Prediction markets / AI systems

AI for prediction markets,
built as a system.

We build the harness around the model: data, calibration, edge detection, execution and risk. For Polymarket and other event markets.

See the harness
01Data
02Model
03Edge
04Execution
05Evaluation

01 / The failure

The model is not the strategy.

The demo works. The live account does not. The missing layer is the harness.

01

A forecast is not an edge

The market already prices the obvious. A model that agrees with the crowd has no trade, no matter how good the prose is.

02

A signal is not a trade

Fees, spread, liquidity and size decide whether the edge survives contact with the order book.

03

A backtest is not a system

Live feeds break, orders miss, calibration drifts. Someone has to watch the thing at 3 a.m.

Most teams start by plugging an LLM into an API key. That is the first week, not the product. The market does not care about your demo.

02 / The harness

Five layers the model does not write for you.

The model is a commodity. The system around it is the advantage.

01 / Data

Market feeds, order books, resolution rules, external data.

Snapshots you can replay, not a stream you hope to catch.

02 / Model

A probability, not a paragraph.

LLM, statistical or ensemble. One calibration layer turns confidence into a number.

03 / Edge

Model probability minus price, fees and fill cost.

Ranked opportunities, not a watchlist of everything.

04 / Execution

Sizing, limits, order types, cancellation, kill switch.

Paper before live. Human approval where the size justifies it.

05 / Evaluation

Backtests, live paper, traces, P&L attribution.

Calibration drift is a first-class metric, not an afterthought.

More on the thesis: the harness is the moat

03 / The work

Three ways to start.

You do not have to begin with live money. Most teams should not.

Research scanner

Find the gap before risking money.

Scans markets, reads resolution rules, builds a probability with evidence and ranks the gaps against the book. No orders, no exposure.

Market scanResolution rulesEvidenceRanking

Execution agent

The model proposes. The harness disposes.

Places orders inside explicit limits: size, price, liquidity, daily loss. Paper trading first, human approval and a kill switch.

SizingLimitsPaper tradingKill switch

Risk and monitoring

See the failure before the loss.

Exposure, calibration drift, failed orders and fee drag in one place. A short daily brief instead of another dashboard nobody opens.

ExposureCalibration driftFee dragDaily brief

04 / From production

What we learned building one.

A prediction market system we built and run. No client names, no P&L promises, just the parts that mattered.

Weather, priced against an ensemble

The edge was not the prompt. It was the data pipeline: an open weather ensemble, a calibrated mapping to the market question, and a filter for markets where the book was thin. The model was the easy part.

Lesson: the data pipeline carried the edge.

An LLM forecaster that was too confident

Raw model probabilities were overconfident at the tails. A calibration layer and a market filter made the output usable. The lesson: an uncalibrated forecast is a liability, not an edge.

Lesson: calibrate before you size.

Fees and liquidity ate the first strategy

The naive signal looked profitable until fees, spread and size were included. A fee-aware sizer and a liquidity filter turned it into something that could survive live.

Lesson: the book is part of the model.

05 / Beyond Polymarket

Event markets first. Then the rest.

Prediction markets are a good starting point: clean questions, fast feedback, public data. The same five layers apply to trading, hedging and arbitrage on other venues.

Trading

Signals, sizing and execution on liquid markets. The harness decides what reaches the book.

Hedging

You cannot hedge what you cannot measure. Limits, scenarios and a clear audit trail.

Arbitrage

Two prices, one position. Latency, fees and fill probability are the whole game.

06 / How we start

Diagnostic, prototype, production.

No live money on day one. The first deliverable is a decision, not a trade.

01

Diagnostic

1 to 2 weeks

We audit the data, the model and the execution path. You get a short report: what is missing, what to build first, what not to build.

02

Prototype

4 to 6 weeks

A scanner or a paper-trading agent on your data. No live money until the evaluation is clear and the failure modes are named.

03

Production

Ongoing

Live system, monitoring, calibration and a retainer. We stick around for the failure modes, not just the launch.

Start with a diagnostic

Bring us the market. We will build the harness.

Tell us what you are trying to trade and what you have already tried. We will answer with a point of view, not a sales deck.

alex@vegaforge.dev ↗

VegaForge / Prediction markets