MailCheck API
Email and domain validation for agents by Rowan Vale (built with AI assistance). POST /v1/email-check validates up to 100 emails per call: syntax/normalization, MX via DoH, disposable-domain flag (9.9k CC0 list), role/free-provider flags, typo suggestion, verdict + score (no SMTP probing). POST /v1/domain-check audits up to 2 domains: MX/NS/TXT, SPF + DMARC parse, DKIM at 10 common selectors, RDAP (registrar, created, expiry, DNSSEC) and an A-F grade. $0.001 per item (quote scales with item count). GET also accepted. Free tier 50/day at /v1/free/*. Docs: /llms.txt, /openapi.json.
1 route settlement-verified · $0.001 USDC/request · 1 endpoint · Verification · base network · x402 protocol
Verified routes
POST /v1/email-check {"emails":["jane.doe@gmial.com"]}· $0.001 · 2026-10-26 · receipt
Other routes are unverified.
Networks: Base (settlement-verified)
Discovery is free. Agents search the catalogue here. Payment happens on the listing 402, not on PayAPI.
url https://payapi.market/mcpListing facts
- Provider
- ToolSchema Forge
- Hosted at
mailcheck.toolschemaforge.workers.dev- Category
- Verification
- Price
- $0.001 USDC per request
- Payment networks
- Base
- Settlement-verified
- 1 route, last checked 2026-10-26
- Listed on PayAPI Market
- 2026-10-26
Try MailCheck API
Call a verified route without paying first. The server should answer HTTP 402 Payment Required with the price, the USDC asset, the network and the wallet to pay. An x402 client pays that amount on Base and retries with the payment header.
curl -i -X POST "https://mailcheck.toolschemaforge.workers.dev/v1/email-check {"emails":["jane.doe@gmial.com"]}"About this API
MailCheck API is listed in the Verification category with pricing at $0.001 USDC/request. One route has been settlement-verified by PayAPI Market on 2026-10-26. View receipt on Basescan.
Payments settle on base in USDC via the x402 protocol. AI agents discover this API through the PayAPI Market MCP server and pay per request without API keys or accounts.
This API exposes 1 endpoint.
Questions about this API
What does MailCheck API do?
Email and domain validation for agents by Rowan Vale (built with AI assistance). POST /v1/email-check validates up to 100 emails per call: syntax/normalization, MX via DoH, disposable-domain flag (9.9k CC0 list), role/free-provider flags, typo suggestion, verdict + score (no SMTP probing). POST /v1/domain-check audits up to 2 domains: MX/NS/TXT, SPF + DMARC parse, DKIM at 10 common selectors, RDAP (registrar, created, expiry, DNSSEC) and an A-F grade. $0.001 per item (quote scales with item count). GET also accepted. Free tier 50/day at /v1/free/*. Docs: /llms.txt, /openapi.json. It is provided by ToolSchema Forge.
How much does MailCheck API cost?
MailCheck API is priced at $0.001 USDC per request, paid per call with no subscription. PayAPI Market paid 0.001 USDC for one call to /v1/email-check {"emails":["jane.doe@gmial.com"]} when it verified the listing. The exact amount for each call is in the HTTP 402 response before any money moves.
Do I need an API key or account to use MailCheck API?
No. MailCheck API uses the x402 protocol, so an agent pays per request in USDC on Base and gets the response, with no API key, account or signup.
Has MailCheck API been verified?
Yes, 1 route. PayAPI Market paid for a real call from its own wallet, received real data back and recorded the USDC settlement on-chain, most recently on 2026-10-26.
How does an AI agent find MailCheck API?
Through the free PayAPI Market MCP server at https://payapi.market/mcp, using search_apis or get_api, or over plain HTTP at https://payapi.market/agent/search. Discovery is free; the agent pays the provider directly on the listing's own 402.
More Verification APIs · Browse the marketplace · List your own API
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