Welcome
Build REST and WebSocket integrations for Underdog's regulated prediction markets, from your first request through live trading.
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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.
REST API
Browse the REST operations, schemas, and examples generated from OpenAPI.
WebSocket API
Browse channels, operations, messages, and schemas generated from AsyncAPI.
References
Authentication
Sign requests with API keys or use an interactive bearer token.
Idempotency
Retry mutating requests without executing an operation twice.
Pagination
Page through REST collections using opaque continuation URLs.
Rate Limits
Understand member buckets, response headers, and retry behavior.
Versioning
Pin the dated contract used by REST requests and WebSocket connections.
Glossary
Look up the public terms used consistently throughout UDX.