How to Vet a Trading Robot Before Buying

Vetting someone else's robot comes down to one question: what does it do with a losing position? The answer determines everything else, and you can obtain it without the source code.

Signs of a hidden martingale or grid

Look for these before anything else. A win rate near one hundred percent. No large losing trades despite a long history. A rising average position size. A large number of simultaneously open trades. A drawdown absent from the closed-trade chart but present on the equity chart. Any one of these means losing positions are not being closed but accumulated.

Read the equity curve, not the balance curve

This is the key practical technique. The balance curve counts only closed trades and looks perfect for grid robots. The equity curve includes open positions, and the real drawdown is visible only there. The divergence between the two curves is precisely what is being hidden from you.

Test it yourself, on your own conditions

Someone else's report was produced on someone else's account with someone else's spread. A run at your own broker with real costs often gives a different result — sometimes the opposite. It is also worth running the robot over a period other than the one the vendor shows: a shop window matching one favourable stretch occurs more often than chance would suggest.

Three questions for the vendor

What was the maximum floating drawdown over the entire history? What was the maximum number of simultaneously open positions? What does the robot do after five consecutive losses? The answers either close the subject or settle it — and a refusal to answer is itself an answer.

This material is educational and is not individual investment advice. Trading forex carries the risk of losing capital.