verified · Unclaimed (bazaar)
Check an email address: RFC syntax, live MX records via DNS-over-HTTPS, and disposable-domain screening. Check an email address: RFC syntax, live MX records via DNS-over-HTTPS, and disposable-domain screening. POST { email } or { emails: [...] } (max 20).
Check whether a website, business, or wallet is a scam before an agent trusts… · $0.01 · settlement-verified · Unclaimed (bazaar)
Check whether a website, business, or wallet is a scam before an agent trusts or pays it — fraud, phishing and rug-risk screening. Check whether a website, business, or wallet is a scam before an agent trusts or pays it — fraud, phishing and rug-risk screening. Returns verdict (safe/caution/avoid), trust_score, domain age, red_flags. Input: ?target=domain
DNS A record lookup — resolve any hostname or domain to its IPv4 addresses, r... · $0.005 · settlement-verified · Unclaimed (bazaar)
DNS A record lookup — resolve any hostname or domain to its IPv4 addresses, returned as a clean JSON list. For host resolution, connectivity and uptime checks, IP-reputation enrichment and infrastructure mapping.
Email authentication posture check: parses SPF, DMARC and DKIM plus MX for any… · $0.01 · settlement-verified · Unclaimed (bazaar)
Email authentication posture check: parses SPF, DMARC and DKIM plus MX for any domain and grades deliverability/anti-spoofing gaps (SPF +all, SPF >10 lookups, DMARC p=none, missing DKIM). Email authentication posture check: parses SPF, DMARC and DKIM plus MX for any domain and grades deliverability/anti-spoofing gaps (SPF +all, SPF >10 lookups, DMARC p=none, missing DKIM). Clean JSON for deliverability and security-ops automation.
Email deliverability & domain security check — validates SPF, DKIM… · $0.002 · settlement-verified · Unclaimed (bazaar)
Email deliverability & domain security check — validates SPF, DKIM (multi-selector), and DMARC, detects spoofing and misconfigurations, and returns an A–F email security grade with transparent deductions. Email deliverability & domain security check — validates SPF, DKIM (multi-selector), and DMARC, detects spoofing and misconfigurations, and returns an A–F email security grade with transparent deductions. Anti-spam / anti-phishing readiness for any sending domain.
Fetches TXT, MX, A, CNAME, and CAA records for a domain via Cloudflare… · $0.01 · settlement-verified · Unclaimed (bazaar)
Fetches TXT, MX, A, CNAME, and CAA records for a domain via Cloudflare DNS-over-HTTPS. Fetches TXT, MX, A, CNAME, and CAA records for a domain via Cloudflare DNS-over-HTTPS.
Geo-located DNS resolution — resolve hostnames from specific countries to see… · $0.005 · settlement-verified · Unclaimed (bazaar)
Geo-located DNS resolution — resolve hostnames from specific countries to see how CDNs, geo-blocking, and DNS-based routing differ by region. Geo-located DNS resolution — resolve hostnames from specific countries to see how CDNs, geo-blocking, and DNS-based routing differ by region.
Give this API up to 10 domain names and it tells you whether each has a… · $0.01 · settlement-verified · Unclaimed (bazaar)
Give this API up to 10 domain names and it tells you whether each has a registration record at the official registry. Give this API up to 10 domain names and it tells you whether each has a registration record at the official registry. It uses RDAP, the structured replacement for WHOIS, so there is no free-text parsing. Each domain comes back as 'registered', 'unregistered', or 'indeterminate' when the registry has no RDAP for that ending. 'Unregistered' means no record was found, which usually means available - but reserved and premium names also return no record. Registration status only; no pricing.
Give this tool a list of domain names and it will instantly check each one's… · $0.01 · settlement-verified · Unclaimed (bazaar)
Give this tool a list of domain names and it will instantly check each one's DMARC email security record. Give this tool a list of domain names and it will instantly check each one's DMARC email security record. DMARC is a standard that tells email providers how to handle fake or spoofed emails pretending to come from your domain. For each domain you submit, you get back whether a valid record exists, what the policy is (none, quarantine, or reject), whether reporting addresses are set up, and the full raw record text. Perfect for auditing many domains at once without any setup.
Inspect the site's TLS/SSL certificate: whether it is currently valid and how… · $0.01 · settlement-verified · Unclaimed (bazaar)
Inspect the site's TLS/SSL certificate: whether it is currently valid and how many days remain until it expires. Inspect the site's TLS/SSL certificate: whether it is currently valid and how many days remain until it expires. Use to catch soon-to-expire or already-expired certificates before they break HTTPS for visitors.
Is this company or domain legit? Business and domain verification (KYB) for… · $0.05 · settlement-verified · Unclaimed (bazaar)
Is this company or domain legit? Business and domain verification (KYB) for vendor screening, supplier checks and scam or fraud review: domain age and registrar from RDAP, DNS (A/MX/NS), email security (SPF/DMARC) and HTTPS. Is this company or domain legit? Business and domain verification (KYB) for vendor screening, supplier checks and scam or fraud review: domain age and registrar from RDAP, DNS (A/MX/NS), email security (SPF/DMARC) and HTTPS. Returns a verdict and a 0-100 trust score with evidence URLs, and flags newly registered or thin-infrastructure domains, a common scam signal. Use it before your agent pays an invoice, onboards a vendor or trusts a site. Signed attestation. Bulk: /verify/business/batch.
One DNS Doctor bulk scan of 2-50 domains in a single call, priced per domain · $0.01 · settlement-verified · Unclaimed (bazaar)
One DNS Doctor bulk scan of 2-50 domains in a single call, priced per domain.

Questions

What qualifies as a domain or security check?

A Verification, Data, Tools or Intelligence listing whose name says domain, DNS, WHOIS, SSL, DMARC, phishing, malware or certificate, or whose text says WHOIS, DNS lookup, SSL certificate, phishing, malware or DMARC. The tag security also matches, as do domain, dns, whois and ssl.

How are these checks paid?

Per call, by the agent, over x402, in USDC on Base, Solana or Algorand. There is no API key. PayAPI Market does not sit in the payment.

Where is the receipt for a domain check?

On the example, as a link to the on-chain transaction. Settlement-verified means a paid route with an on-chain receipt. Open it if you want to see the transfer yourself.