x402.fuchss.app · watch-endpoint-30d

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.

Call it in 30 seconds

// npm i x402-fetch viem
import { wrapFetchWithPayment } from "x402-fetch";
import { createWalletClient, http } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { base } from "viem/chains";

const account = privateKeyToAccount(process.env.PRIVATE_KEY); // funds USDC on Base
const wallet = createWalletClient({ account, chain: base, transport: http() });
const fetchWithPay = wrapFetchWithPayment(fetch, wallet);

// Pays the $0.2 USDC automatically on the 402, then returns the real response:
const res = await fetchWithPay("https://x402.fuchss.app/v1/watch-endpoint-30d", { method: "POST" });
console.log(await res.json());

# pip install x402 eth-account httpx
import os, asyncio
from eth_account import Account
from x402.clients.httpx import x402HttpxClient

account = Account.from_key(os.environ["PRIVATE_KEY"])  # funds USDC on Base

async def main():
    async with x402HttpxClient(account=account) as client:
        # x402 handles the 402 -> pay ($0.2 USDC) -> retry automatically
        r = await client.get("https://x402.fuchss.app/v1/watch-endpoint-30d")
        print((await r.aread()).decode())

asyncio.run(main())

# 1) An unpaid request returns HTTP 402 with the exact payment terms:
curl -i -X POST "https://x402.fuchss.app/v1/watch-endpoint-30d" \
  -H 'content-type: application/json' \
  -d '{"delivery": {"slack_url": "https://hooks.slack.com/services/\u2026", "webhook_urls": ["https://your-app.example.com/x402-alerts", "https://backup.example.com/x402-alerts"]}, "endpoint": "https://api.example.com/v1/thing", "events": ["payto_change", "price_change", "delisting"], "liveness_sensitivity_n": 2}'

# 2) Paying + retrying requires an x402 client that can sign the USDC
#    authorization (curl alone cannot). See the JS / Python tabs below.

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