# UDX > Build trading and market-data integrations for Underdog's regulated prediction markets. ## Docs - [Welcome](https://docs.underdogexchange.com/): Build integrations for Underdog's prediction markets exchange. - [Quick Start](https://docs.underdogexchange.com/quick-start): Make your first UDX request, from choosing a market to placing an order and reading its outcome. ## Walkthroughs - [Discovering Markets](https://docs.underdogexchange.com/walkthroughs/discovering-markets): Read markets from the market catalog, view their trade history, and read their order books. - [Placing Orders](https://docs.underdogexchange.com/walkthroughs/placing-orders): Place, confirm, amend, and cancel an order over REST or WebSocket, with private streams for its lifecycle and fills. - [Requesting Quotes](https://docs.underdogexchange.com/walkthroughs/requesting-quotes): Create a request for quote, watch the quotes it attracts, and accept one, over REST or WebSocket. - [Creating Quotes](https://docs.underdogexchange.com/walkthroughs/creating-quotes): Find the RFQs soliciting your member, answer one with a quote, follow it through last look, and confirm or cancel it, over REST or WebSocket. ## Concepts - [Participants and Access](https://docs.underdogexchange.com/concepts/participants-and-access): Understand how members, users, scopes, accounts, grants, and API keys determine who can do what, and from which account. - [Markets and Trading](https://docs.underdogexchange.com/concepts/markets-and-trading): Understand binary markets, YES-side pricing, order matching, positions, and the order instructions available through UDX. - [Market Lifecycle](https://docs.underdogexchange.com/concepts/market-lifecycle): Understand market trading statuses, lifecycle filters, and expiration. - [Market Data](https://docs.underdogexchange.com/concepts/market-data): Compare L1, L2, and L3 order book views, then choose between REST snapshots and WebSocket updates for your integration. - [Order Entry](https://docs.underdogexchange.com/concepts/order-entry): Understand what an order is, how time in force, post-only, and self-trade prevention shape it, and how to place, amend, and cancel orders. - [Request for Quote (RFQ)](https://docs.underdogexchange.com/concepts/rfqs): Understand how a request for quote solicits pricing from makers, how a quote is accepted, and how last look decides whether the trade completes. - [Clearing and Settlement](https://docs.underdogexchange.com/concepts/clearing-and-settlement): Understand how trades change account positions and collateral, and how resolved markets settle. ## References - [Connecting](https://docs.underdogexchange.com/reference/connecting): Reach UDX over HTTPS or WebSocket in each environment, and understand what a request or a session is. - [Authentication](https://docs.underdogexchange.com/reference/authentication): Create API credentials, sign REST requests, authenticate WebSocket connections, and see which credential each operation accepts. - [Versioning](https://docs.underdogexchange.com/reference/versioning): Pin dated REST and WebSocket API versions so contract changes are explicit and your integration behaves consistently over time. - [Rate Limits](https://docs.underdogexchange.com/reference/rate-limits): Understand shared member rate limits, read rate-limit state in REST headers and WebSocket responses, and throttle before you are rejected. - [Pagination](https://docs.underdogexchange.com/reference/pagination): Page through REST collections by following each opaque next-page URL while preserving filters and the selected API version. - [Idempotency](https://docs.underdogexchange.com/reference/idempotency): Use idempotency keys to retry mutating REST requests safely, replay completed responses, and avoid executing an operation twice. - [Timestamps](https://docs.underdogexchange.com/reference/timestamps): Read and send UDX timestamps in RFC 3339 form, with UTC responses and microsecond precision. - [Asynchronous Writes](https://docs.underdogexchange.com/reference/asynchronous-writes): Understand why trading writes answer before the exchange decides their outcome, how to read the outcome, and how to retry safely. - [Close Codes](https://docs.underdogexchange.com/reference/close-codes): The WebSocket close codes the exchange sends, what each means, and how to