ToolVet
78trust / 100

Postcode

by SiteCheck in Weather & location

x402 APIPassing, checked 3 h ago

Place names and coordinates for a postcode. GB adds district, ward and constituency (postcodes.io); other countries use Zippopotam.us for ZIP and postal codes. A postcode that does not exist answers 404, not charged.

GET
https://api.sitecheck-api.workers.dev/api/postcode
Price
$0.001
per call in USDC
Uptime
100%
last 30 days
Response time
44 ms
44 ms slowest 5%
Last check
Passed
3 h ago, next any minute now

Run a free test callHow to call it

Reliability

All checks passedSome failedAll failedNot checked

Status and outage history · Atom feed

How to call it

GET https://api.sitecheck-api.workers.dev/api/postcode

Each call costs $0.001 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://api.sitecheck-api.workers.dev/api/postcode?code=SW1A+1AA&country=GB

Parameters

ParameterTypeRequiredDescription
codestringYesPostcode or ZIP code
countrystringYesISO 3166 alpha-2 code, e.g. GB

Example response

The provider's example. We can't check it without paying.

{
  "attribution": "Contains OS data © Crown copyright and database right; postcodes.io (Open Government Licence v3.0)",
  "checkedAt": "2026-10-14T04:49:24.511Z",
  "code": "SW1A 1AA",
  "country": "GB",
  "places": [
    {
      "constituency": "Cities of London and Westminster",
      "county": null,
      "district": "Westminster",
      "lat": 51.50101,
      "lon": -0.141563,
      "placeName": "St James's",
      "region": "London"
    }
  ],
  "source": "postcodes.io (https://api.postcodes.io)"
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.001.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://api.sitecheck-api.workers.dev/api/postcode?code=SW1A+1AA&country=GB'

# 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://api.sitecheck-api.workers.dev/api/postcode?code=SW1A+1AA&country=GB' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode
JavaScript: 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 $0.001 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.001" });
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 $0.001 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.sitecheck-api.workers.dev%2Fapi%2Fpostcode
const res = await pay("https://api.sitecheck-api.workers.dev/api/postcode?code=SW1A+1AA&country=GB");
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 $0.001 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.001"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://api.sitecheck-api.workers.dev/api/postcode?code=SW1A+1AA&country=GB")
    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

WhenResultHTTPTimePrice
3 h agoPassed40244 ms$0.001
7 h agoPassed40243 ms$0.001
11 h agoPassed40288 ms$0.001