Public Finance Amendment Lineage

{
  "data": {
    "chargedAmount": "56001",
    "inputHash": "sha256:86314fe2f16218d93683623027ad22d5f20e32f054f24ecdf4d1bad0b…",
    "limitations": [
      "Public or synthetic inputs only. Caller labels are declarations,…"
    ],
    "productId": "public-amendment-lineage",
    "result": {
      "contractId": "contract-1",
      "dataClass": "synthetic",
      "limitations": [
        "Caller-declared public nonpersonal contract records only. Effect…"
      ],
      "lineage": [
        {
          "changedFields": [],
          "effectiveDate": "2026-01-01",
          "id": "v1",
          "issues": [],
          "parentId": null
        }
      ],
      "serviceId": "public-amendment-lineage"
    },
    "resultHash": "sha256:5fe79669228456a5e2d45b0c250bba25080f21bfd1233621321adc871…",
    "sourceContractAmount": "56000",
    "version": "maha-legacy-adapter/1"
  },
  "proof": {
    "settlement_id": "0x00000000000000000000000000000000000000000000000000000000000000…"
  },
  "success": true
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i -X POST 'https://www.mahastrategies.com/api/v1/verify/public-finance/amendment-lineage' \
  -H 'content-type: application/json' \
  --data-raw '{"contractId":"contract-1","dataClass":"synthetic","publicNonpersonalRecords":true,"revisions":[{"changes":[],"effectiveDate":"2026-01-01","id":"v1","parentId":null},{"changes":[{"after":"B","before":"A","field":"scope"}],"effectiveDate":"2026-02-01","id":"v2","parentId":"v1"}]}'

# 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/verify/public-finance/amendment-lineage' \
  -H 'content-type: application/json' \
  --data-raw '{"contractId":"contract-1","dataClass":"synthetic","publicNonpersonalRecords":true,"revisions":[{"changes":[],"effectiveDate":"2026-01-01","id":"v1","parentId":null},{"changes":[{"after":"B","before":"A","field":"scope"}],"effectiveDate":"2026-02-01","id":"v2","parentId":"v1"}]}' \
  | 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 $0.056001 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.056001" });
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 $0.056001 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fwww.mahastrategies.com%2Fapi%2Fv1%2Fverify%2Fpublic-finance%2Famendment-lineage&method=POST
const res = await pay("https://www.mahastrategies.com/api/v1/verify/public-finance/amendment-lineage", {
  method: "POST",
  headers: { "content-type": "application/json" },
  body: JSON.stringify({
    "contractId": "contract-1",
    "dataClass": "synthetic",
    "publicNonpersonalRecords": true,
    "revisions": [
      {
        "changes": [],
        "effectiveDate": "2026-01-01",
        "id": "v1",
        "parentId": null
      },
      {
        "changes": [
          {
            "after": "B",
            "before": "A",
            "field": "scope"
          }
        ],
        "effectiveDate": "2026-02-01",
        "id": "v2",
        "parentId": "v1"
      }
    ]
  }),
});
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 $0.056001 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.056001"})
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/verify/public-finance/amendment-lineage",
        json={
            "contractId": "contract-1",
            "dataClass": "synthetic",
            "publicNonpersonalRecords": True,
            "revisions": [
                {
                    "changes": [],
                    "effectiveDate": "2026-01-01",
                    "id": "v1",
                    "parentId": None,
                },
                {
                    "changes": [
                        {
                            "after": "B",
                            "before": "A",
                            "field": "scope",
                        },
                    ],
                    "effectiveDate": "2026-02-01",
                    "id": "v2",
                    "parentId": "v1",
                },
            ],
        },
    )
    print(res.status_code, res.text)