prediction_markets

Prediction markets

Prediction markets (Kalshi, Polymarket) trade binary/event contracts that pay 1 unit if an outcome happens and 0 if it doesn't. The contract's price therefore is the market's probability: a contract trading at 0.62 means a 62% implied chance.

Read the resolution rules first

The single biggest mistake is comparing two markets that resolve differently. Before any comparison, read market_detail for the exact question, the settlement source, and the expiry. "Team X wins the title" and "Team X wins the final" are different contracts. If the book's market and the prediction market don't resolve on the same condition, say so and stop — the comparison is invalid.

Price → probability

• Best bid / best ask (market_prices) bracket the fair value; use the mid for a point estimate and note the spread (wide spread = thin/uncertain market).
• Do not vig-remove a single binary contract price — it's already a probability. The exchange takes a fee on settlement, not a two-sided overround like a book.

The exchange-vs-book edge

This is the high-value play and why this agent exists:

1. Take the contract's implied probability (prediction market).
2. Take the SAME outcome at the sportsbooks (find_fixture → best_prices), and vig_removal the book market to a fair probability.
3. Compare. A meaningful gap means one side is mispriced relative to the other — report which side is the value, the size of the gap, and the venues. Liquidity and the fee/withdrawal frictions on each venue determine whether it's actually takeable.

Honesty

Surface the probabilities, the gap, and the caveats (thin liquidity, resolution-rule mismatch, fees). The user decides and acts; this agent never trades or bets.