# HSTS Preload Check

> HSTS Preload Check is a paid API for AI agents from intel.rallylive.ca, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Checks a domain's Strict-Transport-Security header configuration and its status on the Chrome HSTS preload list via hstspreload.org

## Facts

- Endpoint: GET https://intel.rallylive.ca/site/hsts-preload
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/hsts-preload-check-28b087b0
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_K-Wd_BAI82Eg-0K017PB-

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 hsts-preload-check-28b087b0
```

Example prompt: Can you check if example.com has a valid HSTS header with the preload directive and whether it's already listed on the Chrome HSTS preload list?

## When to prefer this

Use this endpoint when you need to specifically audit HSTS header configuration and preload list status for a domain, especially before submitting to the Chrome HSTS preload list or performing a web security compliance check. It combines header inspection with live preload list lookup in a single call, making it more targeted than a generic SSL or HTTP header checker.

## Known failure modes

- Domain does not exist or is unreachable — no header data returned
- Site does not serve HTTPS — HSTS header absent
- Malformed domain input — validation error
- HSTS header present but missing required directives (e.g. no preload) — partial result with eligibility failure
- Rate limiting or payment failure — 402 or 429 response

## How this service works

HSTS check: the Strict-Transport-Security header on the site (max-age, includeSubDomains, preload), whether it meets Chrome preload-list requirements, and the domain's current status in the HSTS preload list (hstspreload.org). Transport security hardening. $0.01 per domain.

## Output

Returns the Strict-Transport-Security header value from the target domain including max-age duration, whether includeSubDomains and preload directives are present, whether the configuration meets Chrome HSTS preload list requirements, and the domain's current status in the hstspreload.org preload list.

## 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",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/hsts-preload-check-28b087b0/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from intel.rallylive.ca](https://www.zero.xyz/host/intel.rallylive.ca/llms.txt)