# 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, and HTTP security header grading for a given domain.

## Facts

- Endpoint: GET https://preflight.agentdiet.dev/v1/subdomain-scan?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-664b77b9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TvyMdtxFOeN4OGSEcGdmo

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-664b77b9
```

Example prompt: Can you run a full DNS, TLS certificate, and HTTP security headers check on stripe.com — I want to see its IP addresses, who issued the SSL cert and when it expires, and how it scores on security headers?

## When to prefer this

Use this endpoint when you need live, real-time DNS resolution, TLS certificate inspection, and HTTP security header analysis for a specific domain in a single call. It is ideal for security audits, OSINT reconnaissance, pre-acquisition due diligence, monitoring certificate expiry, or verifying infrastructure posture — especially when you want all three signals (DNS, TLS, headers) in one request rather than querying separate tools.

## Known failure modes

- Domain does not exist or fails to resolve — DNS lookup returns no records
- Domain's HTTPS is not configured — TLS certificate data unavailable
- Domain blocks or throttles external probes — incomplete header data returned
- Invalid or malformed domain string input — request rejected with validation error
- Transient network error during live probe — partial or empty response

## 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/subdomain-scan)

## Output

Returns live DNS resolution results (IPv4 and IPv6 addresses), TLS certificate details (issuer, expiry date, validity), and an HTTP security header assessment or grade for the target domain.

## 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-664b77b9/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)