# AUTOGROK Desk — Watch Once (URL Change Detection)

> AUTOGROK Desk — Watch Once (URL Change Detection) is a paid API for AI agents from desk.grokaiapps.com, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-11).

Fetches a URL, computes a SHA-256 hash of its content, and reports whether it has changed since a previous hash was provided.

## Facts

- Endpoint: POST https://desk.grokaiapps.com/v1/jobs/watch-once?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/autogrok-desk-watch-once-url-change-detection-c0802002
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tJKeuTzbyxCK-GLG-7FD7

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 autogrok-desk-watch-once-url-change-detection-c0802002 -d '<json body>'
```

Example prompt: Check if https://example.com/pricing has changed since my last snapshot — my previous hash was ab12cd34ef567890ab12cd34ef567890ab12cd34ef567890ab12cd34ef567890.

## When to prefer this

Use this endpoint when you need a single, lightweight check of whether a URL's content has changed, without storing state server-side. It is ideal for spot-checks, one-shot monitoring, or building your own change-detection loop where you manage the previous hash. Prefer it over full-page extraction endpoints when you only need a change signal, not the content itself.

## Known failure modes

- URL is unreachable or returns non-200 status — fetch fails with an error
- URL is behind authentication or a paywall — content may be incomplete or inaccessible
- Previous hash format is invalid (not a 64-character hex string) — validation error
- URL resolves to dynamic/JS-rendered content — hash may differ each fetch even without meaningful changes
- Rate limit or payment failure — 402 or 429 response

## How this service works

Paid micro-jobs for AI agents and people: URL probe, page extract, watch once, JSON shape, researched brief. Pay per call with x402 (USDC on Base) or with prepaid card packs (Stripe MPP).

## Output

Returns a JSON object with the current SHA-256 hash of the page content, a boolean 'changed' flag (null if no previous_hash was supplied), the UTC timestamp of the fetch, a word count of the page, and the previous hash for reference.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "format": "uri",
   "description": "Public http(s) URL to hash"
  },
  "previous_hash": {
   "type": "string",
   "description": "Prior sha256 hex; omit for baseline (changed=null)"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "url": "https://example.com/",
  "hash": "ab12cd34ef567890ab12cd34ef567890ab12cd34ef567890ab12cd34ef567890",
  "changed": true,
  "fetched_at": "2026-09-21T20:00:00.000Z",
  "word_count": 42,
  "previous_hash": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/autogrok-desk-watch-once-url-change-detection-c0802002/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from desk.grokaiapps.com](https://www.zero.xyz/host/desk.grokaiapps.com/llms.txt)