> ## 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.
# Browse Active Markets by Category
> Retrieves markets and groups that are active and not yet resolved, with optional category filtering
This is the same as [Browse Active Markets](/api-reference/markets/browse-active) but with the category ID as a path parameter instead of a query parameter. Use [Get Category Counts](/api-reference/markets/category-count) to discover available category IDs.
Supports `includeNextMarket=true` for upfront-scheduled successor navigation. See [Browse Active Markets](/api-reference/markets/browse-active) for the response shape and usage guidance.
## OpenAPI
````yaml GET /markets/active/{categoryId}
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:
/markets/active/{categoryId}:
get:
tags:
- Markets
summary: Browse Active Markets
description: >-
Retrieves markets and groups that are active and not yet resolved, with
optional category filtering
operationId: MarketController_getActiveMarkets[0]
parameters:
- name: page
required: false
in: query
description: Page number for pagination
schema:
type: number
example: 1
- name: limit
required: false
in: query
description: Number of items per page
schema:
example: 10
type: number
- name: sortBy
required: false
in: query
description: Sort by query parameter
schema:
$ref: '#/components/schemas/Object'
- name: tradeType
required: false
in: query
description: Filter by trade type (amm, clob, or group)
schema:
enum:
- amm
- clob
- group
type: string
- name: automationType
required: false
in: query
description: Filter by automation type (manual, lumy, or sports)
schema:
enum:
- manual
- lumy
- sports
type: string
- name: includeNextMarket
required: false
in: query
description: Include upfront-scheduled successor navigation
schema:
type: boolean
- name: categoryId
required: true
in: path
description: Filter markets by category ID
schema:
type: number
responses:
'200':
description: Active markets and groups with volume and liquidity data
content:
application/json:
schema:
$ref: '#/components/schemas/BrowseActiveMarketsResponseDto'
'500':
description: Server error when retrieving markets data
components:
schemas:
Object:
type: object
properties: {}
BrowseActiveMarketsResponseDto:
type: object
properties:
data:
type: array
description: >-
Array of active markets with complete trading data including volume,
liquidity, and recent feed events
example:
- id: 7495
address: '0x76d3e2098Be66Aa7E15138F467390f0Eb7349B9b'
conditionId: >-
0x812f578437dc536def1412e4e593ef310884262c22868b30c1e58582e5f3e9bf
title: DOGE Up or Down - Hourly
description: >-
This market will resolve to "Up" if the price of DOGE is above
the opening price...
collateralToken:
address: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
decimals: 6
symbol: USDC
creator:
name: Limitless
imageURI: https://limitless.exchange/assets/images/logo.svg
link: https://x.com/trylimitless
prices:
- 42.8
- 57.2
categories:
- Hourly
tags:
- Lumy
- Recurring
- Hourly
- Simple Mode
status: FUNDED
expired: false
expirationDate: Sep 1, 2025
expirationTimestamp: 1756728000000
volume: '164109293'
volumeFormatted: '164.109293'
openInterest: '48310707'
openInterestFormatted: '48.310707'
liquidity: '50000000'
liquidityFormatted: '50.000000'
tradeType: amm
marketType: single
slug: doge-up-or-down-1-hour-1756724413009
feedEvents:
- eventType: NEW_TRADE
timestamp: '2025-09-01T11:30:31.000Z'
user:
id: 7080
account: '0xea27f6788F083e6070961d3E52A2e596367E04CC'
name: GG
rankName: Bronze
points: '0.00000000'
data:
title: DOGE Up or Down - Hourly
address: '0x76d3e2098Be66Aa7E15138F467390f0Eb7349B9b'
strategy: Buy
outcome: Down
contracts: '9.071313'
tradeAmount: '5'
tradeAmountUSD: '4.999525'
marketId: 7495
items:
type: object
description: Market object with complete trading data (FEMarket type)
additionalProperties: true
totalMarketsCount:
type: number
description: Total number of active markets available for pagination
example: 150
required:
- data
- totalMarketsCount
````