# Crawlspur Sitemap Self-Referencing Canonical Check

> Crawlspur Sitemap Self-Referencing Canonical Check is a paid API for AI agents from crawlspur.halowerk.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Checks whether a sitemap object has a self-referencing canonical address (i.e. the canonical URL points to itself).

## Facts

- Endpoint: POST https://crawlspur.halowerk.com/v1/pruef/crawlspur/canonical-selbst/sitemap
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/crawlspur-sitemap-self-referencing-canonical-check-5076cdf3
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yDil50ZEX_RsQ9MfVEiIy

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 crawlspur-sitemap-self-referencing-canonical-check-5076cdf3 -d '<json body>'
```

Example prompt: Check whether the sitemap at https://example.com/sitemap.xml has proper self-referencing canonical tags — I want to know if there are any canonical URL issues on those sitemap entries.

## When to prefer this

Use this endpoint specifically when you need to audit a sitemap object (sitemap.xml or sitemap index) for self-referencing canonical correctness. Prefer sibling endpoints for checking canonical tags on regular pages, news documents, or parameter URLs. This is ideal for automated SEO pipelines that verify sitemap integrity before or after site launches.

## Known failure modes

- Invalid or unreachable URL returns an error finding
- Non-public or private IP addresses are rejected
- Malformed URL input fails schema validation
- CSS selector matching no element may fall back to first match or return an error
- Sitemap URL that returns non-XML content may cause parse failure

## How this service works

Prüft am Objekt sitemap den Befund selbstreferenzierende kanonische Adresse.

## Output

Returns a structured finding indicating whether the sitemap object has a self-referencing canonical address, including details about the canonical URL found and whether it matches the page's own URL.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "ziel": {
   "oneOf": [
    {
     "type": "string",
     "maxLength": 2048,
     "minLength": 1,
     "description": "Öffentliche HTTP(S)-Adresse; bei DNS-Befunden Domain oder öffentliche IP."
    },
    {
     "type": "object",
     "required": [
      "adresse"
     ],
     "properties": {
      "adresse": {
       "type": "string",
       "maxLength": 2048,
       "minLength": 1
      },
      "selektor": {
       "type": "string",
       "maxLength": 240,
       "minLength": 1,
       "description": "CSS-Selektor: genau ein Objekt, sonst erster Treffer des Objektfilters."
      },
      "vergleich": {
       "type": "string",
       "maxLength": 2048,
       "description": "Öffentliche Vergleichsadresse für Link-, Sitemap- oder Sprachbefunde."
      },
      "user_agent": {
       "type": "string",
       "pattern": "^[A-Za-z0-9_-]{1,80}$"
      },
      "dkim_selektor": {
       "type": "string",
       "pattern": "^[A-Za-z0-9_-]{1,63}$"
      }
     },
     "additionalProperties": false
    }
   ]
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/crawlspur-sitemap-self-referencing-canonical-check-5076cdf3/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from crawlspur.halowerk.com](https://www.zero.xyz/host/crawlspur.halowerk.com/llms.txt)