— name: polymarket description: Query Polymarket prediction market data — search markets, get prices, orderbooks, and price history. Read-only via public REST APIs, no API key needed. version: 1.0.0 author: Hermes Agent + Teknium tags: [polymarket, prediction-markets, market-data, trading] — # Polymarket — Prediction Market Data Query prediction market data from Polymarket using their public REST APIs. All endpoints are read-only and require zero authentication. See `references/api-endpoints.md` for the full endpoint reference with curl examples. ## When to Use – User asks about prediction markets, betting odds, or event probabilities – User wants to know "what are the odds of X happening?" – User asks about Polymarket specifically – User wants market prices, orderbook data, or price history – User asks to monitor or track prediction market movements ## Key Concepts – **Events** contain one or more **Markets** (1:many relationship) – **Markets** are binary outcomes with Yes/No prices between 0.00 and 1.00 – Prices ARE probabilities: price 0.65 means the market thinks 65% likely – `outcomePrices` field: JSON-encoded array like `["0.80", "0.20"]` – `clobTokenIds` field: JSON-encoded array of two token IDs [Yes, No] for price/book queries – `conditionId` field: hex string used for price history queries – Volume is in USDC (US dollars) ## Three Public APIs 1. **Gamma API** at `gamma-api.polymarket.com` — Discovery, search, browsing 2. **CLOB API** at `clob.polymarket.com` — Real-time prices, orderbooks, history 3. **Data API** at `data-api.polymarket.com` — Trades, open interest ## Typical Workflow When a user asks about prediction market odds: 1. **Search** using the Gamma API public-search endpoint with their query 2. **Parse** the response — extract events and their nested markets 3. **Present** market question, current prices as percentages, and volume 4. **Deep dive** if asked — use clobTokenIds for orderbook, conditionId for history ## Presenting Results Format prices as percentages for readability: – outcomePrices `["0.652", "0.348"]` becomes "Yes: 65.2%, No: 34.8%" – Always show the market question and probability – Include volume when available Example: `"Will X happen?" — 65.2% Yes ($1.2M volume)` ## Parsing Double-Encoded Fields The Gamma API returns `outcomePrices`, `outcomes`, and `clobTokenIds` as JSON strings inside JSON responses (double-encoded). When processing with Python, parse them with `json.loads(market['outcomePrices'])` to get the actual array. ## Rate Limits Generous — unlikely to hit for normal usage: – Gamma: 4,000 requests per 10 seconds (general) – CLOB: 9,000 requests per 10 seconds (general) – Data: 1,000 requests per 10 seconds (general) ## Limitations – This skill is read-only — it does not support placing trades – Trading requires wallet-based crypto authentication (EIP-712 signatures) – Some new markets may have empty price history – Geographic restrictions apply to trading but read-only data is globally accessible