X402 Failure Fact Classifier

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://api.blockchainmoneymap.com/api/x402/x402-failure-fact-classifier' \
  -H 'content-type: application/json' \
  --data-raw '{"caller_context":{"client_name":"example-agent","client_version":"1.0.0","environment":"test","integration_step":"challenge"},"expected_facts":{"amount":"0.01","currency":"USDC","network":"base","receiver":"0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a","resource_path":"/api/x402/wallet-snapshot","scheme":"exact","tool_id":"wallet_snapshot"},"failure_facts":{"amount":"0.01","currency":"USDC","http_status":402,"network":"base","present_header_names":["payment-required","content-type"],"receiver":"0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a","resource_path":"/api/x402/wallet-snapshot","scheme":"exact","x402_version":2}}'

# 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://api.blockchainmoneymap.com/api/x402/x402-failure-fact-classifier' \
  -H 'content-type: application/json' \
  --data-raw '{"caller_context":{"client_name":"example-agent","client_version":"1.0.0","environment":"test","integration_step":"challenge"},"expected_facts":{"amount":"0.01","currency":"USDC","network":"base","receiver":"0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a","resource_path":"/api/x402/wallet-snapshot","scheme":"exact","tool_id":"wallet_snapshot"},"failure_facts":{"amount":"0.01","currency":"USDC","http_status":402,"network":"base","present_header_names":["payment-required","content-type"],"receiver":"0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a","resource_path":"/api/x402/wallet-snapshot","scheme":"exact","x402_version":2}}' \
  | grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decode

// 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%2Fapi.blockchainmoneymap.com%2Fapi%2Fx402%2Fx402-failure-fact-classifier&method=POST
const res = await pay("https://api.blockchainmoneymap.com/api/x402/x402-failure-fact-classifier", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "caller_context": {
      "client_name": "example-agent",
      "client_version": "1.0.0",
      "environment": "test",
      "integration_step": "challenge"
    },
    "expected_facts": {
      "amount": "0.01",
      "currency": "USDC",
      "network": "base",
      "receiver": "0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a",
      "resource_path": "/api/x402/wallet-snapshot",
      "scheme": "exact",
      "tool_id": "wallet_snapshot"
    },
    "failure_facts": {
      "amount": "0.01",
      "currency": "USDC",
      "http_status": 402,
      "network": "base",
      "present_header_names": [
        "payment-required",
        "content-type"
      ],
      "receiver": "0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a",
      "resource_path": "/api/x402/wallet-snapshot",
      "scheme": "exact",
      "x402_version": 2
    }
  }),
});
console.log(res.status, await res.text());

# 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.post(
        "https://api.blockchainmoneymap.com/api/x402/x402-failure-fact-classifier",
        json={
            "caller_context": {
                "client_name": "example-agent",
                "client_version": "1.0.0",
                "environment": "test",
                "integration_step": "challenge",
            },
            "expected_facts": {
                "amount": "0.01",
                "currency": "USDC",
                "network": "base",
                "receiver": "0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a",
                "resource_path": "/api/x402/wallet-snapshot",
                "scheme": "exact",
                "tool_id": "wallet_snapshot",
            },
            "failure_facts": {
                "amount": "0.01",
                "currency": "USDC",
                "http_status": 402,
                "network": "base",
                "present_header_names": [
                    "payment-required",
                    "content-type",
                ],
                "receiver": "0x2211E12e6Bc8Da27B48B9DD66A55f5C3388D713a",
                "resource_path": "/api/x402/wallet-snapshot",
                "scheme": "exact",
                "x402_version": 2,
            },
        },
    )
    print(res.status_code, res.text)