Email authentication posture

Endpoint

https://apiacre.com/v1/web/email-auth

Send the JSON body below. An unpaid request returns HTTP 402 with a PAYMENT-REQUIRED header; an x402-compatible buyer signs the requirement and retries with PAYMENT-SIGNATURE.

Official Coinbase agent path

Coinbase Agentic Wallet can satisfy this x402 request in one command. Running it may pay automatically, so --max-amount is fixed to $0.005 USDC in atomic units. Copying the command does not install, authenticate, sign, or pay; review the request and use a separate low-value wallet before running it.

npx --yes awal@latest x402 pay https://apiacre.com/v1/web/email-auth \
  -X POST \
  -d '{"domain":"apiacre.com","dkim_selectors":["protonmail"]}' \
  --max-amount 5000 \
  --json

Coinbase pay-for-service documentation · Buyer setup and wallet safety

npx --yes agentcash@latest check https://apiacre.com/v1/web/email-auth
npx --yes agentcash@latest fetch https://apiacre.com/v1/web/email-auth \
  --method POST \
  --header 'content-type: application/json' \
  --body '{"domain":"apiacre.com","dkim_selectors":["protonmail"]}' \
  --payment-protocol x402 \
  --payment-network base \
  --max-amount 0.005

Input example

{
  "domain": "apiacre.com",
  "dkim_selectors": [
    "protonmail"
  ]
}

Response shape

View free static sample JSON

{
  "request_id": "018f1f54-7f38-7ba2-8dc3-5f90272d9f1a",
  "service": "web.email-auth",
  "version": "1",
  "data": {
    "domain": "apiacre.com",
    "mailRouting": {
      "mode": "explicit_mx",
      "mxRecords": [
        "10 mail.protonmail.ch.",
        "20 mailsec.protonmail.ch."
      ],
      "nullMx": false,
      "addressFallbackObserved": true
    },
    "spf": {
      "configured": true,
      "recordCount": 1,
      "records": [
        "v=spf1 include:_spf.protonmail.ch ~all"
      ],
      "multipleRecords": false,
      "allQualifier": "softfail",
      "directDnsMechanismCount": 1
    },
    "dmarc": {
      "configured": true,
      "recordCount": 1,
      "records": [
        "v=DMARC1; p=quarantine"
      ],
      "multipleRecords": false,
      "policy": "quarantine",
      "subdomainPolicy": null,
      "percentage": null,
      "aggregateReportingConfigured": false,
      "forensicReportingConfigured": false,
      "dkimAlignment": null,
      "spfAlignment": null
    },
    "dkim": {
      "checked": true,
      "checkedSelectors": [
        "protonmail"
      ],
      "selectors": [
        {
          "selector": "protonmail",
          "configured": true,
          "recordCount": 1,
          "multipleRecords": false,
          "revoked": false,
          "keyType": "rsa",
          "publicKeySha256": "cc2f27246460f945974ac7bf0282287809d7f7c76757b4cdad5590fa38a80f69"
        }
      ],
      "reason": null
    },
    "optionalPolicies": {
      "mtaSts": {
        "configured": false,
        "recordCount": 0,
        "records": []
      },
      "tlsReporting": {
        "configured": false,
        "recordCount": 0,
        "records": []
      },
      "bimi": {
        "configured": false,
        "recordCount": 0,
        "records": []
      }
    },
    "posture": {
      "status": "enforcing",
      "basis": "published DNS records only"
    },
    "findings": [],
    "provenance": {
      "source": "recursive DNS",
      "queries": [
        "apiacre.com A",
        "apiacre.com AAAA",
        "apiacre.com MX",
        "apiacre.com TXT",
        "_dmarc.apiacre.com TXT",
        "protonmail._domainkey.apiacre.com TXT",
        "_mta-sts.apiacre.com TXT",
        "_smtp._tls.apiacre.com TXT",
        "default._bimi.apiacre.com TXT"
      ],
      "queryCount": 9
    },
    "limitations": [
      "DNS answers are a time-specific recursive-resolver snapshot and may be cached.",
      "DKIM is checked only for selectors explicitly supplied by the caller.",
      "Published records do not prove delivery, domain ownership, sender identity, or message authenticity."
    ],
    "checkedAt": "2026-08-12T18:03:16+00:00",
    "collectionMs": 19
  },
  "meta": {
    "duration_ms": 42,
    "cached": false,
    "sources": [],
    "warnings": [],
    "next_actions": []
  }
}

Try the payment challenge

curl -i -X POST 'https://apiacre.com/v1/web/email-auth' \
  -H 'content-type: application/json' \
  --data '{"domain":"apiacre.com","dkim_selectors":["protonmail"]}'