# agent402.tools Email Validator

> agent402.tools Email Validator is a paid API for AI agents from agent402.tools, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Validates an email address by checking syntax correctness and performing a live MX record DNS lookup on the domain to assess deliverability.

## Facts

- Endpoint: POST https://agent402.tools/api/email-validate
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent402-tools-email-validator-ade398a2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_MReb578E2JP4fl-BLzyeF

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability agent402-tools-email-validator-ade398a2 -d '<json body>'
```

Example prompt: Can you check whether 'john.doe@example.com' is a valid email address — look at the syntax and verify the domain actually has mail servers set up?

## When to prefer this

Use this endpoint when you need a quick, lightweight email validation that goes beyond simple regex — specifically when you want to confirm a domain can actually receive mail via MX record lookup. Prefer this over pure client-side regex validation when deliverability assurance matters, and over full send-based verification when you don't want to send a real email.

## Known failure modes

- DNS timeout causing MX lookup to fail or return inconclusive result
- Malformed input (non-string or missing email field) returning a 400 error
- Domain exists but has no MX records, returning a negative deliverability signal
- Network issues causing the live DNS lookup to be unavailable
- Payment failure due to insufficient USDC balance returning a 402 error

## How this service works

Validate an email address: syntax check plus live MX record lookup on the domain (deliverability signal, not a guarantee).

## Output

Returns a validation result indicating whether the email passes syntax checks and whether the domain has valid MX records, providing a deliverability signal (not a delivery guarantee).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "email": {
   "type": "string",
   "description": "Email address to check"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "email": "someone@gmail.com",
  "domain": "gmail.com",
  "mxRecords": [
   "gmail-smtp-in.l.google.com",
   "alt1.gmail-smtp-in.l.google.com"
  ],
  "syntaxValid": true,
  "deliverableDomain": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent402-tools-email-validator-ade398a2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent402.tools](https://www.zero.xyz/host/agent402.tools/llms.txt)