recover. - [Glossary](https://docs.underdogexchange.com/reference/glossary): Find definitions for the market, trading, identity, clearing, and API terms used throughout the UDX REST and WebSocket documentation. ## API Reference ### REST API - [REST API](https://docs.underdogexchange.com/api-reference/rest) #### API Keys - [Create an API Key](https://docs.underdogexchange.com/api-reference/rest/api-keys/create-api-key) - [List API Keys](https://docs.underdogexchange.com/api-reference/rest/api-keys/list-api-keys) - [Revoke an API Key](https://docs.underdogexchange.com/api-reference/rest/api-keys/revoke-api-key) #### Markets - [Get a Market](https://docs.underdogexchange.com/api-reference/rest/markets/get-market) - [Get a Market's Candlesticks](https://docs.underdogexchange.com/api-reference/rest/markets/get-market-candlesticks) - [Get a Market's Order Book](https://docs.underdogexchange.com/api-reference/rest/markets/get-market-orderbook) - [Get a Market's Stats](https://docs.underdogexchange.com/api-reference/rest/markets/get-market-stats) - [Get a Market's Trades](https://docs.underdogexchange.com/api-reference/rest/markets/get-market-trades) - [List Markets](https://docs.underdogexchange.com/api-reference/rest/markets/list-markets) - [List Order Books](https://docs.underdogexchange.com/api-reference/rest/markets/list-orderbooks) - [List Trades](https://docs.underdogexchange.com/api-reference/rest/markets/list-trades) #### Orders - [Amend an Order](https://docs.underdogexchange.com/api-reference/rest/orders/amend-order) - [Cancel an Order](https://docs.underdogexchange.com/api-reference/rest/orders/cancel-order) - [Cancel Orders](https://docs.underdogexchange.com/api-reference/rest/orders/cancel-orders) - [Get an Order](https://docs.underdogexchange.com/api-reference/rest/orders/get-order) - [List Orders](https://docs.underdogexchange.com/api-reference/rest/orders/list-orders) - [Place an Order](https://docs.underdogexchange.com/api-reference/rest/orders/create-order) #### Portfolio - [Create an Account](https://docs.underdogexchange.com/api-reference/rest/portfolio/create-account) - [Get an Account by Client Account ID](https://docs.underdogexchange.com/api-reference/rest/portfolio/get-account-by-client-account-id) - [Get Balance](https://docs.underdogexchange.com/api-reference/rest/portfolio/get-balance) - [Get Positions](https://docs.underdogexchange.com/api-reference/rest/portfolio/get-positions) - [Get Settlements](https://docs.underdogexchange.com/api-reference/rest/portfolio/get-settlements) - [Grant Account Access](https://docs.underdogexchange.com/api-reference/rest/portfolio/create-grant) - [List Accounts](https://docs.underdogexchange.com/api-reference/rest/portfolio/list-accounts) - [List an Account's Grants](https://docs.underdogexchange.com/api-reference/rest/portfolio/list-account-grants) - [List Fills](https://docs.underdogexchange.com/api-reference/rest/portfolio/get-fills) - [Revoke a Grant](https://docs.underdogexchange.com/api-reference/rest/portfolio/revoke-grant) - [Transfer Funds](https://docs.underdogexchange.com/api-reference/rest/portfolio/transfer-between-accounts) #### Quotes - [Accept a Quote](https://docs.underdogexchange.com/api-reference/rest/quotes/accept-quote) - [Cancel a Quote](https://docs.underdogexchange.com/api-reference/rest/quotes/cancel-quote) - [Confirm an Accepted Quote](https://docs.underdogexchange.com/api-reference/rest/quotes/confirm-accepted-quote) - [Create a Quote](https://docs.underdogexchange.com/api-reference/rest/quotes/create-quote) - [Get a Quote](https://docs.underdogexchange.com/api-reference/rest/quotes/get-quote) - [List Account Quotes](https://docs.underdogexchange.com/api-reference/rest/quotes/list-account-quotes) - [List RFQ quotes](https://docs.underdogexchange.com/api-reference/rest/quotes/list-rfq-quotes) #### Rate Limits - [Get the Caller's Rate Limit Profile](https://docs.underdogexchange.com/api-reference/rest/rate-limits/get-rate-limit-profile) #### RFQs - [Create an RFQ](https://docs.underdogexchange.com/api-reference/rest/rfqs/create-rfq) - [Get an RFQ](https://docs.underdogexchange.com/api-reference/rest/rfqs/get-rfq) - [Get RFQ Stats](https://docs.underdogexchange.com/api-reference/rest/rfqs/get-rfq-stats) - [List Account RFQs](https://docs.underdogexchange.com/api-reference/rest/rfqs/list-account-rfqs) - [List RFQ Stats by