polymarket-prediction-market

Understand Polymarket’s prediction markets—binary event contracts, CLOB pricing, order books, conditional tokens, and API integration.

Allowed Tools

• Read
• Grep
• Glob
• WebFetch

Core Mental Model

Polymarket operates as a decentralized prediction market on Polygon using USDC:

• Binary Outcomes: Each market has YES and NO tokens that settle at $1.00 or $0.00
• Price = Probability: A YES token at $0.65 implies 65% probability of the outcome
• CLOB (Central Limit Order Book): Prices determined by limit orders, not AMM
• Conditional Token Framework (CTF): Outcomes represented as ERC-1155 tokens
• USDC Collateral: All trading uses USDC on Polygon network

Data Hierarchy

Condition (Event)
  └── Market
        ├── YES Token (token_id)
        └── NO Token (token_id)

• Condition: The overarching question/event (e.g., “Will Team Liquid win?”)
• Market: A specific tradeable contract with YES/NO outcomes
• Tokens: Each outcome is a separate ERC-1155 token with unique token_id

Market Objects

Key fields in Polymarket market data:

Order Book Structure

Polymarket uses a Central Limit Order Book (CLOB):

Order Book for "YES" Token
--------------------------
BIDS (Buy Orders)     |  ASKS (Sell Orders)
$0.62 - 500 shares    |  $0.64 - 300 shares
$0.61 - 1000 shares   |  $0.65 - 800 shares
$0.60 - 2000 shares   |  $0.66 - 1500 shares

• Bid: Highest price buyers will pay
• Ask: Lowest price sellers will accept
• Spread: Difference between best bid and ask
• Mid Price: (Best Bid + Best Ask) / 2

Trading Mechanics

Order Types

Position Management

• Buy YES: Profit if outcome is true (settles at $1.00)
• Buy NO: Profit if outcome is false (settles at $1.00)
• Sell: Close position by selling tokens back to order book
• Merge: Combine YES + NO tokens to redeem $1.00 USDC

Fees

• Maker Fee: ~0% (providing liquidity)
• Taker Fee: ~1-2% (taking liquidity)
• Fees may vary; check current fee schedule

Settlement & Resolution

1. Trading Closes: Market stops accepting orders at end_date_iso
2. Resolution: Oracle determines the outcome
3. Settlement:
   • Winning tokens redeem for $1.00 USDC
   • Losing tokens become worthless ($0.00)
4. Redemption: Users claim winnings via smart contract

API Conventions

Base URLs

Public Endpoints (No Auth)

Authenticated Endpoints

Authentication

Polymarket uses EIP-712 signatures for authentication:

Headers:
  POLY_ADDRESS: <wallet_address>
  POLY_SIGNATURE: <eip712_signature>
  POLY_TIMESTAMP: <unix_timestamp>
  POLY_NONCE: <random_nonce>

WebSocket (Real-time Updates)

Connect to wss://ws-subscriptions-clob.polymarket.com/ws/ for:

• price – Real-time price updates
• book – Order book changes
• trades – Trade execution notifications

API Response Examples

Market Object

{
  "condition_id": "0x1234...",
  "question": "Will Team Liquid win the CS2 Major?",
  "tokens": [
    {
      "token_id": "12345",
      "outcome": "Yes",
      "price": 0.65
    },
    {
      "token_id": "12346",
      "outcome": "No",
      "price": 0.35
    }
  ],
  "volume": "150000.00",
  "liquidity": "25000.00",
  "end_date_iso": "2024-03-15T00:00:00Z",
  "active": true,
  "closed": false
}

Order Book Response

{
  "token_id": "12345",
  "bids": [
    {"price": "0.64", "size": "500"},
    {"price": "0.63", "size": "1000"}
  ],
  "asks": [
    {"price": "0.66", "size": "300"},
    {"price": "0.67", "size": "800"}
  ]
}

Sports & Esports Markets

Polymarket hosts various sports and esports betting markets. Understanding the naming conventions and market structures is critical for matching markets across platforms.

Supported Categories

Market Naming Conventions

Polymarket sports markets typically follow these patterns:

Match Winner:
  "Will [Team A] beat [Team B]?"
  "Will [Team A] win against [Team B]?"
  "[Team A] vs [Team B] - Winner"

Tournament Winner:
  "Will [Team/Player] win [Tournament]?"
  "[Tournament] Winner: [Team/Player]"

Player Props:
  "Will [Player] score [X] points?"
  "Will [Player] get [X] kills?"

