# B2A Email Deliverability, MX, SPF & DMARC Verifier

> B2A Email Deliverability, MX, SPF & DMARC Verifier is a paid API for AI agents from mcp-security.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 domain detection, role account detection, and live DNS MX, SPF, and DMARC record checks to confirm deliverability.

## Facts

- Endpoint: GET https://mcp-security.agentdiet.dev/v1/email-check?utm_source=zero.xyz
- Price: $0.005/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: mcp-security.agentdiet.dev
- Website: https://mcp-security.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/mcp-security-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-f2241fd2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_xQPXE9bfk3lDys62kmsgp

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 mcp-security-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-f2241fd2
```

Example prompt: Can you check whether john.doe@tempmail.com is a real, deliverable email address — specifically whether it's from a disposable provider and whether the domain has valid MX, SPF, and DMARC records set up?

## When to prefer this

Choose this endpoint when you need a comprehensive, multi-signal email check in a single call — combining syntax, disposable detection, role-account flagging, and live DNS MX/SPF/DMARC verification. Prefer it over simple regex-only validators when deliverability accuracy matters, or over heavyweight email-sending APIs that charge per send just to test validity. Particularly well-suited for agentic workflows that need fast, cheap per-address checks at signup, lead enrichment, or outreach list qualification.

## Known failure modes

- Invalid or missing email parameter returns a 400 error
- DNS lookup timeouts for domains with unresponsive nameservers may return partial results
- Novel disposable providers not yet in the blocklist may not be flagged
- Payment not processed (402) if x402 micropayment header is missing or invalid
- Domains with no MX records correctly return non-deliverable but may surface false negatives for catch-all configs

## 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://mcp-security.agentdiet.dev/v1/email-check)

## Output

Returns a structured JSON object indicating whether the email passes syntax checks, whether the domain is a known disposable/burner provider, whether it is a role-based account (e.g. admin@, noreply@), and the live DNS lookup results for MX records, SPF record presence, and DMARC record presence — giving a comprehensive deliverability 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/mcp-security-agentdiet-dev-b2a-email-deliverability-mx-spf-dmarc-f2241fd2/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mcp-security.agentdiet.dev](https://www.zero.xyz/host/mcp-security.agentdiet.dev/llms.txt)