polymarket

Retrieve Polymarket event probabilities and format Yes/No outcome prices.

Updated May 4, 2026

Search Tags:#market data #orderbook #polymarket #price history #json parsing #prediction markets #market odds

Ready to run

npx skills add https://github.com/JamesFincher/gengar --skill polymarket-jamesfincher

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: polymarket
Source: https://github.com/JamesFincher/gengar/tree/main/skills/research/polymarket
Command: npx skills add https://github.com/JamesFincher/gengar --skill polymarket-jamesfincher

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

Polymarket users need fast, reliable access to prediction market odds and supporting market context without setting up authenticated trading integrations.

Core Features & Use Cases

Read-only market discovery and lookup: Search events and retrieve markets to answer questions like “What are the odds of X?”
Probability-first pricing: Present Yes/No outcome prices as percentages (e.g., 0.65 → 65.0%) along with available volume.
Deeper market data on demand: Use CLOB tokens for orderbooks and condition IDs for price history, and optionally consult the trades/open-interest feeds.
Use case: When someone asks “Will it happen?” the Skill can summarize the matching event, show current Yes/No probabilities, and include liquidity/volume context when available.

Quick Start

Ask for “Polymarket odds for bitcoin ETF approval” to retrieve the most relevant matching event and its current Yes/No probabilities.

Frequently Asked Questions about polymarket

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I get prediction market odds for a specific event?▼

To get prediction market odds, you search and retrieve Polymarket events and markets, then format outcome probability prices for interpretation. The skill presents Yes/No outcome prices as percentages along with available volume.

What is the best way to retrieve orderbook details and price history from prediction markets?▼

The best way to retrieve orderbook details and price history is by using CLOB tokens for orderbooks and condition IDs for price history feeds. You query public REST GET calls to the Gamma, CLOB, and Data APIs.

How does parsing double-encoded JSON fields work when querying Polymarket APIs?▼

Parsing double-encoded JSON fields works by decoding nested JSON strings within fields like outcomePrices and clobTokenIds returned by Polymarket REST APIs. This extraction is required to access underlying market pricing data.

Can I use this to check prediction market odds without setting up authenticated trading integrations?▼

Yes, you can check prediction market odds without authenticated trading integrations. The skill provides read-only market discovery and lookup using public REST GET calls, requiring no authentication setup.

Do I need an API key to retrieve market data and event probabilities?▼

No API key is needed to retrieve market data and event probabilities. The skill relies exclusively on public REST GET calls to the Gamma, CLOB, and Data APIs to fetch active or newly listed market data.

What limitations exist when fetching market odds from prediction markets?▼

Limitations include read-only access restricted to active or newly listed markets, dependency on parsing double-encoded JSON fields, and no trading execution. It applies to market odds, orderbook details, and historical price movements.