Polymarket Copy Trading Bot Skill by ara.so — Daily 2026 Skills collection. A TypeScript bot that continuously monitors a target Polymarket wallet, detects trades in real time via REST polling and/or WebSocket, and mirrors BUY orders to your own account using the Polymarket CLOB SDK on Polygon mainnet. What It Does Monitors a target wallet via Polymarket Data API (REST polling every ~2s) and optionally WebSocket Mirrors BUY trades only — SELL trades are detected but skipped by default Sizes copies using a configurable POSITION_MULTIPLIER (default 10%) with min/max caps Submits orders as FOK, FAK, or LIMIT via the Polymarket CLOB client Enforces risk limits — per-session and per-market notional caps Supports three auth modes — EOA ( SIG_TYPE=0 ), Poly Proxy ( SIG_TYPE=1 ), Poly Polymorphic ( SIG_TYPE=2 ) Installation git clone https://github.com/Neron888/Polymarket-copy-trading-bot.git cd Polymarket-copy-trading-bot npm install Requires Node.js v18+. The CLOB SDK requires ethers v5 (already pinned in package.json ). Configuration cp .env.example .env Edit .env :

Required

TARGET_WALLET=0xTargetWalletAddressToMonitor WALLET_PRIVATE_KEY=0xYourPrivateKey RPC_URL=https://your-quicknode-polygon-endpoint.quiknode.pro/your-key/

Auth mode (0=EOA default, 1=Poly Proxy, 2=Poly Polymorphic)

SIG_TYPE=0

Required only for SIG_TYPE=1 or 2

PROXY_WALLET_ADDRESS=

Sizing

POSITION_MULTIPLIER=0.1 # 10% of target's trade size MAX_TRADE_SIZE=100 # Max USDC per copied trade MIN_TRADE_SIZE=1 # Min USDC per copied trade

Order behavior

ORDER_TYPE=FOK # FOK | FAK | LIMIT SLIPPAGE_TOLERANCE=0.02 # 2%

Risk caps (0 = disabled)

MAX_SESSION_NOTIONAL=500 # Total USDC for entire session MAX_PER_MARKET_NOTIONAL=100 # Per market USDC cap

Monitoring

USE_WEBSOCKET=true POLL_INTERVAL=2000 # ms between REST polls USE_USER_CHANNEL=false # true = user WS channel, false = market channel

Optional

POLYMARKET_GEO_TOKEN= WS_ASSET_IDS= # comma-separated asset IDs for market WS WS_MARKET_IDS= # comma-separated condition IDs for user channel MIN_PRIORITY_FEE_GWEI=30 MIN_MAX_FEE_GWEI=60 Key Commands

Start the bot (development mode with ts-node)

npm start

Generate and persist API credentials to .polymarket-api-creds

npm run generate-api-creds

Validate existing API credentials

npm run test-api-creds

Compile TypeScript to dist/

npm run build

Run compiled production build

npm run start:prod Architecture Overview index.ts └── TradeMonitor — REST polls Polymarket Data API for new target trades └── WebSocketMonitor — Optional low-latency WS subscription (market or user channel) └── TradeExecutor — Sizes trade, checks balance/allowance, submits CLOB order └── PositionTracker — In-memory positions updated on fills └── RiskManager — Session + per-market notional enforcement Execution flow: detect trade → BUY? → subscribe WS if needed → compute copy size → risk check → execute order (FOK/FAK/LIMIT) → record fill → update stats Code Examples Starting the bot programmatically import { startBot } from './src/index' ; // The bot reads all config from process.env / .env startBot ( ) ; TradeMonitor — polling pattern import { TradeMonitor } from './src/TradeMonitor' ; const monitor = new TradeMonitor ( { targetWallet : process . env . TARGET_WALLET ! , pollInterval : Number ( process . env . POLL_INTERVAL ?? 2000 ) , } ) ; monitor . on ( 'trade' , ( trade ) => { console . log ( 'New trade detected:' , trade ) ; // trade.side: 'BUY' | 'SELL' // trade.asset: token ID (outcome token address) // trade.size: USDC size // trade.price: fill price (0–1) } ) ; monitor . start ( ) ; TradeExecutor — placing a copy order import { TradeExecutor } from './src/TradeExecutor' ; import { ClobClient } from '@polymarket/clob-client' ; import { ethers } from 'ethers' ; const provider = new ethers . providers . JsonRpcProvider ( process . env . RPC_URL ) ; const signer = new ethers . Wallet ( process . env . WALLET_PRIVATE_KEY ! , provider ) ; const clobClient = new ClobClient ( 'https://clob.polymarket.com' , 137 , // Polygon chainId signer , apiCreds , // loaded from .polymarket-api-creds Number ( process . env . SIG_TYPE ?? 0 ) , process . env . PROXY_WALLET_ADDRESS || undefined , ) ; const executor = new TradeExecutor ( { client : clobClient , positionMultiplier : Number ( process . env . POSITION_MULTIPLIER ?? 0.1 ) , maxTradeSize : Number ( process . env . MAX_TRADE_SIZE ?? 100 ) , minTradeSize : Number ( process . env . MIN_TRADE_SIZE ?? 1 ) , orderType : ( process . env . ORDER_TYPE ?? 'FOK' ) as 'FOK' | 'FAK' | 'LIMIT' , slippageTolerance : Number ( process . env . SLIPPAGE_TOLERANCE ?? 0.02 ) , } ) ; // Copy a detected trade await executor . copyTrade ( { side : 'BUY' , tokenId : '0xAssetId...' , originalSize : 12.5 , // USDC from target's trade price : 0.62 , } ) ; RiskManager — checking before execution import { RiskManager } from './src/RiskManager' ; const riskManager = new RiskManager ( { maxSessionNotional : Number ( process . env . MAX_SESSION_NOTIONAL ?? 0 ) , maxPerMarketNotional : Number ( process . env . MAX_PER_MARKET_NOTIONAL ?? 0 ) , } ) ; const allowed = riskManager . checkTrade ( { marketId : '0xConditionId...' , notional : copySize , } ) ; if ( ! allowed ) { console . log ( 'Trade blocked by risk limits' ) ; } WebSocket monitor — low-latency subscription import { WebSocketMonitor } from './src/WebSocketMonitor' ; const wsMonitor = new WebSocketMonitor ( { useUserChannel : process . env . USE_USER_CHANNEL === 'true' , assetIds : process . env . WS_ASSET_IDS ?. split ( ',' ) . filter ( Boolean ) ?? [ ] , marketIds : process . env . WS_MARKET_IDS ?. split ( ',' ) . filter ( Boolean ) ?? [ ] , } ) ; wsMonitor . on ( 'orderFilled' , ( fill ) => { console . log ( 'Fill received via WS:' , fill ) ; } ) ; wsMonitor . connect ( ) ; Authentication Modes EOA (default — SIG_TYPE=0 ) SIG_TYPE=0 WALLET_PRIVATE_KEY=0xYourKey

