# Canonical URL Declarations — Term Context Excerpts

> Canonical URL Declarations — Term Context Excerpts is a paid API for AI agents from market.datapackvibe.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-17).

Parses a public webpage or supplied HTML to extract context excerpts surrounding occurrences of a specified term within canonical URL declarations.

## Facts

- Endpoint: POST https://market.datapackvibe.com/x402/assistant-bx-web-canonical-contexts?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-17
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/canonical-url-declarations-term-context-excerpts-192e3d4b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jgGGTdV7wTPTM7hdAqwFG

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-declarations-term-context-excerpts-192e3d4b -d '<json body>'
```

Example prompt: Parse the HTML at https://example.com/product-page and extract all context excerpts around the term 'product' found within canonical URL declarations, specifically looking at the id attribute for value 'main-canonical'.

## When to prefer this

Choose this endpoint when you need to specifically extract term-level context from canonical link declarations in HTML, particularly for SEO audits, duplicate content analysis, or verifying canonical tag correctness. It is ideal when you already have the HTML or a public URL and want targeted excerpts rather than a full-page scrape. It is not suitable for JavaScript-rendered pages, authenticated pages, or general full-text extraction tasks.

## Known failure modes

- URL is not publicly accessible or requires authentication — returns error or empty result
- HTML exceeds 100,000 character limit — input truncated or rejected
- Term not found in any canonical URL declaration — returns empty excerpts array
- JavaScript-rendered content not visible — static parser only sees server-rendered HTML
- Invalid attribute name pattern — rejected by schema validation
- URL resolves to non-HTML content (PDF, image) — parsing fails or yields no results

## How this service works

Canonical URL declarations — Term context excerpts: Term context excerpts for Canonical URL declarations. One public HTTPS page or supplied HTML; static parsing, no JavaScript rendering, login or access bypass. Specialised preset in a shared 50-profile, 20-operation engine. 0.01 USDC includes one bounded term context excerpts result.

## Output

Returns bounded context excerpts showing where and how the specified term appears within canonical URL declarations on the parsed page, including surrounding text snippets from matching HTML elements identified by the given attribute and attribute value.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "default": "",
   "maxLength": 2048
  },
  "html": {
   "type": "string",
   "default": "<!doctype html><html><head></head><body><link rel=\"canonical\" href=\"https://www.iana.org/help/example-domains\" id=\"sample\"></body></html>",
   "maxLength": 100000
  },
  "term": {
   "type": "string",
   "default": "product",
   "maxLength": 100,
   "minLength": 1
  },
  "attribute": {
   "type": "string",
   "default": "id",
   "pattern": "^[a-zA-Z][a-zA-Z0-9:_-]{0,49}$",
   "maxLength": 50
  },
  "previous_texts": {
   "type": "array",
   "items": {
    "type": "string",
    "default": "",
    "maxLength": 1000
   },
   "default": [
    "Older example"
   ],
   "maxItems": 200,
   "minItems": 0
  },
  "attribute_value": {
   "type": "string",
   "default": "sample",
   "maxLength": 200
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/canonical-url-declarations-term-context-excerpts-192e3d4b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from market.datapackvibe.com](https://www.zero.xyz/host/market.datapackvibe.com/llms.txt)