Tax compliance for gasless x402 on SKALE

Why this matters on SKALE specifically

3-step integration

The handler

SKALE's x402 cookbook uses @x402/hono with the DirtRoad facilitator. Add the AgentTax fetch inside your route handler — that's it.

// SKALE x402 merchant — record each gasless settlement to AgentTax.
// SKALE is gasless: $0.0001 transactions are profitable, which means
// compliance becomes necessary at transaction counts Avalara can't handle.
import { Hono } from "hono";
import { paymentMiddleware, x402ResourceServer } from "@x402/hono";
import { ExactEvmScheme } from "@x402/evm/exact/server";
import { HTTPFacilitatorClient } from "@x402/core/server";

const app = new Hono();
const facilitator = { url: "https://facilitator.dirtroad.dev" };
const facilitatorClient = new HTTPFacilitatorClient(facilitator);

// Flip SKALE_CHAIN_ID between 324705682 (Sepolia testnet)
// and 1187947933 (SKALE Base Mainnet) without code changes.
const NETWORK = `eip155:${process.env.SKALE_CHAIN_ID || "324705682"}`;

app.use("*", paymentMiddleware(
  {
    "GET /paid": {
      accepts: [{
        scheme: "exact",
        network: NETWORK,
        payTo: process.env.RECEIVING_ADDRESS,
        price: {
          amount: "10000",                 // 0.01 USDC, atomic units (6 decimals)
          asset: process.env.PAYMENT_TOKEN_ADDRESS,
        },
      }],
    },
  },
  new x402ResourceServer(facilitatorClient).register(NETWORK, new ExactEvmScheme()),
));

async function recordTax({ amount, buyerState, counterpartyId }) {
  const res = await fetch("https://agenttax.io/api/v1/calculate", {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "Authorization": `Bearer ${process.env.AGENTTAX_API_KEY}`,
    },
    body: JSON.stringify({
      role: "seller",
      amount,
      buyer_state: buyerState,
      transaction_type: "compute",
      counterparty_id: counterpartyId,
    }),
  });
  if (!res.ok) throw new Error(`AgentTax ${res.status}`);
  return res.json();
}

app.get("/paid", async (c) => {
  const buyerState = c.req.query("buyer_state") || process.env.AGENTTAX_DEFAULT_STATE;
  try {
    const tax = await recordTax({
      amount: 0.01,
      buyerState,
      counterpartyId: c.req.header("x-payer-address") || "anonymous",
    });
    return c.json({
      data: "your paid resource",
      agenttax: {
        transaction_id: tax.transaction_id,
        tax_amount: tax.sales_tax?.amount,
        tax_rate: tax.sales_tax?.combined_rate,
        jurisdiction: tax.sales_tax?.jurisdiction,
      },
    });
  } catch {
    return c.json({ data: "your paid resource", agenttax: { error: "record_failed" } });
  }
});

Sub-cent settlement is where x402 and state sales tax disagree most, and rounding is not the only place. The x402 tax compliance reference works through the four gaps that surface in production.

Response shape

{
  "success": true,
  "role": "seller",
  "amount": 100,
  "buyer_state": "TX",
  "transaction_type": "compute",
  "jurisdiction": "Texas",
  "combined_rate": 0.0625,
  "classification_basis": "data_processing",
  "total_tax": 5,
  "sales_tax": {
    "jurisdiction": "Texas",
    "combined_rate": 0.0625,
    "amount": 5,
    "taxable_amount": 80,
    "taxable_percentage": 0.8,
    "note": "TX Tax Code §151.351 — 20% statutory exemption"
  },
  "use_tax": null,
  "confidence": {
    "score": 72,
    "level": "partial"
  },
  "transaction_id": "txn_skale_abc123"
}

SKALE Base chains

New to x402 in general? See the generic x402 integration guide.