# Extract Definition Lists as JSON – Change Watch

> Extract Definition Lists as JSON – Change Watch is a paid API for AI agents from page.intel.rallylive.ca, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-20).

Monitors a web page's definition lists (extracted as JSON) for changes, returning a diff of before/after values and a changed flag compared to the previous call.

## Facts

- Endpoint: GET https://page.intel.rallylive.ca/watch/page/definition-lists/json?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-20
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/extract-definition-lists-as-json-change-watch-4bc69b53
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_d5_eu2_Y9M4LvlUOui2CE

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 extract-definition-lists-as-json-change-watch-4bc69b53
```

Example prompt: Keep an eye on that product specs page for me — specifically the definition lists — and let me know if anything changes compared to the last time you checked it.

## When to prefer this

Choose this endpoint when you need to detect changes in definition list content on a web page over time, especially when you want a structured diff showing exactly which fields changed and what their previous values were. Prefer this over a plain extraction endpoint when your goal is change alerting or audit trailing rather than one-time data retrieval.

## Known failure modes

- Target URL is unreachable or returns a non-200 response, resulting in an error
- No previous snapshot exists (first call), so 'changed' is false or undefined with no diff
- Definition lists are rendered via JavaScript and not present in raw HTML, resulting in empty extraction
- Page blocks scraping (e.g. CAPTCHA, bot detection), causing extraction failure
- Snapshot older than 90 days has been purged, losing the comparison baseline

## How this service works

Change watch for extract definition lists as json: runs the check, compares it with the result from your previous call for the same url (kept 90 days) and returns the current answer, changed true/false, the fields that changed with before/after values, and when it was last seen. Schedule it to be alerted when this changes. $0.02 per check.

## Output

Returns the current definition lists extracted as JSON from the target page, a boolean 'changed' flag indicating whether they differ from the previous call, a list of the specific fields that changed with their before and after values, and a timestamp of when the page was last seen. The snapshot is retained for 90 days.

## 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/extract-definition-lists-as-json-change-watch-4bc69b53/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from page.intel.rallylive.ca](https://www.zero.xyz/host/page.intel.rallylive.ca/llms.txt)