Series](https://docs.underdogexchange.com/api-reference/rest/rfqs/list-rfq-stats-series) - [List RFQs](https://docs.underdogexchange.com/api-reference/rest/rfqs/list-rfqs) #### Users - [Create an API Key for a User](https://docs.underdogexchange.com/api-reference/rest/users/create-user-api-key) - [Get the Current User](https://docs.underdogexchange.com/api-reference/rest/users/get-current-user) - [List a User's API Keys](https://docs.underdogexchange.com/api-reference/rest/users/list-user-api-keys) - [List Users](https://docs.underdogexchange.com/api-reference/rest/users/list-users) - [Replace a User's Scopes](https://docs.underdogexchange.com/api-reference/rest/users/put-user-scopes) - [Revoke a User's API Key](https://docs.underdogexchange.com/api-reference/rest/users/revoke-user-api-key) ### WebSocket API - [WebSocket API](https://docs.underdogexchange.com/api-reference/websocket) #### Market Data - [Stream Order Books](https://docs.underdogexchange.com/api-reference/websocket/market-data/send-orderbook-data) - [Stream Stats](https://docs.underdogexchange.com/api-reference/websocket/market-data/send-stats-data) - [Stream Trades](https://docs.underdogexchange.com/api-reference/websocket/market-data/send-trade-data) #### Market Lifecycle - [Stream Market Lifecycle Events](https://docs.underdogexchange.com/api-reference/websocket/market-lifecycle/send-market-lifecycle-data) #### Orders - [Amend Orders](https://docs.underdogexchange.com/api-reference/websocket/orders/receive-amend-order-command) - [Cancel Orders](https://docs.underdogexchange.com/api-reference/websocket/orders/receive-cancel-order-command) - [Create Orders](https://docs.underdogexchange.com/api-reference/websocket/orders/receive-create-order-command) - [Stream fills](https://docs.underdogexchange.com/api-reference/websocket/orders/send-fill-data) - [Stream orders](https://docs.underdogexchange.com/api-reference/websocket/orders/send-order-data) #### RFQs - [Accept Quotes](https://docs.underdogexchange.com/api-reference/websocket/rfqs/receive-accept-quote-command) - [Cancel Quotes](https://docs.underdogexchange.com/api-reference/websocket/rfqs/receive-cancel-quote-command) - [Confirm Quotes](https://docs.underdogexchange.com/api-reference/websocket/rfqs/receive-confirm-quote-command) - [Create Quotes](https://docs.underdogexchange.com/api-reference/websocket/rfqs/receive-create-quote-command) - [Create RFQs](https://docs.underdogexchange.com/api-reference/websocket/rfqs/receive-create-rfq-command) - [Stream Quotes](https://docs.underdogexchange.com/api-reference/websocket/rfqs/send-quote-data) - [Stream RFQs](https://docs.underdogexchange.com/api-reference/websocket/rfqs/send-rfq-data) #### Subscriptions - [Request Snapshots](https://docs.underdogexchange.com/api-reference/websocket/subscriptions/receive-snapshot-command) - [Subscribe to Channels](https://docs.underdogexchange.com/api-reference/websocket/subscriptions/receive-subscribe-command) - [Unsubscribe from Channels](https://docs.underdogexchange.com/api-reference/websocket/subscriptions/receive-unsubscribe-command) ## Changelog - [Changelog](https://docs.underdogexchange.com/changelog): Release notes for the public REST and WebSocket APIs. - [WebSocket API — 2026-08-11](https://docs.underdogexchange.com/changelog/websocket-2026-08-11) - [REST API — 2026-07-15](https://docs.underdogexchange.com/changelog/rest-2026-07-15) ## RSS Feeds - [UDX — Changelog](https://docs.underdogexchange.com/changelog/rss.xml) ## Agent resources - [llms-full.txt](https://docs.underdogexchange.com/llms-full.txt): The full Markdown of every page in one file. - [Page Markdown](https://docs.underdogexchange.com/index.md): Append `.md` to any page URL to fetch that page as raw Markdown. - [JSON API](https://docs.underdogexchange.com/api/docs/pages.json): Page index of the JSON docs API; each entry links the page's JSON and Markdown forms. Described by the OpenAPI document at https://docs.underdogexchange.com/openapi.json. - [API catalog](https://docs.underdogexchange.com/.well-known/api-catalog): RFC 9727 linkset of the APIs documented here. - [agent-readability.json](https://docs.underdogexchange.com/agent-readability.json): Manifest of every agent-facing artifact on this site. - [Sitemap](https://docs.underdogexchange.com/sitemap.xml): Every indexable page URL with its last-modified date.