Pgn Headers

{
  "asOf": "2026-10-12T01:02:03.845Z",
  "degraded": false,
  "disclaimer": "Screening signal computed from the named public source. Not financial, legal or investment advice; provided as is. Verify at the source before acting.",
  "firstMoves": [
    "e4",
    "e5",
    "…4 more"
  ],
  "fullMoves": 3,
  "halfMoves": 6,
  "missingRosterTags": [],
  "notChecked": [
    "whether the moves are legal",
    "NAGs, variations and comment content",
    "…1 more"
  ],
  "reasons": [],
  "resultInMovetext": "1-0",
  "sevenTagRosterComplete": true,
  "source": "computed locally (PGN standard section 8)",
  "summary": "7 tag(s), 6 half-move(s) (3 full moves).",
  "tagCount": 7,
  "tags": {
    "Black": "Duke Karl / Count Isouard",
    "Date": "1858.??.??",
    "Event": "Casual game",
    "Result": "1-0",
    "Round": "?",
    "Site": "Paris FRA",
    "White": "Paul Morphy"
  },
  "verdict": "VALID_TAGS"
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://chess-notation.x402tookit.com/pgn-headers?pgn=%5BEvent+%22Casual+game%22%5D%0A%5BSite+%22Paris+FRA%22%5D%0A%5BDate+%221858.%3F%3F.%3F%3F%22%5D%0A%5BRound+%22%3F%22%5D%0A%5BWhite+%22Paul+Morphy%22%5D%0A%5BBlack+%22Duke+Karl+%2F+Count+Isouard%22%5D%0A%5BResult+%221-0%22%5D%0A%0A1.+e4+e5+2.+Nf3+d6+3.+d4+Bg4+1-0'

# 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 - 'https://chess-notation.x402tookit.com/pgn-headers?pgn=%5BEvent+%22Casual+game%22%5D%0A%5BSite+%22Paris+FRA%22%5D%0A%5BDate+%221858.%3F%3F.%3F%3F%22%5D%0A%5BRound+%22%3F%22%5D%0A%5BWhite+%22Paul+Morphy%22%5D%0A%5BBlack+%22Duke+Karl+%2F+Count+Isouard%22%5D%0A%5BResult+%221-0%22%5D%0A%0A1.+e4+e5+2.+Nf3+d6+3.+d4+Bg4+1-0' \
  | 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 $0.02 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.02" });
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 $0.02 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fchess-notation.x402tookit.com%2Fpgn-headers
const res = await pay("https://chess-notation.x402tookit.com/pgn-headers?pgn=%5BEvent+%22Casual+game%22%5D%0A%5BSite+%22Paris+FRA%22%5D%0A%5BDate+%221858.%3F%3F.%3F%3F%22%5D%0A%5BRound+%22%3F%22%5D%0A%5BWhite+%22Paul+Morphy%22%5D%0A%5BBlack+%22Duke+Karl+%2F+Count+Isouard%22%5D%0A%5BResult+%221-0%22%5D%0A%0A1.+e4+e5+2.+Nf3+d6+3.+d4+Bg4+1-0");
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 $0.02 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.02"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://chess-notation.x402tookit.com/pgn-headers?pgn=%5BEvent+%22Casual+game%22%5D%0A%5BSite+%22Paris+FRA%22%5D%0A%5BDate+%221858.%3F%3F.%3F%3F%22%5D%0A%5BRound+%22%3F%22%5D%0A%5BWhite+%22Paul+Morphy%22%5D%0A%5BBlack+%22Duke+Karl+%2F+Count+Isouard%22%5D%0A%5BResult+%221-0%22%5D%0A%0A1.+e4+e5+2.+Nf3+d6+3.+d4+Bg4+1-0")
    print(res.status_code, res.text)