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x402-tollbooth Email Verifier
x402
x402-tollbooth Email Verifier is a paid API for AI agents from x402-tollbooth.onrender.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-10-11).
Validates up to 25 email addresses per call by checking syntax, domain MX/A records, disposable-domain status, and role-account flags — without SMTP mailbox probing.
Price / call$0.005
Success—
StatusUnknown
How this service works
Check whether email addresses are real and safe to send to. Verifies up to 25 addresses per call: syntax, domain MX/A record (including null-MX), disposable-domain, role-account, free-provider and typo checks. Does not perform SMTP/mailbox verification.
Output
Returns per-address validation results covering: syntax check pass/fail, domain MX record presence, domain A record presence, whether the domain is a known disposable/temporary email provider, and whether the address is a role account (e.g. admin@, info@, support@). Does not confirm whether a specific mailbox exists on the server.
Example use cases
Pre-send campaign list cleanup
“Before I send out this marketing email, can you validate these 20 subscriber addresses and tell me which ones have bad domains, are disposable, or are role accounts like info@ or noreply@?”
New user signup fraud detection
“We just got a batch of signups — can you check these email addresses for disposable domains and role-account patterns so we can flag suspicious registrations before they activate their accounts?”
CRM import quality check
“I'm about to import a CSV of 18 leads into our CRM. Can you verify that each email has valid syntax and a working domain with MX records, and flag any that look like throwaway addresses?”
Technical details
Endpoint
POSThttps://x402-tollbooth.onrender.com/api/verify?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need fast, lightweight bulk email validation (syntax + domain-level checks) without triggering SMTP connections or risking blacklisting. Ideal for pre-send list hygiene, fraud detection at signup, and CRM import validation where mailbox-level SMTP probing is unnecessary or prohibited. Best for batches up to 25 addresses per call at very low cost per check.
Side effects
- More than 25 emails submitted in a single call — batch exceeds the per-call limit
- Malformed JSON body or missing 'emails' array field — returns 400-level error
- Payment not attached or insufficient — x402 payment required error
- Domain DNS lookup timeout — may result in inconclusive MX/A record status
- Service cold-start latency on Render free tier — initial request may be slow
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| emails | array | Array of email address strings, max 25 per call. |
Tags
x402
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