# Stride20k Email Validation

> Stride20k Email Validation is a paid API for AI agents from gateway.stride20k.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Validates an email address by checking RFC syntax and performing live MX-record DNS lookup to determine deliverability

## Facts

- Endpoint: GET https://gateway.stride20k.com/email/validate/%7Bemail%7D
- 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/stride20k-email-validation-e2400b22
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UKSPxnNgROuXVkWqHPEvT

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 stride20k-email-validation-e2400b22
```

Example prompt: Can you check whether hello@acme.io is a valid, deliverable email address — verify the syntax and look up its MX records?

## When to prefer this

Choose this endpoint when you need a lightweight, pay-per-call email validation with both RFC syntax checking and live DNS MX-record resolution in a single call, with no API key or account setup. Prefer it over heavyweight email verification services when you want schema-stable JSON output and per-call USDC micropayment billing via x402. Best for agents that need on-demand validation of individual email addresses during onboarding flows, lead enrichment, or pre-send hygiene checks.

## Known failure modes

- Malformed or missing email parameter returns error
- Domain with no MX or A records returns hasMx:false and deliverable:false
- DNS resolution timeout from Cloudflare DoH yields fetch error
- Syntactically invalid email short-circuits before DNS lookup
- Cached results may not reflect very recent DNS changes (meta.cached:true)

## How this service works

Agent data gateway plus the live x402 market feed. Normalized, schema-stable JSON for crypto prices, DeFi TVL, on-chain DEX pools, gas, FX, US Treasury yields, US weather, WHOIS, DNS, email validation, web-page extraction, tech news, Wikipedia, npm/PyPI package health, ERC-20 token-risk scoring, and composed domain dossiers, plus x402 ecosystem analytics and metered LLM inference. Pay per call with USDC via the x402 protocol; no accounts, no API keys.

## Output

Returns a JSON object containing: whether the email syntax is valid (syntaxValid), whether MX records exist (hasMx), an array of MX records with exchange hostname and preference values, whether an A-record fallback applies (aFallback), whether the address appears deliverable (deliverable), the parsed domain, the original email, and metadata including cache status, data source, and fetch timestamp.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "properties": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "data": {
   "mx": [
    {
     "exchange": "mail.example.com",
     "preference": 10
    }
   ],
   "email": "postmaster@example.com",
   "hasMx": true,
   "domain": "example.com",
   "aFallback": false,
   "deliverable": true,
   "syntaxValid": true
  },
  "meta": {
   "cached": false,
   "source": "local + Cloudflare DoH",
   "fetchedAt": "2026-07-04T00:00:00.000Z",
   "attribution": null
  },
  "endpoint": "/email/validate/:email"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/stride20k-email-validation-e2400b22/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from gateway.stride20k.com](https://www.zero.xyz/host/gateway.stride20k.com/llms.txt)