Prediction Markets

{
  "pagination": {
    "hasMore": true,
    "limit": 2,
    "nextOffset": 2,
    "offset": 0,
    "total": 30834
  },
  "predictionMarkets": [
    {
      "end_ts": "2026-06-23T00:30:00Z",
      "entity_code": "KALSHI",
      "entity_event_category": "Sports",
      "event_name": "Game 3: San Antonio at New York",
      "event_outcome_type": "Multi",
      "event_outcomes": [
        {
          "market_id": "KXNBAGAME-26JUN08SASNYK-NYK_yes.KALSHI",
          "outcome_name": "New York",
          "percentage": 0.54,
          "status": "Open",
          "volume": 7872349.97
        }
      ],
      "event_ticker": "KXNBAGAME-26JUN08SASNYK.KALSHI",
      "is_series": true,
      "pmcs_categories": [
        "SPT",
        "BSKTBL",
        "NBA"
      ]
    }
  ]
}

# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://api.predictionmarketdata.io/prediction-markets?limit=10&search=trump&status=Open'

# 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://api.predictionmarketdata.io/prediction-markets?limit=10&search=trump&status=Open' \
  | 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 $0.001 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.001" });
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 $0.001 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.predictionmarketdata.io%2Fprediction-markets
const res = await pay("https://api.predictionmarketdata.io/prediction-markets?limit=10&search=trump&status=Open");
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 $0.001 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.001"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))

with x402_requests(client) as session:
    res = session.get("https://api.predictionmarketdata.io/prediction-markets?limit=10&search=trump&status=Open")
    print(res.status_code, res.text)