> ## Documentation Index > Fetch the complete documentation index at: https://docs.limitless.exchange/llms.txt > Use this file to discover all available pages before exploring further. # Get Pack > Returns catalogue details. A returned Pack is not necessarily active or currently eligible; obtain a partner quote before buying. Hidden Packs return 404. Returns catalogue details for a Pack UUID. No authentication is required. Hidden and nonexistent Packs return `404`. A returned Pack may be closed or ineligible. Check its state and request a [partner quote](/api-reference/packs/quote-pack.md) for the desired stake before preparing a purchase. The response is publicly cacheable for 30 seconds with 60 seconds of stale-while-revalidate. The catalogue ID identifies the product. Buying creates a separate position ID, which is used for [tracking](/api-reference/packs/get-position.md) and [claiming](/api-reference/packs/claim-position.md). ## OpenAPI ````yaml GET /parlay/packs/{id} openapi: 3.0.0 info: title: Limitless Exchange API description: >- # Limitless Exchange Trading API *Production-ready API for prediction market trading, portfolio management, and market data* > 🎯 **Quick Navigation**: [Authentication](#tag/authentication) | [Markets](#tag/markets) | [Trading](#tag/trading) | [Portfolio](#tag/portfolio) --- ## 🚀 Quick Start Choose your preferred programming language for complete end-to-end implementation: ### Overview The Limitless Exchange API offers both REST and WebSocket integration: **REST API (Trading)**: 1. **🔐 Authentication**: Use API key for all programmatic access 2. **📊 Fetch Market Data**: Get market info including venue contract addresses (once per market) 3. **📋 Order Creation**: Build and sign orders using EIP-712 structured data 4. **🚀 Order Submission**: Submit signed orders and receive confirmations **WebSocket API (Real-Time Data)**: 1. **🔌 Connection**: Connect to `/markets` namespace for real-time updates 2. **📊 Subscriptions**: Subscribe to market prices and position changes 3. **📡 Events**: Handle live market data and transaction updates ### 🔐 Authentication for API Users > **⚠️ DEPRECATION NOTICE**: Cookie-based session authentication is deprecated and will be removed within weeks. Please migrate to API keys immediately. | Method | Header | Status | |--------|--------|--------| | **API Key** | `X-API-Key: lmts_...` | ✅ Required for programmatic access | | Cookie Session | `Cookie: limitless_session=...` | ⚠️ Deprecated (removal imminent) | **Getting an API Key** API keys can only be created via the Limitless Exchange UI: 1. Log in to [limitless.exchange](https://limitless.exchange) using your wallet 2. Click your profile menu (top right) 3. Select "Api keys" 4. Generate a new key **Using Your API Key** Include in all requests via the `X-API-Key` header: ```bash # REST API curl -H "X-API-Key: lmts_your_key_here" https://api.limitless.exchange/markets # WebSocket - pass X-API-Key header during connection handshake ``` ### Migration from Cookie to API Key If you're currently using cookie-based authentication, migrate by: 1. **Generate an API key** via the UI (profile menu → Api keys) 2. **Replace cookie header** with API key header: ```diff # Before (deprecated) - Cookie: limitless_session=your_session_token # After + X-API-Key: lmts_your_key_here ``` 3. **Remove session management code** - no more login flow or cookie handling needed ### Important: Venue System for CLOB Markets CLOB markets use a **venue system** where each market is associated with specific contract addresses. Before placing orders: 1. **Fetch market data once**: `GET /markets/:slug` returns venue information 2. **Use venue.exchange**: This is the `verifyingContract` for EIP-712 order signing 3. **Cache the venue**: Venue data is static per market - fetch once and reuse **Sample venue response:** ```json { "venue": { "exchange": "0xA1b2C3...", "adapter": "0xD4e5F6..." } } ``` ### Required Approvals Before trading, set up token approvals based on order type: | Order Type | Market Type | Approve To | |------------|-------------|------------| | BUY | All CLOB | USDC → `venue.exchange` | | SELL | Simple CLOB | CT → `venue.exchange` | | SELL | NegRisk/Grouped | CT → `venue.exchange` AND `venue.adapter` | ### Checksummed Addresses All addresses must use **checksummed format** (EIP-55 mixed-case): - Authentication: `x-account` header - Orders: `maker` and `signer` fields - Example: `0x5aAeb6053F3E94C9b9A09f33669435E7Ef1BeAed` ### Implementation Guides **[🐍 Python Quick Start](#description/-python-quick-start)** - REST API: eth-account, requests, and web3.py libraries - WebSocket: python-socketio, asyncio integration **[☕ Java Quick Start](#description/-java-quick-start)** - REST API: Web3j, OkHttp3, and Jackson libraries **[📦 Node.js/TypeScript Quick Start](#description/-nodejs-typescript-quick-start)** - REST API: viem, ethers, and cross-fetch libraries - WebSocket: socket.io-client for real-time trading - Full TypeScript support with end-to-end