---
title: Welcome
description: Build REST and WebSocket integrations for Underdog's regulated prediction markets, from your first request through live trading.
sidebar:
  label: Welcome
  order: 1
---

## Get started

<CardGroup cols={1}>
  <Card title="Making your first request" icon="rocket" href="/quick-start">
    Call the public markets API in UAT, then add authentication for private operations.
  </Card>
</CardGroup>

## APIs

UDX exposes request/response workflows through REST and live market data through WebSockets.
The public interfaces use UDX concepts directly, so integrations do not need to know the exchange or clearing technology behind them.

The published OpenAPI and AsyncAPI specifications define the public interfaces. A REST operation is public only after it appears in the generated API reference. An HTTP `501 Not Implemented` response means the operation is not available in the environment you called.

<CardGroup cols={2}>
  <Card title="REST API" icon="code-xml" href="/api-reference">
    Browse the REST operations, schemas, and examples generated from OpenAPI.
  </Card>
  <Card title="WebSocket API" icon="radio-tower" href="/websocket-api">
    Browse channels, operations, messages, and schemas generated from AsyncAPI.
  </Card>
</CardGroup>

## References

<CardGroup cols={3}>
  <Card title="Authentication" icon="key-round" href="/authentication">
    Sign requests with API keys or use an interactive bearer token.
  </Card>
  <Card title="Idempotency" icon="refresh-cw" href="/idempotency">
    Retry mutating requests without executing an operation twice.
  </Card>
  <Card title="Pagination" icon="list-filter" href="/pagination">
    Page through REST collections using opaque continuation URLs.
  </Card>
  <Card title="Rate Limits" icon="gauge" href="/rate-limits">
    Understand member buckets, response headers, and retry behavior.
  </Card>
  <Card title="Versioning" icon="git-branch" href="/versioning">
    Pin the dated contract used by REST requests and WebSocket connections.
  </Card>
  <Card title="Glossary" icon="list-tree" href="/glossary">
    Look up the public terms used consistently throughout UDX.
  </Card>
</CardGroup>

## Specifications

<CardGroup cols={2}>
  <Card title="OpenAPI specification" icon="file-code-2" href="/openapi.yml">
    Download the machine-readable REST contract for local tooling and code generation.
  </Card>
  <Card title="AsyncAPI specification" icon="file-code-2" href="/asyncapi.yml">
    Download the machine-readable WebSocket contract for local tooling and code generation.
  </Card>
</CardGroup>