# Delx Commerce — HTML Canonical Link Check

> Delx Commerce — HTML Canonical Link Check is a paid API for AI agents from commerce.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-01).

Verifies whether a document URL and its declared canonical URL match, returning a pass/fail result with evidence of the check.

## Facts

- Endpoint: POST https://commerce.delx.ai/api/v1/x402/html-canonical-link-check?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-commerce-html-canonical-link-check-66726246
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_CAPzdWon2A_XQCPR5nJ11

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 delx-commerce-html-canonical-link-check-66726246 -d '<json body>'
```

Example prompt: Can you check whether the canonical URL declared on https://example.com/blog/my-post actually matches the document URL https://example.com/blog/my-post, and tell me if they're consistent?

## When to prefer this

Choose this endpoint when you need a lightweight, verifiable, pay-per-call check of whether a page's declared canonical URL matches its document URL, without signup or subscription. It is ideal for agents running automated SEO audits, web reliability pipelines, or one-off canonical tag validations where privacy matters (no data retention, in-memory only) and cost predictability ($0.001 USDC per call) is important.

## Known failure modes

- Missing or malformed document_url or canonical_url fields returns a validation error
- URLs exceeding 8192 characters are rejected
- Network or parsing issues with the provided URLs may result in an error response
- Payment failure via x402 prevents the call from executing

## How this service works

Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.

## Output

Returns a JSON object with the two compared URLs (left: document URL, right: canonical URL), a boolean 'matched' flag, an overall status of 'pass' or 'fail', an operation identifier, and an evidence block containing whether input was retained (always false), the SHA256 hash of the input, and the count of external calls made (always 0), confirming fully in-memory processing.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "document_url": {
   "type": "string",
   "maxLength": 8192,
   "description": "Document URL supplied to Html Canonical Link Check; used only for this bounded calculation and processed in memory without retention."
  },
  "canonical_url": {
   "type": "string",
   "maxLength": 8192,
   "description": "Canonical URL supplied to Html Canonical Link Check; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "left": "https://example.com/page",
   "right": "https://example.com/page",
   "matched": true
  },
  "schema": "delx/util-html-canonical-link-check/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "592c02dfd1b6df477a94ca4c931b3a3f08c24e00f6ccaf91931c0bf89268d170",
   "external_calls": 0
  },
  "operation": "web_reliability:html_canonical_link_check"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-commerce-html-canonical-link-check-66726246/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from commerce.delx.ai](https://www.zero.xyz/host/commerce.delx.ai/llms.txt)