Demand Live X402 Payment Preflight

{
  "inputHash": "sha256:f7939781fcb75d5934b6b1e57fab7973742c70482e254ab338644bf42…",
  "limitations": [
    "Public or synthetic input only. Caller labels do not detect sens…"
  ],
  "productId": "live-x402-payment-preflight",
  "receiptDigest": "sha256:a4738c7dee75db2c9a17de1e65b969c624ec21adde68f445b1d97b3d5…",
  "result": {
    "allRequiredQuotesValid": true,
    "deliveryTested": false,
    "observation": {
      "challengeDigest": "sha256:2e3c2e86639945575fa369af54f340405c259551bf3f2fc8e80280f08…",
      "challengeState": "observed",
      "durationMs": 20,
      "networks": [
        {
          "amountBaseUnits": "1000",
          "network": "eip155:8453",
          "reasons": [],
          "state": "valid_quote"
        }
      ],
      "observedAt": "2026-10-12T12:00:00.000Z",
      "resource": "https://www.mahastrategies.com/api/v1/compress",
      "responseStatus": 402,
      "schemaDigest": "sha256:996dfe72b52d6610106b64cf47bc4d22123c1dc8370a91608cc3b699f…",
      "schemaState": "present_not_validated"
    },
    "paymentsMade": 0
  },
  "resultHash": "sha256:902d833fa3a16cd2b546ea2e30e34d0700d67905ad6d778d226a51fe9…",
  "version": "maha-demand6/1.0.0"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://www.mahastrategies.com/api/v1/demand/live-x402-payment-preflight' \
  -H 'content-type: application/json' \
  --data-raw '{"dataClass":"synthetic","expectedPayee":"0xec84c1cd6602bbe387bc8e6f0d3c062f2762de28","maximumAmountBaseUnits":"2000","requiredNetworks":["eip155:8453","eip155:42161"],"resource":"https://www.mahastrategies.com/api/v1/compress"}'

# 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://www.mahastrategies.com/api/v1/demand/live-x402-payment-preflight' \
  -H 'content-type: application/json' \
  --data-raw '{"dataClass":"synthetic","expectedPayee":"0xec84c1cd6602bbe387bc8e6f0d3c062f2762de28","maximumAmountBaseUnits":"2000","requiredNetworks":["eip155:8453","eip155:42161"],"resource":"https://www.mahastrategies.com/api/v1/compress"}' \
  | 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 $0.0349 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.0349" });
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 $0.0349 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fwww.mahastrategies.com%2Fapi%2Fv1%2Fdemand%2Flive-x402-payment-preflight&method=POST
const res = await pay("https://www.mahastrategies.com/api/v1/demand/live-x402-payment-preflight", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "dataClass": "synthetic",
    "expectedPayee": "0xec84c1cd6602bbe387bc8e6f0d3c062f2762de28",
    "maximumAmountBaseUnits": "2000",
    "requiredNetworks": [
      "eip155:8453",
      "eip155:42161"
    ],
    "resource": "https://www.mahastrategies.com/api/v1/compress"
  }),
});
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 $0.0349 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.0349"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.post(
        "https://www.mahastrategies.com/api/v1/demand/live-x402-payment-preflight",
        json={
            "dataClass": "synthetic",
            "expectedPayee": "0xec84c1cd6602bbe387bc8e6f0d3c062f2762de28",
            "maximumAmountBaseUnits": "2000",
            "requiredNetworks": [
                "eip155:8453",
                "eip155:42161",
            ],
            "resource": "https://www.mahastrategies.com/api/v1/compress",
        },
    )
    print(res.status_code, res.text)