# Canonical URL Check

> Canonical URL 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 web page's rel=canonical tag, whether it is self-referencing, absolute, on the same host, the final URL after redirects, and noindex status to catch duplicate-content and indexing mistakes.

## Facts

- Endpoint: GET https://intel.rallylive.ca/site/canonical
- 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/canonical-url-check-94d44613
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UM-2h0rn_QRZpNwbOClun

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 canonical-url-check-94d44613
```

Example prompt: Can you check the canonical tag for https://example.com/blog/my-post — I want to know if it's self-referencing, whether it's an absolute URL on the same host, what the final URL is after redirects, and whether the page is set to noindex?

## When to prefer this

Choose this endpoint when you need to specifically audit the canonical tag configuration, noindex status, and redirect chain of a single page for SEO health — especially when diagnosing duplicate content issues, verifying indexability, or checking canonical correctness during a site audit. Prefer this over a general webpage metadata extractor when the canonical/redirect/noindex combination is the primary focus.

## Known failure modes

- Page URL is unreachable or returns a non-200 status — endpoint may return an error or partial data
- Page has no canonical tag — result will indicate absence of canonical
- Redirect loop or excessive redirects may cause timeout or failure
- Invalid or malformed URL input may result in a validation error
- Paywalled or JavaScript-rendered pages may not expose canonical tags correctly

## How this service works

Canonical URL check: the rel=canonical of a page, whether it is self-referencing, absolute and on the same host, the final URL after redirects, and whether the page is set noindex. Catch duplicate-content and indexing mistakes. $0.01 per page.

## Output

Returns the rel=canonical URL found on the page, a flag indicating whether it is self-referencing, whether it is an absolute URL, whether it is on the same host as the page, the final URL after any redirect chain, and whether the page is marked noindex.

## 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/canonical-url-check-94d44613/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)