ToolVet
80trust / 100

Evm Balance

by twin.unykorn.org in Onchain & crypto

x402 APIPassing, checked 4 h ago

Multi-chain EVM balance read — native + ERC20, up to 5 chains in ONE call — Genesis402 / UnyKorn Operator Network

POST
https://twin.unykorn.org/evm-balance
Price
$0.008
per call in USDC
Uptime
100%
last 30 days
Response time
138 ms
420 ms slowest 5%
Last check
Passed
4 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 · Watch with other listings

How to call it

POST https://twin.unykorn.org/evm-balance

Each call costs $0.008 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.

POST https://twin.unykorn.org/evm-balance
content-type: application/json

{
  "params": {
    "address": "0x7d9a65d06dcc435a52D5880C6310Bd6E96c156DB",
    "chains": [
      "base",
      "polygon"
    ],
    "tokens": [
      "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
    ]
  }
}

Parameters

ParameterTypeRequiredDescription
paramsobjectYes

Example response

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

Example response, 35 lines
{
  "address": "0x7d9a…156DB",
  "balances": {
    "base": {
      "available": true,
      "chain_id": 8453,
      "native": "0.000009745904142039",
      "native_symbol": "ETH",
      "tokens": {
        "0x8335…2913": {
          "available": true,
          "balance": "8",
          "decimals": 6,
          "raw": "8000000",
          "symbol": "USDC"
        }
      }
    }
  },
  "evidence_hash": "sha256:<64hex>",
  "ok": true,
  "receipt": {
    "amount_usd": 0.008,
    "receipt_id": "g402-<16hex>",
    "tx_hash": "0x<64hex>"
  },
  "sources": [
    {
      "name": "base:eth_getBalance",
      "ok": true,
      "url": "https://mainnet.base.org"
    }
  ],
  "type": "evm-balance"
}

Call it from code

The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.008.

curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://twin.unykorn.org/evm-balance' \
  -H 'content-type: application/json' \
  --data-raw '{"params":{"address":"0x7d9a65d06dcc435a52D5880C6310Bd6E96c156DB","chains":["base","polygon"],"tokens":["0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"]}}'

# 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 - -X POST 'https://twin.unykorn.org/evm-balance' \
  -H 'content-type: application/json' \
  --data-raw '{"params":{"address":"0x7d9a65d06dcc435a52D5880C6310Bd6E96c156DB","chains":["base","polygon"],"tokens":["0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"]}}' \
  | 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 $0.008 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.008" });
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 $0.008 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Ftwin.unykorn.org%2Fevm-balance&method=POST
const res = await pay("https://twin.unykorn.org/evm-balance", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "params": {
      "address": "0x7d9a65d06dcc435a52D5880C6310Bd6E96c156DB",
      "chains": [
        "base",
        "polygon"
      ],
      "tokens": [
        "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
      ]
    }
  }),
});
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 $0.008 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.008"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://twin.unykorn.org/evm-balance",
        json={
            "params": {
                "address": "0x7d9a65d06dcc435a52D5880C6310Bd6E96c156DB",
                "chains": [
                    "base",
                    "polygon",
                ],
                "tokens": [
                    "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
                ],
            },
        },
    )
    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
4 h agoPassed402227 ms$0.008
8 h agoPassed402192 ms$0.008
13 h agoPassed402134 ms$0.008
17 h agoPassed402153 ms$0.008
21 h agoPassed402174 ms$0.008
Show 10 older checks
25 h agoPassed402199 ms$0.008
30 h agoPassed402187 ms$0.008
34 h agoPassed402128 ms$0.008
38 h agoPassed402123 ms$0.008
43 h agoPassed402131 ms$0.008
47 h agoPassed402135 ms$0.008
2 days agoPassed402202 ms$0.008
2 days agoPassed402171 ms$0.008
2 days agoPassed402133 ms$0.008
3 days agoPassed402420 ms$0.008