# AgentProof Watch URL

> AgentProof Watch URL is a paid API for AI agents from agentproof.hatchable.site, paid per call via x402, $0.25/call, status unknown (last checked 2026-10-11).

Registers a URL for continuous monitoring and returns a provenance receipt with an integrity hash whenever the page content changes

## Facts

- Endpoint: POST https://agentproof.hatchable.site/api/paid/watch_url?utm_source=zero.xyz
- Price: $0.25/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agentproof-watch-url-a939bf6e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_tjazTqh2-MVoVLRwuqbuB

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 agentproof-watch-url-a939bf6e -d '<json body>'
```

Example prompt: Set up a watch on https://example.com/data/prices.json so I get a provenance receipt with an integrity hash every time that page changes — I need to prove to auditors that my agent is reading the canonical source.

## When to prefer this

Choose this endpoint when an autonomous agent needs cryptographically verifiable proof that it read a specific URL at a specific time, particularly for regulatory, audit, or trust-infrastructure use cases. It is distinct from generic uptime monitors or scraping tools because it produces a machine-payable provenance receipt (Agent Transaction Passport™) with an integrity hash, suitable for use as evidence in autonomous transaction logs.

## Known failure modes

- URL is unreachable or returns a non-200 status — watch registration may fail or receipt integrity hash cannot be generated
- Invalid or malformed URL in the request body — likely returns a 400 bad request
- Payment of 0.25 USDC not received or x402 payment header missing — returns 402 Payment Required
- URL behind authentication or firewall that blocks the monitoring agent — watch may register but content cannot be fetched
- Service unavailability on hatchable.site — returns 5xx error

## How this service works

AgentProof publishes Agent Transaction Passport™ and provides machine-paid evidence, provenance receipts, source comparison and change monitoring for autonomous transactions.

## Output

Returns a JSON object confirming the watch was registered (ok: true), a tool identifier ('watch_url'), a receipt object containing a UUID receipt ID and a SHA-256 integrity hash of the monitored URL's current content, and a service identifier ('AgentProof'). This receipt serves as a tamper-evident provenance record for autonomous transaction audit trails.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "format": "uri"
  },
  "webhook_url": {
   "type": "string",
   "format": "uri"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "tool": "watch_url",
  "receipt": {
   "id": "uuid",
   "integrity_sha256": "..."
  },
  "service": "AgentProof"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agentproof-watch-url-a939bf6e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agentproof.hatchable.site](https://www.zero.xyz/host/agentproof.hatchable.site/llms.txt)