polymarket-mcp

pip install polymarket-mcp

MCP server and Python toolkit for Polymarket prediction markets. Gives AI agents real-time slippage estimation, liquidity scanning, arbitrage detection, crypto price feeds, contract timers, sentiment analysis, probability estimation, and portfolio risk calculation — all through the Model Context Protocol.

Works with Claude Desktop, Cursor, Windsurf, and any MCP-compatible client.

Quick Start

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "polymarket": {
      "command": "polymarket-mcp",
      "args": ["--stdio"]
    }
  }
}

Run as SSE server

polymarket-mcp
# Starts on http://127.0.0.1:8000/sse

Run as streamable HTTP

polymarket-mcp --http
# Starts on http://127.0.0.1:8000/mcp

Tools

All free tools require no API key. Paid tools require an API key from whitmorelabs.io.

Free Tools

estimate_slippage

Walk the CLOB order book and calculate average fill price for a given position size.

estimate_slippage(
    market_id="71321045679252212594626385532587807886473352341859285086426388424842616389328",
    side="BUY",
    position_size_usd=500.0
)

Returns: best_price, avg_fill_price, slippage_pct, liquidity_available, recommendation (go/caution/no-go).

scan_market_liquidity

Scan a market's liquidity depth with spread and depth at 1%/2%/5% from mid.

scan_market_liquidity(market_id="71321045679252212594626385532587807886473352341859285086426388424842616389328")

Returns: best_bid, best_ask, spread_pct, depth buckets, liquidity_grade (A/B/C).

find_arbitrage_gaps

Scan all active Polymarket markets for YES + NO price sums that don't equal 1.00.

find_arbitrage_gaps(min_gap_pct=2.0)

Returns: markets with gaps, gap size, and direction to exploit (BUY_BOTH or SELL_BOTH).

get_crypto_price

Real-time crypto price from Binance and/or CoinGecko in parallel, with latency metadata.

get_crypto_price(symbol="BTC", sources="binance,coingecko")

Returns: per-source prices, average, max deviation between sources.

get_contract_status

Time remaining and resolution status for active Polymarket contracts. BTC 5-min/15-min contracts use slug timestamp parsing for exact expiry.

get_contract_status(market_id="btc-updown-5m-1711234567")
get_contract_status(category="crypto")  # scan all short-duration contracts

Returns: time_remaining_seconds, time_remaining_human, current_odds.

estimate_probability

Estimate the probability of any event using structured reasoning. Base rates, key factors, timeframe analysis — all in one structured JSON response.

estimate_probability(question="Will Bitcoin reach $150k before end of 2025?")

Returns: estimated_probability (0-1), confidence_level, factors_for, factors_against, base_rate_note, reasoning.

calculate_portfolio_risk

Pure-math risk metrics for a portfolio of prediction market positions. No external API calls.

calculate_portfolio_risk(positions='[{"market_id": "abc123", "side": "YES", "size": 200, "entry_price": 0.65}]')

Returns: total_exposure, max_loss, max_gain, diversification_score, kelly_warnings, rebalancing_suggestions.

get_scoring_performance

Free. No API key. Returns scoring methodology, current dataset stats, and pricing. Call this first to evaluate whether the paid data is worth it.

Paid Tools (API key required)

7-day free trial on signup. After trial: pay-per-request in USDC on Polygon.

Volume discount: 50% off above 1000 requests/day.

get_shadow_wallets

Find wallets that co-trade with a seed wallet across the same Polymarket categories.

get_shadow_wallets(seed_wallet="0xabc...", api_key="your-key")

Returns: up to 20 shadow wallets ranked by co-trading intensity, shared categories, win rates.

get_top_wallets

Top-ranked Polymarket wallets from MoonMirror's scoring engine (PnL + consistency + specialization - drawdown penalty).

get_top_wallets(api_key="your-key", limit=50, min_score=0.5)

get_wallet_score

Full scoring breakdown for a specific wallet address.

get_wallet_score(address="0xabc...", api_key="your-key")

Returns: score components, win rate, trade count, data freshness.

get_wallet_pnl

Realized PnL for a wallet with per-category breakdown. Pre-computed from Goldsky subgraph.

get_wallet_pnl(address="0xabc...", api_key="your-key")

get_wallet_clusters

Wallets that independently appear alongside 3+ different top-scoring wallets — stronger signal than a single shadow match.

get_wallet_clusters(api_key="your-key", min_co_trades=3)

get_btc_short_markets

Active BTC 5-min and 15-min Polymarket contracts with token IDs and current midpoint prices. Cached, refreshed every 60 seconds.

get_btc_short_markets(api_key="your-key")

analyze_market_sentiment

Structured probabilistic analysis for a prediction market question using Claude's reasoning.

analyze_market_sentiment(question="Will Ethereum ETF hit $10B AUM by Q3 2025?", api_key="your-key")

Wallet Intelligence: How It Works

The paid wallet tools are backed by MoonMirror, a Polymarket wallet intelligence engine. MoonMirror continuously monitors wallets on-chain, scores them on PnL, consistency, and market specialization, and pre-computes shadow wallet relationships.

All wallet queries return in < 100ms because everything is pre-computed. No blocking subgraph calls.

Alternatives Comparison

Configuration

All settings via environment variables:

# Server
HOST=127.0.0.1
PORT=8000

# DB paths (for self-hosted wallet intelligence)
MOONMIRROR_DB_PATH=/path/to/moonmirror.db
SERVICES_DB_PATH=/path/to/services.db

# Pricing
PRICE_WALLET_INTEL=0.05
PRICE_MARKET_DATA=0.01
TRIAL_DAYS=7

# Rate limiting
RATE_PER_KEY=5
RATE_GLOBAL=20

Admin CLI

# Create an API key
polymarket-mcp --create-key "customer-name"

# Top up a key's USDC balance
polymarket-mcp --top-up YOUR_KEY 10.0

GitHub

github.com/whitmorelabs/polymarket-mcp

Issues, PRs, and stars welcome.