# Agent402 UK Email Syntax Validator

> Agent402 UK Email Syntax Validator is a paid API for AI agents from agent402.co.uk, paid per call via x402, $0.001/call, status down (last checked 2026-09-15).

Validates email address syntax (format only, no DNS/MX lookup) and returns the parsed domain and a boolean valid_syntax flag.

## Facts

- Endpoint: POST https://agent402.co.uk/v1/validate/email
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent402-uk-email-syntax-validator-5dec57ce
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_qJWxLozb0vig4dy5BRu2r

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-uk-email-syntax-validator-5dec57ce -d '<json body>'
```

Example prompt: Before writing this contact to the CRM, just do a quick syntax check on their email — is 'john.doe@example.com' a valid format, and what domain does it belong to?

## When to prefer this

Choose this endpoint when you need a fast, cheap, pure-logic email format check before a CRM write, database insert, or outreach step — and you do NOT need MX record verification or disposable-domain detection. At $0.001 per call it is ideal as a pre-filter before investing in more expensive DNS-based validation. Prefer this over LLM-based guessing or heavier validation services when format-only correctness is sufficient.

## Known failure modes

- Missing or empty 'email' field in request body returns an error
- Non-string input for email may cause a parsing error
- Payment failure (402) if x402 micropayment is not properly handled
- Network timeout if the service is temporarily unavailable

## How this service works

Don't burn tokens on deterministic work. Go/no-go jobs first: payout preflight, text firewall (PII/secrets), budget check — then rails, calendars, finmath. x402 USDC on Base. UK + global. agent402.co.uk — not agent402.tools. $0.001–$0.002 USDC on Base. No API keys.

## Output

Returns a JSON object with two fields: 'domain' (the domain part of the email address as a string, e.g. 'example.com') and 'valid_syntax' (a boolean indicating whether the email string is syntactically well-formed). No DNS, MX, or disposable-address checks are performed.

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "domain": "example.com",
  "valid_syntax": true
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent402-uk-email-syntax-validator-5dec57ce/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent402.co.uk](https://www.zero.xyz/host/agent402.co.uk/llms.txt)