# Lookproof Mail Check

> Lookproof Mail Check is a paid API for AI agents from api.lookproof.dev, paid per call via x402, $0.03/call, status unknown (last checked 2026-10-31).

Returns a consolidated email authentication report for a domain covering MX, SPF, DMARC, and optionally DKIM records in a single API call.

## Facts

- Endpoint: GET https://api.lookproof.dev/v1/mail/check?utm_source=zero.xyz
- Price: $0.03/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/lookproof-mail-check-c166e5e4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_6tNDyZjp1L0Q-5Pe0mZ7d

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 lookproof-mail-check-c166e5e4
```

Example prompt: Can you run a full email authentication check on example.com, including DKIM for the selectors 'google' and 'selector1', and tell me if MX, SPF, and DMARC are properly set up?

## When to prefer this

Use this endpoint when you need a comprehensive email authentication overview in a single call instead of querying MX, SPF, DMARC, and DKIM separately. Ideal for deliverability audits, security posture checks, onboarding vendor domain validation, or diagnosing email routing issues. Prefer this over four separate DNS lookups when you want coded findings and an aggregated status rather than raw DNS answers.

## Known failure modes

- Domain does not exist — NXDOMAIN returned for the domain
- No MX records found — domain not configured to receive mail
- SPF or DMARC record missing — findings flagged with appropriate error codes
- DKIM selector not found — specific selector entries marked absent in results
- DNS resolution timeout — upstream resolver unreachable
- Invalid dkim_selectors parameter format — query rejected

## How this service works

Check SPF, DMARC, DKIM, MTA-STS, DNSSEC and more, with results that explain what was found and why. Free browser checks and a pay-per-request API with x402.

## Output

A single JSON report containing MX record details, the parsed SPF record, the DMARC policy and tags, DKIM public key information for each requested selector, coded diagnostic findings for each component, and an overall pass/fail/warning status for the domain's email authentication configuration.

## Request schema (JSON Schema)

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

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/lookproof-mail-check-c166e5e4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.lookproof.dev](https://www.zero.xyz/host/api.lookproof.dev/llms.txt)