# B2A Email Deliverability, MX, SPF & DMARC Verifier

> B2A Email Deliverability, MX, SPF & DMARC Verifier is a paid API for AI agents from serp-extract.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 checks.

## Facts

- Endpoint: GET https://serp-extract.agentdiet.dev/v1/mx-deliverability-verifier?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: serp-extract.agentdiet.dev
- Website: https://serp-extract.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/serp-extract-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-0c4064af
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ajJKflF9aXHIr9ZPLjoer

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 serp-extract-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-0c4064af
```

Example prompt: Can you check whether john.doe@example.com is a real, deliverable email address — specifically whether it has valid MX records, passes SPF and DMARC checks, and isn't from a disposable or burner provider?

## When to prefer this

Choose this endpoint when you need a comprehensive, single-call email health check that combines syntax validation, live DNS MX/SPF/DMARC lookups, and disposable/role-account detection — especially in agent workflows requiring fraud screening, CRM enrichment, or pre-send deliverability audits. Prefer it over lightweight regex-only validators when real DNS verification matters.

## Known failure modes

- Missing or malformed email parameter returns a validation error
- DNS lookup timeouts may cause MX/SPF/DMARC checks to fail or return partial results
- Newly registered domains may lack MX/SPF/DMARC records causing false negatives
- Disposable provider database may not include all known throwaway services
- Payment failure (HTTP 402) if USDC balance is insufficient for the $0.005 per-call fee

## 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://serp-extract.agentdiet.dev/v1/mx-deliverability-verifier)

## Output

Returns a structured object indicating: email syntax validity, whether the domain is a known disposable/burner provider, whether the address is a role account (e.g. info@, admin@), live DNS MX record presence and details, SPF record existence and content, and DMARC policy record — giving a holistic deliverability 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"
  },
  "limit": {
   "type": "integer",
   "default": 20,
   "maximum": 100,
   "minimum": 1,
   "description": "Maximum number of items to return per page (1-100)"
  },
  "cursor": {
   "type": "string",
   "description": "Opaque pagination cursor for fetching the next page"
  }
 }
}
```

## Response schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/serp-extract-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-0c4064af/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from serp-extract.agentdiet.dev](https://www.zero.xyz/host/serp-extract.agentdiet.dev/llms.txt)