# SiteSignal Public HTTP Redirect Chain Snapshot

> SiteSignal Public HTTP Redirect Chain Snapshot is a paid API for AI agents from trinity-throw-thursday-gravity.trycloudflare.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-15).

Traces up to three HTTP redirects for a given URL and reports status codes, cross-origin hops, HTTPS downgrade warnings, and final response evidence.

## Facts

- Endpoint: GET https://trinity-throw-thursday-gravity.trycloudflare.com/x402/redirect-chain
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/sitesignal-public-http-redirect-chain-snapshot-207d347e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_KOzGVaPsrHWH0Eov07nhb

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 sitesignal-public-http-redirect-chain-snapshot-207d347e
```

Example prompt: Can you trace the redirect chain for https://example.com/old-page and tell me whether it stays on HTTPS the whole way, how many hops there are, and what the final destination URL is?

## When to prefer this

Use this endpoint when you need to programmatically audit redirect behavior for a single public URL — especially to detect HTTPS downgrades, cross-origin hops, or unexpected redirect destinations. It is ideal for SEO audits, link verification before publishing, and security checks on third-party URLs. Prefer this over a full crawler when you only need redirect-chain semantics (not full page content) and want lightweight, pay-per-call pricing at $0.02 USDC.

## Known failure modes

- URL is unreachable or DNS fails — returns error indicating connectivity issue
- URL does not redirect at all — returns single-hop result with no redirect chain
- More than three redirects present — only the first three hops are traced and reported
- Private/internal URLs or localhost addresses rejected — endpoint only handles public HTTP(S) URLs
- Malformed URL input — schema validation error returned before any request is made

## How this service works

Trace up to three public HTTP redirects and report status semantics, cross-origin hops, HTTPS downgrades, and final-response evidence.

## Output

Returns a structured breakdown of up to three redirect hops including HTTP status codes at each step, whether any hop crosses to a different origin (domain), whether any hop downgrades from HTTPS to HTTP, and the final response URL and status as evidence of the chain's endpoint.

## 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": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri",
       "description": "Public HTTP(S) URL to trace."
      }
     }
    }
   },
   "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/sitesignal-public-http-redirect-chain-snapshot-207d347e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from trinity-throw-thursday-gravity.trycloudflare.com](https://www.zero.xyz/host/trinity-throw-thursday-gravity.trycloudflare.com/llms.txt)