# page-diff-watch

> page-diff-watch is a paid API for AI agents from intel.rallylive.ca, paid per call via x402, $0.02/call, status unknown (last checked 2026-09-14).

Monitors a webpage's text content and returns whether it changed since your last call, with before/after field diffs, using persistent 90-day result history.

## Facts

- Endpoint: GET https://intel.rallylive.ca/watch/page/text-diff
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/page-diff-watch-0ed931f8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_yq54NVD1de_2HmPnFg-8A

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 page-diff-watch-0ed931f8
```

Example prompt: Keep an eye on https://example.com/pricing for me — call it on a schedule and let me know the moment the page text changes, showing me exactly what was different before and after.

## When to prefer this

Choose this endpoint when you need persistent, stateful change detection for a webpage's text content across multiple calls over time — especially when you want to know exactly which fields changed and their before/after values without managing your own storage. Ideal for scheduled agent workflows that need to track page updates without maintaining a separate database of previous states. Prefer it over one-shot scraping tools when continuity and delta detection are the goal.

## Known failure modes

- URL is unreachable or returns a non-200 status, resulting in an error or no diff data
- First-time call for a URL has no previous result to compare against, so 'changed' may be indeterminate
- Page uses JavaScript rendering that is not captured by a plain HTTP GET, leading to incomplete text extraction
- 90-day history expiry means old baselines are lost and change detection resets
- Rate limiting or payment failures (x402) blocking repeated polling

## How this service works

Change watch for page diff: runs the check and compares it with the result from your previous call for the same url (kept 90 days), returning the current answer, changed true/false, exactly which fields changed with before/after values, and when it was last seen. Call it on a schedule to be told when page text diff against your previous call changes. $0.01 per check.

## Output

Returns the current page text result, a boolean 'changed' flag indicating whether content differs from the previous call for that URL, a list of exactly which fields changed with before and after values, and a timestamp of when the page was last seen. Results are retained for 90 days per URL.

## 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/page-diff-watch-0ed931f8/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)