# Saylor Innovations Email Authentication Posture Checker

> Saylor Innovations Email Authentication Posture Checker is a paid API for AI agents from saylorinnovations.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-28).

Returns a comprehensive email authentication analysis for a domain, including SPF lookup count, DMARC policy, DKIM selectors, MX records, MTA-STS, TLS-RPT, and BIMI status with prioritised issues

## Facts

- Endpoint: GET https://saylorinnovations.com/api/email/auth?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/saylor-innovations-email-authentication-posture-checker-5ca20611
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_FDtaGUERL8MU3n-isPKD0

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 saylor-innovations-email-authentication-posture-checker-5ca20611
```

Example prompt: Can you check the full email authentication posture for example.com — I want to see the SPF lookup count, DMARC policy, DKIM selectors, MX records, and any prioritised issues I should fix?

## When to prefer this

Choose this endpoint when you need a single-call, comprehensive email authentication audit covering SPF, DMARC, DKIM, MX, MTA-STS, TLS-RPT, and BIMI together with prioritised remediation issues. Prefer it over generic DNS lookup tools when you want pre-parsed, structured email security posture data with actionable issue rankings rather than raw DNS responses.

## Known failure modes

- Domain does not exist or is unresolvable — returns null or empty results for DNS records
- Domain has no SPF or DMARC record published — fields returned as null with appropriate notes
- DNS lookup timeout or transient failure — may return partial results
- Invalid domain format provided — likely returns error or empty response
- DNS lookup limit exceeded for SPF — flagged in dns_lookup_terms field

## How this service works

Email authentication posture for a domain - SPF with lookup count, DMARC policy and reporting, DKIM selectors, MX, MTA-STS, TLS-RPT and BIMI with prioritised issues

## Output

A JSON object containing: domain verdict and notes; SPF record text with parsed mechanisms, all-qualifier policy, included domains, and DNS lookup term count; DMARC policy with aggregate/forensic report addresses, policy level (none/quarantine/reject), percentage applied, and SPF/DKIM alignment modes; DKIM selectors found; MX records with hostnames and priority values; MTA-STS and TLS-RPT configuration; BIMI presence flag; and a prioritised list of issues to remediate.

## 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",
    "queryParams"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "POST",
      "PUT",
      "PATCH",
      "DELETE",
      "HEAD"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "domain"
     ],
     "properties": {
      "domain": {
       "type": "string",
       "description": "Sending domain such as example.com"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    },
    "example": {
     "type": "object",
     "required": [
      "domain",
      "verdict",
      "issues"
     ],
     "properties": {
      "mx": {
       "type": "array",
       "items": {
        "type": "object",
        "properties": {
         "priority": {
          "description": "MX preference; lower values are tried first"
         }
        }
       },
       "description": "Mail exchangers with priority and host"
      },
      "spf": {
       "type": [
        "object",
        "null"
       ],
       "properties": {
        "all": {
         "description": "The all qualifier: - fail, ~ softfail, ? neutral, + pass"
        },
        "record": {
         "description": "The SPF TXT record"
        },
        "includes": {
         "description": "Domains included by the record"
        }
       },
       "description": "SPF record text with parsed mechanisms and the all-qualifier policy"
      },
      "bimi": {
       "type": "boolean",
       "description": "True when a BIMI record is published"
      },
      "note": {
       "type": "string",
       "description": "Caveat or context for reading the result"
      },
      "dmarc": {
       "type": [
        "object",
        "null"
       ],
       "properties": {
        "rua": {
         "description": "Address for aggregate reports"
        },
        "ruf": {
         "description": "Address for forensic reports"
        },
        "policy": {
         "description": "DMARC policy: none, quarantine or reject"
        },
        "percent": {
         "description": "Percentage of mail the policy applies to"
     
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/saylor-innovations-email-authentication-posture-checker-5ca20611/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from saylorinnovations.com](https://www.zero.xyz/host/saylorinnovations.com/llms.txt)