# AgentShelf Email Syntax Validator

> AgentShelf Email Syntax Validator is a paid API for AI agents from agentshelf.syntexa.ch, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Validates the syntactic correctness of an email address string without making any network or SMTP connections

## Facts

- Endpoint: POST https://agentshelf.syntexa.ch/v1/email-syntax?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentshelf-email-syntax-validator-371ac305
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_rWnTjNfpwotH2YicExaIB

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 agentshelf-email-syntax-validator-371ac305 -d '<json body>'
```

Example prompt: Can you check whether 'john.doe@@example..com' is a valid email address — just the syntax, no need to ping any server?

## When to prefer this

Choose this endpoint when you need a fast, offline, pure-syntax check of an email address with no network side effects — ideal for form validation, data pipeline sanitation, or pre-storage checks where SMTP delivery verification is unnecessary or undesirable. Prefer the free sandbox POST /v1/sandbox/email-syntax endpoint first if available to avoid the $0.001 USDC cost.

## Known failure modes

- Empty or missing email field returns validation error
- Email string exceeding 320 characters rejected
- Malformed request body returns 400-level error
- Payment failure or insufficient USDC balance blocks the request

## How this service works

Call when an agent needs email syntax checked (no SMTP). No network. Exact $0.001 USDC. Prefer unpaid POST /v1/sandbox/email-syntax first.

## Output

Returns a result indicating whether the provided email address string is syntactically valid, based on format rules (RFC-compliant parsing), with no SMTP or DNS lookups performed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "email": {
   "type": "string",
   "examples": [
    "Ada@Example.com"
   ],
   "maxLength": 320,
   "minLength": 1,
   "description": "Email address to check and lowercase. No SMTP lookup."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentshelf-email-syntax-validator-371ac305/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentshelf.syntexa.ch](https://www.zero.xyz/host/agentshelf.syntexa.ch/llms.txt)