# Domain Trust Check (DNS, Email Auth, TLS, Headers)

> Domain Trust Check (DNS, Email Auth, TLS, Headers) is a paid API for AI agents from domain-check-production-6228.up.railway.app, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-17).

Performs live technical security checks on a domain including DNS records, SPF/DMARC email authentication, DNSSEC, TLS certificate validity, and HTTPS security headers, returning a risk flag list.

## Facts

- Endpoint: GET https://domain-check-production-6228.up.railway.app/v1/domain/check?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/domain-trust-check-dns-email-auth-tls-headers-aa80d79c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_J5Aoay19ZFj1hGDLqapKg

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 domain-trust-check-dns-email-auth-tls-headers-aa80d79c
```

Example prompt: Before I reply to this invoice from payments@acmecorp.io, can you run a full domain trust check on acmecorp.io — DNS resolution, MX records, SPF, DMARC, TLS certificate validity, and HSTS — and tell me if anything looks off?

## When to prefer this

Use this endpoint when an agent needs a live, real-time technical trust assessment of a domain before acting on an email, link, or supplier relationship — especially when you need all of DNS, email auth (SPF/DMARC), TLS certificate validity, and HTTPS headers checked in a single call. Prefer this over manual DNS lookups or separate TLS checkers when you want a consolidated risk flag list with no setup required. Best for pre-flight checks in automated supplier onboarding, phishing triage, or security compliance workflows.

## Known failure modes

- Domain does not resolve — resolves:false with empty DNS records
- Invalid domain format input — likely 4xx error or error status in response
- TLS check fails if port 443 is not open or certificate is expired — reflected in tls.valid:false
- DMARC or SPF absent — reflected as null/missing fields rather than a hard error
- Network timeout reaching the target domain — may return partial results or error status
- Railway hosting outage causing the service itself to be unavailable

## How this service works

Live technical checks of a domain, measured by us at request time: A/AAAA, NS, MX records, SPF and DMARC policies, DNSSEC presence (DS), CAA, TLS certificate issuer, validity dates and hostname match on port 443, and HTTPS security headers (HSTS, CSP, X-Frame-Options). Returns a simple risk flag list. Use when an agent must sanity-check a company's or vendor's domain before trusting an email, link or supplier: does it resolve, receive mail, publish SPF/DMARC, and serve a valid TLS certificate.

## Output

Returns a JSON object with: DNS resolution status (resolves boolean), MX records with priority, SPF record text, DMARC policy, TLS certificate details (issuer, valid_to date, hostname match, validity boolean), HTTPS security headers (HSTS, CSP, X-Frame-Options), DNSSEC/CAA presence, overall status field, and a flags array listing detected risk issues. An empty flags array indicates no issues found.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "domain"
     ],
     "properties": {
      "domain": {
       "type": "string",
       "description": "Domain name, e.g. example.com (no scheme or path)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "mx": [
   {
    "exchange": "mx.example.com",
    "priority": 10
   }
  ],
  "spf": "v=spf1 -all",
  "tls": {
   "valid": true,
   "issuer": "DigiCert",
   "valid_to": "2027-01-15",
   "hostname_match": true
  },
  "dmarc": {
   "policy": "reject"
  },
  "flags": [],
  "legal": {
   "terms": "https://domain-check-production-6228.up.railway.app/terms",
   "privacy": "https://domain-check-production-6228.up.railway.app/privacy"
  },
  "domain": "example.com",
  "status": "ok",
  "headers": {
   "hsts": true
  },
  "resolves": true,
  "use_when": "Use when an agent must sanity-check a company's or vendor's domain before trusting an email, link or supplier: does it resolve, receive mail, publish SPF/DMARC, and serve a valid TLS certificate."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/domain-trust-check-dns-email-auth-tls-headers-aa80d79c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from domain-check-production-6228.up.railway.app](https://www.zero.xyz/host/domain-check-production-6228.up.railway.app/llms.txt)