In the previous chapters, we discussed the design of AI agents and models, as well as the potential of employing AI agents for various scales of collaboration and interaction. As mentioned in Sect.  1.3 , AI models should not be dismissed in the LLM era; instead, consideration should be given to achieving synergy through multi-scale model interaction. To this end, this chapter begins with the traditional concept of data augmentation applied to novel tasks within financial scenarios in Sect. 5.1, followed by a discussion on the dynamic interaction loop between large and small language models in Sect. 5.2. Finally, we conclude by emphasizing the importance of multi-scale model synergy in Sect. 5.3.