# mailcheck.hugen.tokyo MX Record Lookup

> mailcheck.hugen.tokyo MX Record Lookup is a paid API for AI agents from mailcheck.hugen.tokyo, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Performs a DNS MX record lookup for a given domain and returns whether mail servers exist along with their hostnames sorted by priority.

## Facts

- Endpoint: GET https://mailcheck.hugen.tokyo/mailcheck/mx
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/mailcheck-hugen-tokyo-mx-record-lookup-0ab5f4b6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_j2A2JBXe9pz-ErCqAaM3l

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 mailcheck-hugen-tokyo-mx-record-lookup-0ab5f4b6
```

Example prompt: Can you look up the MX records for acme.com and tell me if it has mail servers configured and what their hostnames and priorities are?

## When to prefer this

Choose this endpoint when you need a lightweight, serverless DNS MX record check without configuring a local DNS library or resolver. Ideal for agents that need to verify email deliverability infrastructure for arbitrary domains across all TLDs (including ccTLDs and new gTLDs) as part of an automated workflow. Prefer this over full email validation endpoints when you specifically need raw MX record data (hostnames and priorities) rather than a composite validity score.

## Known failure modes

- Domain does not exist — no MX records returned, mail server existence flag is false
- Domain exists but has no MX records configured — flag false, empty hostname list
- Malformed or invalid domain input — likely returns an error or empty result
- Temporary DNS resolution failure — transient error, retry recommended
- Payment failure for x402 micropayment — call rejected before DNS lookup is performed

## How this service works

MX record lookup for any domain — returns whether mail servers exist and their hostnames sorted by priority. Verify email deliverability before sending. Supports all TLDs including ccTLDs and new gTLDs. No DNS library setup needed. Accepts USDC payments on Base and Solana

## Output

Returns a structured response indicating whether the domain has MX records, along with a list of mail server hostnames sorted by priority (lowest priority number = highest precedence). Allows the caller to determine if a domain can receive email without any local DNS library setup.

## Request schema (JSON Schema)

```json
{
 "properties": {
  "input": {
   "required": [
    "method"
   ]
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/mailcheck-hugen-tokyo-mx-record-lookup-0ab5f4b6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mailcheck.hugen.tokyo](https://www.zero.xyz/host/mailcheck.hugen.tokyo/llms.txt)