Gut answer is No. Honestly, they are no experts, or they wouldn't need you, so them reading and interpreting your code is a patently ridiculous request. Howev

Gut answer is No. Honestly, they are no experts, or they wouldn't need you, so them reading and interpreting your code is a patently ridiculous request. However, there is a huge opportunity here, based on the fact this is new ground for you and them. If they are truly worrying about justifying later the decisions to be made, then you CAN agree to design a report based on whatever your engine is doing, that shows addditional useful data (i.e., not just the correct decision in each situation, but the likelihood of it being correct or expected return). Invent a middle-ground solution. Then make them agree TO PAY FOR THIS REPORT AS PART OF THE CONTRACT.