I've been experimenting quite a bit with long-horizion agentic coding[1] and I have also noticed that agents seem to perform worse when forced into certain architectural patterns. I have found that is a bit better when including the constraints along the way instead of adding them after the fact. There seems to be a side-effect I have been calling "calcification", where a pattern starts appearing in the codebase and the agent follows the pattern to the point where it dominates the context and becomes self-reinforcing. This could potentially be a strength or a weakness for existing code bases depending the codebase quality. I will have more insights on this soon as more from-scratch runs conclude that include architectural guidance from the beginning.
[1]: https://medium.com/@vishvananda/i-spent-2-billion-tokens-wri...
> agents seem to perform worse when forced into certain architectural patterns.
FWIW I've noticed this too. I've found that the agents/models have their own style, which is mostly summed up as overly verbose.
Additionally, the models are OK at modularization when given space to "plan" their implementation, but rarely decide that abstracting something would be helpful after the fact (i.e. after many iterations on a greenfield codebase or when being dropped into a legacy codebase).
This often leads to "god files" which, when pointed to by the user/architect, causes the models to correctly critique (humorously when they're the ones that wrote the code in the first place).