Polymarket Knowledge

Overview

Comprehensive reference for Polymarket CLOB API integration, focusing on order management and real-time event handling.

Quick Reference

Order Types

Type Behavior Use Case

GTC Good Till Cancelled Maker orders, liquidity provision

GTD Good Till Date Time-limited orders

FOK Fill Or Kill Must fill completely or cancel

FAK Fill And Kill Fill what you can, cancel rest

Order Requirements

• Minimum order value: $1 USDC

• Minimum shares: 5

• Tick size: 0.01 (prices must be 0.01, 0.02, ... 0.99)

Order State Machine

See references/order-state-machine.md for complete state diagram and transitions.

States: PENDING → OPEN → PARTIALLY_FILLED → FILLED/CANCELLED/EXPIRED

API Status Mapping:

• live → OPEN

• matched (partial) → PARTIALLY_FILLED

• matched (full) → FILLED

• delayed → PENDING

• cancelled → CANCELLED

• expired → EXPIRED

WebSocket Events

See references/websocket-events.md for field mappings and examples.

Key Endpoints:

• Market: wss://ws-subscriptions-clob.polymarket.com/ws/market

• User: wss://ws-subscriptions-clob.polymarket.com/ws/user (authenticated)

USER_ORDER Event Types: PLACEMENT, UPDATE, CANCELLATION USER_TRADE Statuses: MATCHED, MINED, CONFIRMED, RETRYING, FAILED

Common Pitfalls

• Wrong field names: API uses matched_amount not matched_size , size_matched not matched_size

• Wrong endpoint: USER events require /ws/user , not /ws/market

• USDC type: Polymarket uses USDC.e (bridged), not native USDC

Resources

• references/order-state-machine.md - State transitions and validation

• references/websocket-events.md - WebSocket field mappings

• references/api-field-mappings.md - API response field reference