API Reference

Base URL

https://api.arbiterapi.com

All endpoints (except /health) are prefixed with /v1 and require an X-API-Key header.

Authentication

curl "https://api.arbiterapi.com/v1/markets" \
  -H "X-API-Key: YOUR_API_KEY"

Endpoints

Markets

Method	Endpoint	Description
GET	`/v1/markets`	List markets with filters
GET	`/v1/markets/search`	Full-text search with advanced filters
GET	`/v1/markets/{id}`	Get a single market

Market Data

Method	Endpoint	Description
GET	`/v1/markets/{id}/price`	Current or historical price
GET	`/v1/markets/{id}/orderbook`	Live orderbook
GET	`/v1/markets/{id}/orderbook/history`	Historical orderbook snapshots
GET	`/v1/markets/{id}/trades`	Trade history
GET	`/v1/markets/{id}/candles`	OHLCV candlestick data

Events

Method	Endpoint	Description
GET	`/v1/events`	List events (grouped markets)
GET	`/v1/events/{slug}`	Get event with child markets

Cross-Platform

Method	Endpoint	Description
GET	`/v1/matching-markets`	Find matching markets across platforms
GET	`/v1/matching-markets/sports/{sport}`	Sports-specific matching by sport + date

Wallets

Method	Endpoint	Description
GET	`/v1/wallets/{address}`	Wallet info + metrics
GET	`/v1/wallets/{address}/trades`	Per-wallet trade history
GET	`/v1/wallets/{address}/positions`	Current holdings per market
GET	`/v1/wallets/{address}/pnl`	Realized PnL over time
GET	`/v1/wallets/{address}/activity`	Merges, splits, redeems

Polymarket Native

Method	Endpoint	Description
GET	`/v1/polymarket/markets`	Raw Gamma API market data
GET	`/v1/polymarket/markets/{condition_id}`	Single market with native fields
GET	`/v1/polymarket/trades`	Trades with tx_hash, maker/taker

Kalshi Native

Method	Endpoint	Description
GET	`/v1/kalshi/markets`	Raw Kalshi API market data
GET	`/v1/kalshi/markets/{ticker}`	Single market with native fields
GET	`/v1/kalshi/trades`	Trades with taker_side, native pricing

WebSocket

Protocol	Endpoint	Description
WS	`/v1/ws`	Real-time trades, prices, orderbook

System

Method	Endpoint	Description
GET	`/health`	Health check + service status (no auth)
GET	`/v1/stats`	Database statistics

Pagination

List endpoints use offset-based pagination:

curl ".../v1/markets?limit=50&offset=100"

Trade and orderbook history endpoints use cursor-based pagination:

# First page
curl ".../v1/markets/{id}/trades?limit=100"
# Response includes: {"cursor": "1774399680782", "has_more": true}

# Next page
curl ".../v1/markets/{id}/trades?limit=100&cursor=1774399680782"

Errors

{
  "detail": "Market not found"
}

Status	Meaning
400	Bad request (invalid params)
401	Missing or invalid API key
404	Resource not found
429	Rate limit exceeded
500	Server error

Getting Started

Core Concepts

SDKs

Polymarket

Kalshi

Markets

Market Data

Events

Cross-Platform

Sports

Wallets

Whales

Webhooks

WebSocket

Auth & Keys

API Reference

Base URL

Authentication

Endpoints

Markets

Market Data

Events

Cross-Platform

Wallets

Polymarket Native

Kalshi Native

WebSocket

System

Errors

​Base URL

​Authentication

​Endpoints

​Markets

​Market Data

​Events

​Cross-Platform

​Wallets

​Polymarket Native

​Kalshi Native

​WebSocket

​System

​Pagination

​Errors

Base URL

Authentication

Endpoints

Markets

Market Data

Events

Cross-Platform

Wallets

Polymarket Native

Kalshi Native

WebSocket

System

Pagination

Errors