Kitson Market Replay Paper-Trading Coach: Practise Decisions With the Future Hidden (Opus 5.5)

Practise trading decisions bar by bar with the future hidden, on paper money, then see how you decided against your own plan.

Add your own historical price file (CSV: date, open, high, low, close) or use the made-up sample. The market is always shown under a made-up name, and the dates are hidden. Write your plan first: risk per trade, the least reward-to-risk you accept, the most trades, when you stop after losses in a row, the direction and your rule for moving stops.

Then press "Start the replay". The app shows some history, then one bar at a time, and never a bar after the one you have reached. Place paper trades (size, stop, target), move a stop or a target, close, or pass, with a short note for each decision.

Market Replay Paper-Trading Coach then scores the session in code on your own computer:

- every order fills at the open of the next bar, with your slippage and commission; stops, targets and gaps are handled bar by bar;

- each trade's result after costs and in R, the paper balance and its largest fall;

- every decision checked against your written plan: risk, stops, targets, the most trades, losses in a row, direction and moved stops;

- your plan run again exactly as first written on the same bars, to set beside what you did;

- patterns in your decisions: how long you took, entries soon after a pass, stops moved, hand closes and quick re-entries after a loss.

Claude Opus 5.5 then coaches your decision process from those figures and your notes, takes up every departure from your plan and asks you questions to reflect on.

What makes it different

- The future stays hidden. Only the bars up to the one you have reached are ever read, scored or drawn, and fills come at the next bar's open, so nothing is decided with hindsight.

- Your process, not the market. It never says a trade was good or bad, never says where the market was going, and never says what to trade. If the coaching drifts into advice, verdicts, forecasts or promises, the app catches it and asks for a rewrite.

- Every number in the coaching is checked in code against the app's own figures, and the result of that check is shown to you.

- Your price file stays on your computer. Its dates are never shown or sent. Anthropic is sent the app's own figures, your decisions with your notes, and your plan, and you can see exactly what will be sent before anything goes.

- The cost is shown before every run, and you set a limit. In our own test on the made-up sample session, a run cost about 10 cents on our own Anthropic account, and one change about 7 cents more. The replay itself is free.

- A Word report and an Excel file of the trades, every decision with its note, the departures from your plan, the patterns and the plan version, with a chart of the session as you saw it.

What you need

- Free Node.js 18+ (Windows, Mac or Linux).

- Your own Anthropic account and API key, with a little credit. A Claude chat subscription does not include API access.

- Your own historical price file (date, open, high, low, close), or use the made-up sample in the zip.

You pay Anthropic directly for what you use, on top of the price of the app.

Educational only. Paper trading on a replay of historical or made-up prices. No real money. Past or simulated results do not predict future results. Not financial advice. It scores your decisions against your own plan and does not recommend any trade. Fills at the next bar's open are a model, and real fills can be worse. The app never places trades. Trading involves risk of loss. If we can't get the app running for you, email kit376351@gmail.com within 14 days for a refund of the app price. Kitson Workshop is not affiliated with or endorsed by Anthropic.