# Email Verifier & Validator

> Email Verifier & Validator is a paid API for AI agents from email-verifier.underscoredone.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Verifies whether a single email address can actually receive mail and returns a valid/invalid/risky verdict with metadata about the address.

## Facts

- Endpoint: POST https://email-verifier.underscoredone.com/verify
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/email-verifier-validator-95fafc00
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jbzfBIt-Ues2iqDYWuRxJ

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-verifier-validator-95fafc00 -d '<json body>'
```

Example prompt: Can you check whether john.doe@company.com can actually receive emails — I want to know if it's valid, risky, or invalid, and whether it's a free provider or a role address?

## When to prefer this

Choose this endpoint when you need a single-address, real-time deliverability verdict with enrichment metadata (free provider and role account flags) in one call. Ideal for pre-send list hygiene, signup form validation, or CRM lead enrichment where you need more than just syntax checking. Not suited for bulk batch processing of large lists in a single call.

## Known failure modes

- Email address exceeds 320 characters — request rejected
- Malformed or non-string email input — validation error returned
- Unresolvable or nonexistent domain — may return invalid verdict
- Temporary DNS or SMTP timeout — may return risky or error response
- Payment not included or insufficient — 402 Payment Required response

## How this service works

Takes one email address and tells you whether it can actually receive mail. Returns a verdict of valid, invalid, or risky, splits the address into username and domain, and flags free providers and role accounts like admin@ or support@. One address per call.

## Output

Returns a JSON object with an overall verdict (valid, invalid, or risky), the email split into username and domain parts, a flag indicating whether the domain belongs to a free email provider (e.g. Gmail, Yahoo), and a flag indicating whether the address is a role account (e.g. admin@, support@, info@).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "email": {
   "type": "string",
   "description": "The single email address to check, such as alpha@gmail.com. Maximum 320 characters."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "api_version": "1.0.0"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/email-verifier-validator-95fafc00/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from email-verifier.underscoredone.com](https://www.zero.xyz/host/email-verifier.underscoredone.com/llms.txt)