pmxt

The ccxt for prediction markets. Hosted unified API for prediction-market data and supported hosted trading — Polymarket, Opinion, and Limitless writes today. Open-source SDKs and a self-host option for venue-native credentials included.
Supported Exchanges
Polymarket
Polymarket US
Kalshi
Limitless
Baozi
Myriad
Opinion
Metaculus
Smarkets
Hyperliquid
Gemini Titan
SuiBets
Rain
Hunch
Why pmxt?
Different prediction market platforms have different APIs, data formats, and conventions. pmxt provides a single, consistent interface to work with all of them.
- Hosted API. Get a key at pmxt.dev/dashboard, construct a client, trade. PMXT handles custody, signing infrastructure, and on-chain settlement.
- Open source (MIT). Self-host the local server for full control — your keys, your machine, no PMXT in the loop. See Self-hosted.
- Language-agnostic. Python and TypeScript SDKs today, with HTTP access for any other language. No lock-in to a single ecosystem.
- Drop-in Dome API replacement. Automatic codemod (
dome-to-pmxt) for teams migrating after the Polymarket acquisition. - Unified trading, not just data. Hosted writes cover Polymarket, Opinion, and Limitless today; self-host for venue-native writes such as Kalshi where supported.
- MCP-native. Use pmxt directly from Claude, Cursor, and other AI agents.
Installation
Ensure that Node.js (>= 18) is installed and the node command is available on your PATH. The Python SDK requires Python >= 3.8.
Python
pip install pmxt
Node.js
npm install pmxtjs
CLI
npm install -g @pmxt/cli
pmxt polymarket markets --query Trump --limit 5
pmxt polymarket fetchMarkets --query Trump --limit 5
pmxt auth status
Running from Source
git clone https://github.com/pmxt-dev/pmxt.git
cd pmxt
npm install
npm run dev
MCP (for AI agents)
npx -y @pmxt/mcp
See @pmxt/mcp for setup with Claude, Cursor, and other MCP-compatible clients.
Migrating from Dome API
If you're currently using Dome API, pmxt is a drop-in replacement for DomeAPI's Polymarket/Kalshi workflows and also exposes PMXT's broader supported venue catalog where current capabilities exist.
Check out pmxt as a Dome API alternative for a detailed migration guide, API comparison, and automatic codemod tool (dome-to-pmxt) to help you transition your code.
# Automatically migrate your codebase
npx dome-to-pmxt ./src
Quickstart
Get your API key at pmxt.dev/dashboard. For reads, only pmxt_api_key and wallet_address are required. For trading, also pass private_key — the SDK auto-wraps it into an EIP-712 signer.
Python
import pmxt
# Reads — pmxt_api_key + wallet_address only
client = pmxt.Polymarket(
pmxt_api_key="pmxt_live_...",
wallet_address="0xYourWalletAddress",
)
positions = client.fetch_positions()
balance = client.fetch_balance()
markets = client.fetch_markets(query="nba")
# Trading — also pass private_key
trader = pmxt.Polymarket(
pmxt_api_key="pmxt_live_...",
wallet_address="0xYourWalletAddress",
private_key="0xYourPrivateKey",
)
order = trader.create_order(
market_id="market-uuid",
outcome_id="outcome-uuid",
side="buy",
order_type="market",
amount=5.0,
denom="usdc",
slippage_pct=30.0,
)
TypeScript
Import style: Use named imports such as
import { Polymarket } from "pmxtjs"for direct classes, orimport pmxt from "pmxtjs"for the namespaced form.
import { Polymarket } from "pmxtjs";
// Reads — pmxtApiKey + walletAddress only
const client = new Polymarket({
pmxtApiKey: "pmxt_live_...",
walletAddress: "0xYourWalletAddress",
});
const positions = await client.fetchPositions();
const balance = await client.fetchBalance();
// Trading — also pass privateKey
const trader = new Polymarket({
pmxtApiKey: "pmxt_live_...",
walletAddress: "0xYourWalletAddress",
privateKey: "0xYourPrivateKey",
});
const order = await trader.createOrder({
marketId: "market-uuid",
outcomeId: "outcome-uuid",
side: "buy",
type: "market",
amount: 5.0,
denom: "usdc",
slippage_pct: 30.0,
});
Prediction market hierarchy
Prediction markets are structured in a hierarchy to group related information.
- Event: The broad topic (e.g., "Who will Trump nominate as Fed Chair?")
- Market: A specific tradeable question (e.g., "Will Trump nominate Kevin Warsh as the next Fed Chair?")
- Outcome: The actual share you buy (e.g., "Yes" or "No")
Trading
pmxt supports unified trading where venues expose writes. Hosted trading is the default for supported hosted venues; self-host when you need raw venue credentials or another venue's write API.
Hosted trading (recommended)
With a PMXT API key, you only need your wallet address and a private key to sign orders. PMXT handles custody, signer infrastructure, and on-chain settlement.
import pmxt
trader = pmxt.Polymarket(
pmxt_api_key="pmxt_live_...",
wallet_address="0xYourWalletAddress",
private_key="0xYourPrivateKey",
)
# 1. Check balance
balance = trader.fetch_balance()
print(f"Available balance: {balance[0].available}")
# 2. Fetch markets
markets = trader.fetch_markets(query='Trump')
# 3. Place an order
order = trader.create_order(
market_id=markets[0].market_id,
outcome_id=markets[0].yes.outcome_id,
side='buy',
order_type='market',
amount=5.0,
denom='usdc',
slippage_pct=30.0,
)
print(f"Order status: {order.status}")
Self-hosted trading (advanced)
Use this when you self-host the local server. See Self-hosted for setup. You provide venue credentials directly — no pmxt_api_key required. For detailed credential setup instructions, see the exchange-specific guides: Polymarket, Kalshi, Limitless.
Polymarket
import os
import pmxt
exchange = pmxt.Polymarket(
private_key=os.getenv('POLYMARKET_PRIVATE_KEY'),
proxy_address=os.getenv('POLYMARKET_PROXY_ADDRESS'), # Optional: For proxy trading
signature_type='gnosis-safe' # Default
)
Kalshi
import os
import pmxt
exchange = pmxt.Kalshi(
api_key=os.getenv('KALSHI_API_KEY'),
private_key=os.getenv('KALSHI_PRIVATE_KEY') # RSA Private Key
)
Limitless
import os
import pmxt
exchange = pmxt.Limitless(
api_key=os.getenv('LIMITLESS_API_KEY'),
private_key=os.getenv('LIMITLESS_PRIVATE_KEY') # For order signing (EIP-712)
)
Self-hosted
To self-host pmxt-core on your own machine: pip install pmxt-core (Python) or npm install pmxt-core (Node.js), then construct any venue client without pmxt_api_key. The SDK spawns a local PMXT service; you supply venue credentials directly. See the self-hosted guide for details.
Documentation
See the API Reference for detailed documentation and more examples.
Examples
Check out the directory for more use cases: