# FreeTier Agent API — Email Domain Verification

> FreeTier Agent API — Email Domain Verification is a paid API for AI agents from freetier-agent-api.pages.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-18).

Checks an email address for syntax validity, MX records, disposable domain status, free-mail provider status, and overall deliverability risk

## Facts

- Endpoint: GET https://freetier-agent-api.pages.dev/api/email-verify?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-18
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/freetier-agent-api-email-domain-verification-a28948d0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OoTDB_tfelkkaJzYdCtu-

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 freetier-agent-api-email-domain-verification-a28948d0
```

Example prompt: Can you check whether jane.doe@example.com is a real, deliverable email address — specifically whether the domain has MX records, if it's disposable or a free-mail provider, and what the overall risk verdict is?

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call email risk assessment without a subscription — particularly useful for agents doing real-time sign-up validation, lead qualification, or mailing list hygiene. It combines syntax, MX, disposable, free-mail, and role-address checks in a single call, with no API key or account required, billed at $0.005 USDC via x402 on Base.

## Known failure modes

- Missing or malformed email query parameter returns an error
- Email with valid syntax but unresolvable domain returns has_mx:false and risky verdict
- Network or DNS lookup timeout may cause delayed or failed response
- Newly registered domains may not yet have MX records leading to false risky verdict
- Catch-all mail servers may cause MX checks to pass even for non-existent mailboxes

## How this service works

Pay-per-call data API for AI agents: AI model prices and cost calculator, 4,259 MCP servers, email domain checks, text-to-JSON extraction, country/holiday/currency lookup, page and link checks, page-to-markdown, 2,230 verified APIs. x402, USDC on Base, no signup. Sources cited in every response.

## Output

A JSON object containing: the normalized email and domain, a boolean for syntax validity, a boolean for MX record presence, a boolean for disposable domain, a boolean for free-mail provider, a boolean for role address (e.g. info@, support@), a verdict string (e.g. 'risky', 'safe'), and an array of human-readable reasons explaining the verdict.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "email"
     ],
     "properties": {
      "email": {
       "type": "string",
       "description": "one email address"
      }
     }
    }
   }
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "role": false,
  "email": "jane.doe@example.com",
  "domain": "example.com",
  "has_mx": false,
  "reasons": [
   "no MX records"
  ],
  "verdict": "risky",
  "free_mail": false,
  "syntax_ok": true,
  "disposable": false
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/freetier-agent-api-email-domain-verification-a28948d0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from freetier-agent-api.pages.dev](https://www.zero.xyz/host/freetier-agent-api.pages.dev/llms.txt)