PMXT: what it does, how bots use it, where it stops

What it does

One client class per venue exposes the same calls: fetch_markets, fetch_positions, fetch_balance, create_order. Markets are organized as Event, Market and Outcome, so a bot can address a YES share the same way on every exchange.

The README lists 15 supported exchanges, from Polymarket and Polymarket US through Kalshi, Limitless, Metaculus, Smarkets and Hyperliquid. A COMPLIANCE.md in the repo tracks per-venue feature support.

• pip install pmxt, npm install pmxtjs, npm install -g @pmxt/cli
• npx -y @pmxt/mcp for Claude, Cursor and other MCP clients
• dome-to-pmxt codemod for teams migrating off Dome API
• Zenodo DOI badge in the README, so papers can cite it

Strategy

There is none built in. PMXT gives you the order book, positions and order placement; the edge is your code. The realfishsam arbitrage bot in this directory is the canonical example of a bot written on top of it.

Setup and requirements

Node.js 18 or newer is required even for the Python SDK, because the SDK spawns a local PMXT service. Python 3.8 or newer for pip install pmxt.

Hosted reads need pmxt_api_key and wallet_address. Hosted trading adds private_key, which the SDK wraps into an EIP-712 signer. Self-hosted Kalshi takes api_key plus the RSA private key; self-hosted Polymarket takes private_key and an optional proxy_address with gnosis-safe as the default signature type.

Activity and maintenance

2,138 stars and 265 forks as of 2026-09-08. Created 2026-01-08, last push 2026-07-18. The GitHub API reports 1,264 open issues and pull requests, which is unusual for a repo this age and suggests a large tracker rather than a dead one. The homepage is pmxt.dev and it returned 200 on the check date.

TypeScript is the primary language. The README lists two sponsors and a Discord.

Where it falls short

Hosted writes cover Polymarket, Opinion and Limitless only. Kalshi trading means self-hosting with your own RSA key. The README does not publish hosted pricing or rate limits.

Unified means lowest common denominator on venue-specific features. Check COMPLIANCE.md for the venue you care about before you assume an order type exists.

Who should use it

Anyone writing a cross-venue bot who would rather not maintain three venue clients. Also researchers who need consistent market and price shapes across exchanges.

If you trade one venue only and already have its official SDK working, PMXT adds a dependency without adding much.