PROXY_WALLET_ADDRESS — leave empty

On first run, the bot auto-submits USDC.e/CTF approval transactions. Wallet needs POL for gas. Poly Proxy ( SIG_TYPE=1 ) SIG_TYPE=1 WALLET_PRIVATE_KEY=0xSignerKey PROXY_WALLET_ADDRESS=0xYourPolymarketProxyAddress Poly Polymorphic ( SIG_TYPE=2 ) SIG_TYPE=2 WALLET_PRIVATE_KEY=0xSignerKey PROXY_WALLET_ADDRESS=0xYourPolymorphicSafeAddress Generating API Credentials npm run generate-api-creds This derives API keys from your wallet signature and writes them to .polymarket-api-creds . Run once before npm start if you want to pre-generate credentials. The bot also auto-generates them on first start in EOA mode. Validate credentials: npm run test-api-creds Common Patterns Conservative testing setup POSITION_MULTIPLIER=0.05 MAX_TRADE_SIZE=5 MIN_TRADE_SIZE=1 MAX_SESSION_NOTIONAL=20 ORDER_TYPE=FOK USE_WEBSOCKET=false WebSocket-only market channel (lower latency) USE_WEBSOCKET=true USE_USER_CHANNEL=false WS_ASSET_IDS=0xTokenId1,0xTokenId2 LIMIT orders with slippage buffer ORDER_TYPE=LIMIT SLIPPAGE_TOLERANCE=0.03 Troubleshooting Bot starts but no trades detected Verify TARGET_WALLET is a valid Polymarket wallet with recent activity Check POLL_INTERVAL — default 2000ms; lower means more API calls Confirm the target wallet trades on Polymarket (not just holds positions) ethers version conflicts The project pins ethers v5. Do not upgrade to v6 — the CLOB SDK requires v5 Run npm ls ethers to check for duplicate versions Approval transactions failing Ensure the wallet has sufficient POL (MATIC) for gas on Polygon mainnet Try increasing MIN_PRIORITY_FEE_GWEI and MIN_MAX_FEE_GWEI if transactions stall generate-api-creds fails Confirm WALLET_PRIVATE_KEY is correct and 0x-prefixed For SIG_TYPE=1/2 , ensure PROXY_WALLET_ADDRESS matches your Polymarket account Orders rejected by CLOB FOK orders fail if insufficient liquidity — try ORDER_TYPE=FAK or LIMIT Check SLIPPAGE_TOLERANCE isn't too tight for illiquid markets Session notional cap hit immediately MAX_SESSION_NOTIONAL resets per process run; restart the bot to reset Set MAX_SESSION_NOTIONAL=0 to disable the cap entirely Wallet Requirements USDC.e on Polygon mainnet (collateral for trades) POL (formerly MATIC) for gas fees Approve USDC.e for Polymarket CTF Exchange and CLOB contracts (bot does this automatically on first EOA run) References QuickNode Guide — Building a Polymarket Copy Trading Bot Polymarket CLOB Client SDK Polymarket Polymarket CLOB API Docs