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

# Introduction

> Real-time prediction market data across Polymarket, Kalshi, Limitless, and OpinionTrade

## What is EventGraph?

EventGraph aggregates prediction market data from four platforms into a single, unified API.
Whether you're building trading tools, research dashboards, or analytics apps — you get
clean, normalized data without integrating multiple platform APIs yourself.

<CardGroup cols={2}>
  <Card title="Events & Markets" icon="chart-line" href="/api-reference/list-events">
    Browse thousands of active prediction markets across all platforms in one call
  </Card>

  <Card title="Search" icon="magnifying-glass" href="/api-reference/search">
    Full-text search across events and markets by title or keyword
  </Card>

  <Card title="Cross-Platform Compare" icon="arrows-left-right" href="/api-reference/compare">
    Find the same event on multiple platforms with match scores and price gaps
  </Card>

  <Card title="Arbitrage Scanner" icon="bolt" href="/api-reference/arbitrage">
    Live arbitrage opportunities with spread %, feasibility scores, and volume data
  </Card>
</CardGroup>

## Data sources

| Platform         | Markets | Refresh rate |
| ---------------- | ------- | ------------ |
| **Polymarket**   | \~3,000 | Every 15 min |
| **Kalshi**       | \~800   | Every 15 min |
| **Limitless**    | \~200   | Every 60 sec |
| **OpinionTrade** | \~150   | Every 15 min |

## Base URL

All API requests use the v1 endpoint with an API key:

```
https://app.eventgraph.ai/api/v1
```

Pass your key in the `X-API-Key` header. See [authentication](/authentication) for details.