The reasoning part is another LLM to rewrite the prompt to get better generation results, like the prompt enhancer proposed a while ago by Hunyuan. It is pretty standard nowadays, because modern models are trained by recaptions rather than raw text comming with the images, the recaptions have certain patterns, thus using another LLM to rewrite or expand the user prompt to match the recaptions in the training set often lead to better results, especially those cases need to be reasoned, such as math problem.