examples **[🔌 WebSocket Integration](#description/-websocket-integration)** - Real-time market data and position updates - Production-ready Python client with authentication --- ## 🐍 Python Quick Start Complete end-to-end Python implementation for Limitless Exchange API integration. ### 🐍 Python E2E Order Creation Guide Complete Python implementation guide is being loaded from external documentation... **Guide Contents:** - 🔐 Complete authentication flow with eth-account - 📋 Order construction with Web3.py calculations - ✍️ EIP-712 structured data signing - 🚀 Order submission with requests library - ⚠️ Comprehensive error handling - 🛠️ Production deployment considerations *For the complete Python guide, ensure the file is available at docs/scripts-samples/python-e2e-order-creation.md* ## ☕ Java Quick Start Complete end-to-end Java implementation for Limitless Exchange API integration. ### ☕ Java E2E Order Creation Guide Complete Java enterprise implementation guide is being loaded from external documentation... **Guide Contents:** - 🔐 Complete authentication flow with Web3j - 📋 Order construction with BigInteger precision - ✍️ EIP-712 structured data signing - 🚀 Order submission with OkHttp3 - ⚠️ Enterprise error handling patterns - 🏗️ Production Maven project structure *For the complete Java guide, ensure the file is available at docs/scripts-samples/java-e2e-order-creation.md* ## 📦 Node.js/TypeScript Quick Start Complete end-to-end Node.js/TypeScript implementation for trading and WebSocket subscriptions. ### 📦 Node.js/TypeScript Trading & WebSocket Guide Complete Node.js/TypeScript implementation guide is being loaded from external documentation... **Guide Contents:** - 🔐 **Authentication**: Wallet-based auth with ethers and viem - 📋 **Order Creation**: EIP-712 signing with viem WalletClient - 🚀 **Order Submission**: REST API integration with cross-fetch - 🔌 **WebSocket Subscriptions**: socket.io-client for real-time updates - 📊 **Market Data**: AMM prices and CLOB orderbook subscriptions - ⚠️ **Type Safety**: Full TypeScript support with proper types - 🛠️ **Production Ready**: Complete end-to-end working example **Key Features:** - **Combined Subscriptions**: Subscribe to both AMM and CLOB markets simultaneously - **Authentication Flow**: Complete wallet-based authentication with session management - **Trading Integration**: Place orders and receive real-time updates - **TypeScript First**: Type-safe implementation with proper interfaces *For the complete Node.js guide, ensure the file is available at docs/scripts-samples/node-socket-trading-and-subscribe.md* ## 🔌 WebSocket Integration Real-time market data and position updates using WebSocket connections. ### 🔌 WebSocket Real-Time Integration Guide Complete WebSocket implementation guide is being loaded from external documentation... **Guide Contents:** - 🔌 **WebSocket Connection**: python-socketio client with async support - 🔐 **Authentication**: JWT session cookie integration - 📊 **Market Subscriptions**: Real-time price updates and position changes - ⚡ **Event Handling**: Comprehensive event processing patterns - 🔄 **Auto-Reconnection**: Production-ready reconnection logic - 🛠️ **Error Recovery**: Robust error handling and fallback strategies **Key Features:** - **Public Mode**: Market price updates without authentication - **Authenticated Mode**: Full access to positions and transactions - **Multi-Market Support**: Subscribe to multiple markets simultaneously - **Production Ready**: Tested patterns for production deployment *For the complete WebSocket guide, ensure the file is available at docs/scripts-samples/python-socket-subscribe.md* version: '1.0' contact: name: API Support url: https://limitless.exchange email: hey@limitless.network servers: - url: https://api.limitless.exchange description: Production API security: [] tags: - name: Authentication description: User authentication and session management - name: Markets description: Browse, search, and analyze prediction markets - name: Market Navigation description: Navigation tree, market pages, and property filters - name: Trading description: Create, manage, and cancel orders - name: Portfolio description: Position tracking, trade history, and performance - name: Feed description: Public trading activity feeds paths: /parlay/packs/{id}: get: tags: - Packs summary: Get a curated Pack description: >- Returns catalogue details. A returned Pack is not necessarily active or currently eligible; obtain a partner quote before buying. Hidden Packs return 404. operationId: ParlayController_getPack parameters: - name: id in: path required: true schema: type: string format: uuid responses: '200': description: Catalogue Pack content: application/json: schema: $ref: '#/components/schemas/PackResponseDto' '400': description: Invalid UUID '404': description: Pack not found or hidden security: [] components: schemas: PackResponseDto: type: object properties: id: type: string name: type: string parlayType: type: string enum: - CLOB - NEGRISK