# B2A Email Deliverability, MX, SPF & DMARC Verifier

> B2A Email Deliverability, MX, SPF & DMARC Verifier is a paid API for AI agents from preflight.agentdiet.dev, paid per call via MPP, $0.005/call, status unknown (last checked 2026-10-21).

Validates an email address for syntax correctness, disposable/burner provider status, role account detection, and live DNS MX, SPF, and DMARC record presence.

## Facts

- Endpoint: GET https://preflight.agentdiet.dev/v1/mx-check?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: preflight.agentdiet.dev
- Website: https://preflight.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/preflight-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-verifier-3d758a13
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_bZ6cEFaVQQUp94sPZ-al-

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 preflight-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-verifier-3d758a13
```

Example prompt: Can you check whether john.doe@acmecorp.com is a real, deliverable email address — verify the syntax, look up live MX records, and flag it if it's a disposable or role account?

## When to prefer this

Choose this endpoint when you need a single API call that combines email syntax checking, disposable/burner provider detection, role account flagging, and live DNS record validation (MX, SPF, DMARC) in one pass. It is particularly well-suited for B2B lead enrichment pipelines, signup fraud prevention, and pre-send deliverability checks where DNS-level verification is required, not just format validation.

## Known failure modes

- Malformed or missing email parameter returns a validation error
- DNS timeout or unreachable nameservers may result in incomplete MX/SPF/DMARC results
- Newly registered domains may have no DNS records yet, causing false negatives
- Disposable provider lists may lag behind newly created burner services
- Payment failure via x402 returns HTTP 402 before the check is performed

## How this service works

Validates email syntax, disposable/burner provider status, role accounts, and live DNS MX/SPF/DMARC records. (Live x402 v2, IETF MPP & MCP endpoint at https://preflight.agentdiet.dev/v1/mx-check)

## Output

Returns an object containing email syntax validity, whether the provider is a known disposable or burner service, whether the address appears to be a role account (e.g. admin@, support@), and live DNS lookup results for MX, SPF, and DMARC records on the email's domain — together providing a comprehensive deliverability and risk assessment.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "email"
 ],
 "properties": {
  "email": {
   "type": "string",
   "minLength": 1,
   "description": "Email address to validate for syntax, MX deliverability, and disposable risk"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/preflight-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-verifier-3d758a13/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from preflight.agentdiet.dev](https://www.zero.xyz/host/preflight.agentdiet.dev/llms.txt)