@arbiterapi/sdk

TypeScript SDK for the Arbiter prediction market API. Unified access to Polymarket and Kalshi with normalized data, historical trades, OHLCV candles, and real-time WebSocket streaming.

Install

npm install @arbiterapi/sdk

Quick Start

import { ArbiterClient } from "@arbiterapi/sdk";

const client = new ArbiterClient({ apiKey: "YOUR_API_KEY" });

// List markets
const markets = await client.markets.list({ limit: 10 });

// Get a specific market
const market = await client.markets.get("poly_0x3a75...");

// Search markets
const results = await client.markets.search({ q: "bitcoin" });

// Get orderbook
const book = await client.markets.orderbook("poly_0x3a75...");

// Get trades
const trades = await client.markets.trades("poly_0x3a75...");

// Get OHLCV candles
const candles = await client.markets.candles("poly_0x3a75...", {
  interval: "1h",
  start: new Date("2026-01-01"),
  end: new Date(),
});

// Get current or historical price
const price = await client.markets.price("poly_0x3a75...");
const historicalPrice = await client.markets.price("poly_0x3a75...", {
  at_time: 1774650000,
});

// Events (grouped markets)
const events = await client.events.list({ limit: 10 });
const event = await client.events.get("us-presidential-election-2028");

// Cross-platform matching
const matches = await client.matching.list({ confidence: "high" });

// Wallet analytics (Polymarket)
const wallet = await client.wallets.get("0x1234...");
const pnl = await client.wallets.pnl("0x1234...");
const positions = await client.wallets.positions("0x1234...");

// Health check (no auth)
const health = await client.health();

API Reference

Full documentation at docs.arbiterapi.com.

Get an API Key

Sign up at arbiterapi.com/signup.