# URL Change Detection - Website Change Monitoring

> URL Change Detection - Website Change Monitoring is a paid API for AI agents from scanpay-edge.alextaghiashvili.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-11-01).

Checks whether a public URL's readable content has changed since the last check, returning a changed flag and content hashes.

## Facts

- Endpoint: GET https://scanpay-edge.alextaghiashvili.workers.dev/api/v1/urlwatch?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/url-change-detection-website-change-monitoring-b1ba4dba
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Tcpx93a3Im7PpTUh3O1Uo

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 url-change-detection-website-change-monitoring-b1ba4dba
```

Example prompt: Can you check whether the content at https://example.com/pricing has changed since the last time we looked at it, and tell me if anything is different?

## When to prefer this

Choose this endpoint when you need lightweight, hash-based change detection for a public URL without storing or retrieving full page content. It's ideal for polling workflows where you want a fast yes/no answer on whether a page changed, rather than extracting or analyzing the full text. Prefer it over full page-extract endpoints when you only need to know IF something changed, not WHAT changed.

## Known failure modes

- URL is unreachable or returns a non-200 status — ok may be false or error returned
- URL has never been checked before — first_seen will be true and no previous_hash available
- URL content is dynamic/JavaScript-rendered and readable text may not reflect visual changes
- Rate limiting or network timeouts from the target server
- Invalid URL format provided in the request

## How this service works

Detect page changes with urlwatch - page change detection / website change monitoring / webpage diff: check whether a public URL's readable content changed since the last check; returns changed/first_seen plus content hashes. Use it to monitor a page for changes.

## Output

Returns a JSON object with: ok (boolean), the monitored URL, total check count, a changed boolean indicating if content differs from last check, a first_seen boolean for new URLs, the current content hash, and the previous content hash for comparison.

## 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",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "format": "uri"
      },
      "state_key": {
       "type": "string"
      },
      "previous_hash": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "url": "https://example.com/pricing",
  "checks": 4,
  "changed": true,
  "first_seen": false,
  "current_hash": "bb22…",
  "previous_hash": "aa11…"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/url-change-detection-website-change-monitoring-b1ba4dba/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from scanpay-edge.alextaghiashvili.workers.dev](https://www.zero.xyz/host/scanpay-edge.alextaghiashvili.workers.dev/llms.txt)