# Domain OSINT, TLS Certificate & Security Headers Recon

> Domain OSINT, TLS Certificate & Security Headers Recon is a paid API for AI agents from preflight.agentdiet.dev, paid per call via MPP, $0.01/call, status unknown (last checked 2026-10-21).

Performs live DNS resolution (IPv4/IPv6), TLS certificate inspection (issuer, expiry), and HTTP security header grading for a given domain.

## Facts

- Endpoint: GET https://preflight.agentdiet.dev/v1/asn-lookup?utm_source=zero.xyz
- Price: $0.01/call
- Payment: MPP
- Status: unknown
- Last checked: 2026-10-21
- Activations on Zero: 0
- Provider: preflight.agentdiet.dev
- Website: https://preflight.agentdiet.dev
- Canonical page: https://www.zero.xyz/c/preflight-agentdiet-dev-domain-osint-tls-certificate-security-headers-fbf41a02
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_PrXbkddcn_cX99nw9wjLr

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 preflight-agentdiet-dev-domain-osint-tls-certificate-security-headers-fbf41a02
```

Example prompt: Can you check the TLS certificate issuer and expiry, DNS resolution, and HTTP security grade for anthropic.com?

## When to prefer this

Choose this endpoint when you need a fast, single-call lookup combining DNS, TLS certificate, and HTTP security header intelligence for a domain — particularly useful for security vetting, OSINT investigations, vendor due diligence, or certificate expiry monitoring, without needing to stitch together separate DNS, certificate transparency, and header-scanning tools.

## Known failure modes

- Domain does not exist or fails DNS resolution — returns error or empty DNS result
- Domain is unreachable over HTTPS — TLS certificate data unavailable
- Domain has no IPv6 record — IPv6 field empty or null
- HTTP server does not respond — security headers grade cannot be computed
- Malformed or missing domain input — returns validation error

## How this service works

Inspects live IPv4/IPv6 DNS resolution, TLS certificate issuer/expiry, and HTTP security grade. (Live x402 v2, IETF MPP & MCP endpoint at https://preflight.agentdiet.dev/v1/asn-lookup)

## Output

Returns live DNS resolution results (IPv4 and IPv6 addresses), TLS certificate metadata (issuer name, expiry date), and an HTTP security headers grade reflecting the domain's overall security posture.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "domain"
 ],
 "properties": {
  "domain": {
   "type": "string",
   "minLength": 1,
   "description": "Target domain name (e.g. anthropic.com, openai.com) for DNS, TLS certificate, and security header OSINT"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/preflight-agentdiet-dev-domain-osint-tls-certificate-security-headers-fbf41a02/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from preflight.agentdiet.dev](https://www.zero.xyz/host/preflight.agentdiet.dev/llms.txt)