# Email Verification & MX Validation API

> Email Verification & MX Validation API is a paid API for AI agents from x402-datashop-production.up.railway.app, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Validates an email address via RFC 5322 syntax check and live MX record lookup, returning a deliverability verdict (deliverable, risky, or undeliverable) with DNS details.

## Facts

- Endpoint: GET https://x402-datashop-production.up.railway.app/v1/validate/email
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/email-verification-mx-validation-api-d2daddf1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_65Cs84s--uzCj1IgCWNZM

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 email-verification-mx-validation-api-d2daddf1
```

Example prompt: Can you check whether john.smith@acmecorp.io is a real, deliverable email address — run the full syntax and MX lookup and tell me if it's deliverable, risky, or undeliverable?

## When to prefer this

Use this endpoint when you need a fast, single-call email validation that goes beyond syntax checking to confirm actual DNS-level deliverability — ideal for lead qualification, sign-up form validation, or list hygiene where you want to detect NXDOMAIN domains and null-MX domains without running your own DNS infrastructure.

## Known failure modes

- Email address missing or malformed query parameter returns an error
- Domain has no MX records but is not NXDOMAIN — classified as risky
- DNS-over-HTTPS upstream failure may cause lookup errors
- Addresses over 254 characters are rejected
- Temporary DNS timeouts may return inconclusive results

## How this service works

One-call email verification for lead qualification and list hygiene: RFC 5322 syntax check, then a live MX lookup over DNS-over-HTTPS (Cloudflare, Google fallback). Detects non-existent domains (NXDOMAIN), null-MX domains that refuse mail (RFC 7505), and returns prioritized MX hosts. Query: ?email=someone@example.com. Verdict: deliverable | risky | undeliverable. 1h cache per address.

## Output

Returns a verdict of 'deliverable', 'risky', or 'undeliverable', along with prioritized MX host records, NXDOMAIN detection, null-MX (RFC 7505) flag, and syntax validity. Results are cached per address for 1 hour.

## Request schema (JSON Schema)

```json
{
 "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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "email"
     ],
     "properties": {
      "email": {
       "type": "string",
       "description": "Email address to verify (max 254 chars)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/email-verification-mx-validation-api-d2daddf1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-datashop-production.up.railway.app](https://www.zero.xyz/host/x402-datashop-production.up.railway.app/llms.txt)