FLINT

Verify an AI agent's authority and integrity before a transaction; returns a four-state verdict and a signed verification record

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 $0.001 USDC automatically on the 402, then returns the real response:
const res = await fetchWithPay("https://flint.network/api/x402/verify", { 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 ($0.001 USDC) -> retry automatically
        r = await client.get("https://flint.network/api/x402/verify")
        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://flint.network/api/x402/verify" \
  -H 'content-type: application/json' \
  -d '{"agent_claim": {"agent_id": "invoice-bot", "agent_runtime_hint": "api_meter", "principal_hint": "coinbase", "wallet_type": "eoa"}, "declared_scope": {"allowed_counterparties": ["acme_checkout"], "max_amount_per_tx_display": "50.00"}, "merchant_reference": "acme_checkout", "nonce": "x402-demo-01J7QJ3VQV4X30B6XEXBHHDM", "partner_id": "bazaar_demo", "timestamp": "2026-06-13T12:00:00.000Z", "transaction": {"amount_display": "24.50", "chain": "eip155:84532", "counterparty_address": "0x742d35Cc6634C0532925a3b844Bc454e4438f44e", "token": {"issuer": "circle", "symbol": "USDC"}}}'

# 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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