Common Name Variations

When matching markets across platforms, watch for these variations:

Esports-Specific Patterns

CS2 (Counter-Strike 2)

Market formats:
  "Will Team Liquid win vs FaZe Clan?"
  "Team Liquid vs FaZe - CS2 Major"
  "CS2 Major Champion: Team Liquid"

Common tournaments:
  - Major Championships (Copenhagen, Shanghai)
  - ESL Pro League
  - BLAST Premier
  - IEM (Intel Extreme Masters)

League of Legends

Market formats:
  "Will T1 win Worlds 2024?"
  "T1 vs Gen.G - LCK Finals"
  "League of Legends World Champion"

Common tournaments:
  - Worlds (World Championship)
  - MSI (Mid-Season Invitational)
  - LCK, LEC, LCS (Regional leagues)

Valorant

Market formats:
  "Will Sentinels win VCT Champions?"
  "Sentinels vs LOUD - VCT Finals"

Common tournaments:
  - VCT Champions
  - VCT Masters
  - Regional Challengers

Call of Duty

Market formats:
  "Will OpTic win CDL Championship?"
  "OpTic vs FaZe - CDL Major"

Common tournaments:
  - CDL (Call of Duty League) Majors
  - CDL Championship
  - Warzone events

Traditional Sports Patterns

NBA Basketball

Market formats:
  "Will the Lakers beat the Celtics?"
  "Lakers vs Celtics - NBA Finals Game 1"
  "NBA Champion 2024"

Identifiers:
  - Team city + name (Los Angeles Lakers)
  - Just team name (Lakers)
  - Abbreviations (LAL)

Soccer/Football

Market formats:
  "Will Manchester City beat Arsenal?"
  "Man City vs Arsenal - Premier League"
  "Champions League Winner 2024"

Leagues/Tournaments:
  - Premier League (England)
  - La Liga (Spain)
  - Serie A (Italy)
  - Bundesliga (Germany)
  - UEFA Champions League
  - UEFA Europa League
  - World Cup

NFL Football

Market formats:
  "Will the Chiefs beat the Eagles?"
  "Chiefs vs Eagles - Super Bowl"
  "Super Bowl LVIII Winner"

Identifiers:
  - City + name (Kansas City Chiefs)
  - Just name (Chiefs)
  - Abbreviations (KC)

Tennis

Market formats:
  "Will Djokovic win Wimbledon?"
  "Djokovic vs Alcaraz - Wimbledon Final"
  "US Open Men's Singles Winner"

Tournaments:
  - Grand Slams: Australian Open, French Open, Wimbledon, US Open
  - ATP/WTA Masters events

MMA/UFC

Market formats:
  "Will Jon Jones beat Stipe Miocic?"
  "Jones vs Miocic - UFC 309"
  "UFC Heavyweight Champion after UFC 309"

Identifiers:
  - Fighter full name
  - Last name only
  - Nickname ("Bones" for Jon Jones)

API Filtering for Sports Markets

To find sports markets programmatically:

// Filter by tags/categories
GET /markets?tag=sports
GET /markets?tag=esports
GET /markets?tag=nba
GET /markets?tag=cs2

// Search by keywords in question
GET /markets?search=NBA
GET /markets?search=Team%20Liquid
GET /markets?search=UFC

// Filter active sports markets
GET /markets?active=true&tag=sports

Market Matching Strategy

For cross-platform arbitrage, use this matching approach:

1. Normalize team/player names

   • Remove special characters: FaZe Clan → faze clan
   • Handle abbreviations: TL → team liquid
   • Map nicknames: NaVi → natus vincere

2. Extract key entities

   • Team A name
   • Team B name
   • Tournament/League name
   • Match date/time

3. Match by similarity

   • Levenshtein distance for fuzzy matching
   • Token overlap for multi-word names
   • Date proximity for same matchup

4. Verify market type

   • Both markets must be “match winner” type
   • Same teams/players involved
   • Same event timeframe

Example: Cross-Platform Match

Polymarket Market:
  Question: "Will Team Liquid beat G2 Esports?"
  YES price: $0.55
  End date: 2024-03-15

Kalshi Market:
  Title: "Team Liquid vs G2 - CS2 Major Semifinal"
  YES price: $0.52
  NO price: $0.51

Matching confidence: HIGH
- Same teams (Team Liquid, G2)
- Similar timeframe
- Both match-winner markets

Arbitrage check:
  Polymarket NO: $0.45
  Kalshi YES: $0.52
  Total: $0.97 → $0.03 profit potential

Application Guidance

When answering questions about Polymarket:

1. Clarify terminology: Explain that prices represent implied probabilities
2. Highlight CLOB: Unlike AMMs, Polymarket uses limit orders
3. Explain tokens: YES/NO are separate tradeable ERC-1155 tokens
4. Note fees: Taker fees reduce profit margins
5. Mention settlement: Winning tokens redeem at exactly $1.00
6. Stay neutral: Do not provide financial advice or predictions

Arbitrage Context (ArbiBot)

For cross-platform arbitrage with Kalshi:

Valid Arbitrage Strategy

Buy opposing outcomes across platforms when total cost < $1.00:

Example:
  Polymarket YES @ $0.45
  Kalshi NO @ $0.48
  Total Cost: $0.93
  Guaranteed Profit: $0.07 (one side pays $1.00)

Examples

Explaining a Price

“The YES token trading at $0.72 means the market collectively estimates a 72% probability of this outcome occurring.”

Describing Order Execution

“Your limit order to buy 100 YES shares at $0.65 will sit in the order book until someone sells at that price or lower.”

Settlement Explanation

“If Team Liquid wins, your YES tokens settle at $1.00 each. If they lose, those tokens become worthless, but any NO tokens would pay out $1.00.”

References

• Polymarket CLOB Documentation
• Polymarket API Reference
• Conditional Token Framework