status: type: string enum: - ACTIVE - CLOSED - DRAFT - HIDDEN wasteStrategy: type: string enum: - HOLD - SELL description: Waste-disposition strategy for parlays bought from this pack earliestDeadline: type: string description: ISO timestamp of the earliest leg deadline legs: type: array items: $ref: '#/components/schemas/PackLegResponseDto' payout: description: Always computed with stake = "10" allOf: - $ref: '#/components/schemas/PackPayoutDto' properties: type: array items: $ref: '#/components/schemas/PackPropertyResponseDto' description: Property-key tags attached to this pack (used by filter pages) eligible: type: boolean description: >- True when the pack would be accepted by a quote against current orderbook state. False signals clients to disable the buy CTA and surface ineligibleReason. ineligibleReason: type: string nullable: true description: >- Single-line reason from the most recent quote attempt when eligible=false. Null when eligible. inDeadlineWindow: type: boolean description: >- Mirrors the deadline gate the active-pack listing applies. False packs are hidden from users even when ACTIVE. packOutcome: type: string enum: - WON - LOST - PENDING description: >- LOST the moment any resolved leg mismatches, WON only when every leg resolves matching, PENDING otherwise payoutCoefficient: type: number description: Catalogue payout coefficient. required: - id - name - parlayType - status - wasteStrategy - earliestDeadline - legs - payout - properties - inDeadlineWindow - packOutcome PackLegResponseDto: type: object properties: marketId: type: number marketSlug: type: string marketTitle: type: string marketType: type: string enum: - CLOB - NEGRISK nullable: true description: >- Per-leg market type (CLOB or NEGRISK); present for mixed-pack intent building outcome: type: string enum: - 'YES' - 'NO' livePrice: type: number description: Current market price (0..1) priceSnapshot: type: number description: Price at pack build time (0..1) group: nullable: true description: Group context for this leg (null for non-grouped markets) allOf: - $ref: '#/components/schemas/PackLegGroupDto' leagueName: type: string nullable: true description: Solo market's own league/discipline marketImageUrl: type: string nullable: true description: Logo/crest image URL from the leg market startMatchTimestamp: type: number nullable: true description: Solo market kickoff time (epoch seconds); null when not scheduled resolvedOutcome: type: string enum: - 'YES' - 'NO' nullable: true description: >- Actual on-chain market outcome. Null while the underlying market is unresolved. esportsPropType: type: string enum: - map_winner - map_handicap - total_maps nullable: true description: >- Which typed esports prop this leg is, so it can be drawn as a prop of a fixture rather than as the fixture. Null on match winners and on every non-esports market. outcomeLabels: type: array nullable: true minItems: 2 maxItems: 2 items: type: string description: >- For named-outcome markets: labels as [homeTeam/YES, awayTeam/NO]. Null when labels are unavailable. outcomeImageUrls: type: array nullable: true minItems: 2 maxItems: 2 items: type: string nullable: true description: >- Outcome-specific artwork as [homeTeam/YES, awayTeam/NO]. Null when no artwork is available. required: - marketId - marketSlug - marketTitle - outcome - livePrice - priceSnapshot - resolvedOutcome - esportsPropType - outcomeLabels - outcomeImageUrls PackPayoutDto: type: object properties: stake: type: string description: Display stake in dollars example: '10' parlayMultiplier: type: number description: Parlay multiplier after vig (4dp) parlayPayout: type: string description: Parlay payout in dollars (2dp) example: '76.80' singlesMultiplier: type: number description: Average singles multiplier (4dp) singlesPayout: type: string description: Singles payout in dollars, stake split equally across legs (2dp) savingsPct: type: number description: Savings percent vs singles required: - stake - parlayMultiplier - parlayPayout - singlesMultiplier - singlesPayout - savingsPct PackPropertyResponseDto: type: object properties: id: type: string description: Pack property row id propertyKeyId: type: string description: Property key UUID propertyKeySlug: type: string description: Property key slug (e.g. "domain") propertyKeyName: type: string description: Property key name value: description: Value for this pack required: - id - propertyKeyId - propertyKeySlug - propertyKeyName - value PackLegGroupDto: type: object properties: id: type: number slug: type: string title: type: string leagueName: type: string nullable: true description: Match group's league/discipline homeTeam: type: string nullable: true awayTeam: type: string nullable: true homeScore: type: number nullable: true awayScore: type: number nullable: true startMatchTimestamp: type: number nullable: true description: Match kickoff time (epoch seconds); null for non-sports groups required: - id - slug - title ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.