> ## Documentation Index
> Fetch the complete documentation index at: https://docs.arbiterapi.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Platforms

> Prediction market platforms aggregated by ARBITER.

## Supported Platforms

### Polymarket

The largest prediction market by volume. Operates on Polygon (Ethereum L2) with on-chain settlement.

* **Market ID prefix**: `poly_`
* **Data sources**: Gamma API (market metadata), CLOB API (orderbooks, price history), WebSocket (real-time trades)
* **Specialties**: Crypto-native, high liquidity, event-based markets

### Kalshi

CFTC-regulated US prediction market. Centralized exchange with USD settlement.

* **Market ID prefix**: `kal_`
* **Data sources**: REST API (markets, trades, candlesticks), WebSocket (requires auth)
* **Specialties**: Regulated, US-focused, native OHLCV candles

### Limitless (Coming Soon)

Decentralized prediction market platform. Integration planned for a future release.

## Platform Filtering

All list endpoints support a `platform` filter:

```bash theme={null}
# Only Polymarket markets
curl ".../v1/markets?platform=polymarket"

# Only Kalshi events
curl ".../v1/events?platform=kalshi"

# Search across all platforms (default)
curl ".../v1/markets/search?q=election"
```