# x402.fuchss.app — Watch/Renew x402 Endpoint Monitor

> x402.fuchss.app — Watch/Renew x402 Endpoint Monitor is a paid API for AI agents from x402.fuchss.app, paid per call via x402, $0.2/call, status unknown (last checked 2026-10-13).

Renews or creates a 30-day monitoring subscription for a single x402 endpoint, returning poll/webhook delivery details and a one-time secret for bearer-authenticated management.

## Facts

- Endpoint: POST https://x402.fuchss.app/v1/watch/01KX131YBK3839VYR7XGRKWHXW/renew?utm_source=zero.xyz
- Price: $0.2/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-fuchss-app-watch-renew-x402-endpoint-monitor-9f830e5e
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_WeO-deBh1o8Rnl3gpmEDz

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 x402-fuchss-app-watch-renew-x402-endpoint-monitor-9f830e5e -d '<json body>'
```

Example prompt: Set up 30-day monitoring on https://api.example.com/v1/generate for payto changes and price changes, alert me via Slack at https://hooks.slack.com/services/XXX/YYY/ZZZ, and use a liveness sensitivity of 3.

## When to prefer this

Use this endpoint when you need ongoing, event-driven surveillance of a specific x402-protocol API endpoint — especially when you need to detect critical security events like payTo address changes (potential rug/takeover), price manipulation, or spec regressions that could silently break an AI agent's payment flow. Prefer this over generic uptime monitors because it understands x402 semantics. Use the renew path to extend an existing 30-day watch without losing event history.

## Known failure modes

- Endpoint URL not in observation set — returns 4xx with message that the resource is not publicly listed
- Webhook or Slack URL unreachable — connection-tested before charge; rejected with error and no payment taken
- Invalid delivery URL format — validation error before payment
- More than 5 webhook or Slack URLs supplied — rejected
- Missing required 'endpoint' field — 400 validation error
- x402 payment failure — watch not created

## How this service works

Monitor ONE x402 endpoint for 30 days and get alerted on changes that break agents: payTo changes (critical — possible takeover/rug), price changes, asset/network changes, 402-spec regressions, delisting, and liveness (down/recovered). Account-free: pay, receive a one-time secret + poll URL. Push to multiple signed HTTPS webhooks and/or Slack/Discord incoming webhooks (up to 5 each per watch). Every push URL is connection-tested before payment — unreachable URLs are rejected with no charge. Edit URLs or cancel early for free via bearer-authed PATCH/DELETE /v1/watch/{id}. Poll the append-only event log; nothing is lost between polls.

## Output

Returns a JSON object with: a one-time secret for managing the watch, the watch ID, poll URL for fetching the append-only event log, renew/cancel/edit URLs, expiry timestamp (Unix), subscribed event types, probe interval in seconds, liveness sensitivity setting, and delivery configuration (webhooks/Slack). All required to manage or poll the watch going forward.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "events": {
   "type": "array",
   "items": {
    "type": "string"
   }
  },
  "delivery": {
   "type": "object",
   "required": [
    "webhook_urls",
    "slack_url"
   ],
   "properties": {
    "slack_url": {
     "type": "string"
    },
    "webhook_urls": {
     "type": "array",
     "items": {
      "type": "string"
     }
    }
   }
  },
  "endpoint": {
   "type": "string"
  },
  "liveness_sensitivity_n": {
   "type": "integer"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-fuchss-app-watch-renew-x402-endpoint-monitor-9f830e5e/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402.fuchss.app](https://www.zero.xyz/host/x402.fuchss.app/llms.txt)