Preflight Deep
by x402 Doctor in Other
Should my agent pay this expensive x402 endpoint? Call it before a costly or repeated payment. Returns the go / caution / no_go verdict plus the full diagnosis, the endpoint's check history per day over 30 days, how reliable the seller's other endpoints are and whether the endpoint moved domains. Never pays the endpoint. Bulk: 1000 credits for $0.80 via /api/v1/credits.
https://x402-doctor.fizzl.eu/api/v1/preflight/deep- Price
- $0.01
- per call in USDC
- Uptime
- 0.0%
- last 30 days
- Response time
- -
- no timed checks yet
- Last check
- Failed
- 3 h ago, next any minute now
Reliability
Latest check failed 3 h ago: Amount "0.01" is not in atomic token units
Status and outage history · Atom feed · Watch with other listings
How to call it
GET https://x402-doctor.fizzl.eu/api/v1/preflight/deep
Each call costs $0.01 in USDC on Base, paid with the request over x402.
Run a free test callOne unpaid request, the way an agent sends it. You see the payment challenge it gets back. Nothing is charged.
Example request
From the listing.
GET https://x402-doctor.fizzl.eu/api/v1/preflight/deep?max_usd=0.5&url=https%3A%2F%2Fichimoku-signal.fizzl.eu%2FsetupsParameters
| Parameter | Type | Required | Description |
|---|---|---|---|
max_usd | string | No | Your budget per call in USD; above it the verdict is no_go. |
method | string | No | HTTP method you will call it with. Default: try GET, then POST. One of: GET, POST. |
network | string | No | CAIP-2 network you want to pay on. |
url | string | Yes | The x402 endpoint you are about to pay (worth it for expensive calls). |
Example response
The provider's example. We can't check it without paying.
Example response, 30 lines
{
"diagnosis": {
"checks": [],
"overall": "pass",
"problems": []
},
"domain": {
"checks": []
},
"history": [
{
"date": "2026-09-28",
"status": "go"
}
],
"options": [],
"reasons": [],
"recommended_option": 0,
"safe_to_pay": true,
"seller": {
"avg_payable_ratio": 1,
"origin": "https://ichimoku-signal.fizzl.eu",
"payable_now": 6,
"resources": 6,
"unreliable": 0
},
"summary": "OK to pay: $0.5 on Base.",
"url": "https://ichimoku-signal.fizzl.eu/setups",
"verdict": "go"
}Call it from code
The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.01.
curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://x402-doctor.fizzl.eu/api/v1/preflight/deep?max_usd=0.5&url=https%3A%2F%2Fichimoku-signal.fizzl.eu%2Fsetups'
# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://x402-doctor.fizzl.eu/api/v1/preflight/deep?max_usd=0.5&url=https%3A%2F%2Fichimoku-signal.fizzl.eu%2Fsetups' \
| grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decodeJavaScript: pay and call
// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";
// Pays at most $0.01 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.01" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);
// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.01 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fx402-doctor.fizzl.eu%2Fapi%2Fv1%2Fpreflight%2Fdeep
const res = await pay("https://x402-doctor.fizzl.eu/api/v1/preflight/deep?max_usd=0.5&url=https%3A%2F%2Fichimoku-signal.fizzl.eu%2Fsetups");
console.log(res.status, await res.text());Python: pay and call
# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client
# Pays at most $0.01 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.01"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))
with x402_requests(client) as session:
res = session.get("https://x402-doctor.fizzl.eu/api/v1/preflight/deep?max_usd=0.5&url=https%3A%2F%2Fichimoku-signal.fizzl.eu%2Fsetups")
print(res.status_code, res.text)Security scan
No findings
We scan names, descriptions and tool definitions for hidden instructions and other prompt-injection patterns.
Recent checks
| When | Result | HTTP | Time | Price |
|---|---|---|---|---|
| 3 h ago | Amount "0.01" is not in atomic token units | 402 | 281 ms | $0.01 |
| 7 h ago | Amount "0.01" is not in atomic token units | 402 | 335 ms | $0.01 |
| 12 h ago | Amount "0.01" is not in atomic token units | 402 | 264 ms | $0.01 |
| 18 h ago | Amount "0.01" is not in atomic token units | 402 | 312 ms | $0.01 |
| 24 h ago | Amount "0.01" is not in atomic token units | 402 | 272 ms | $0.01 |
Show 10 older checks
| 30 h ago | Amount "0.01" is not in atomic token units | 402 | 373 ms | $0.01 |
| 35 h ago | Amount "0.01" is not in atomic token units | 402 | 322 ms | $0.01 |
| 41 h ago | Amount "0.01" is not in atomic token units | 402 | 816 ms | $0.01 |
| 46 h ago | Amount "0.01" is not in atomic token units | 402 | 358 ms | $0.01 |
| 2 days ago | Amount "0.01" is not in atomic token units | 402 | 292 ms | $0.01 |
| 2 days ago | Amount "0.01" is not in atomic token units | 402 | 629 ms | $0.01 |
| 3 days ago | Amount "0.01" is not in atomic token units | 402 | 309 ms | $0.01 |
| 3 days ago | Amount "0.01" is not in atomic token units | 402 | 314 ms | $0.01 |
| 3 days ago | Amount "0.01" is not in atomic token units | 402 | 344 ms | $0.01 |
| 3 days ago | Amount "0.01" is not in atomic token units | 402 | 409 ms | $0.01 |