compared some models for feature planning

I am normally using Claude Code for developing my personal projects but wanted to know how it compares to some other models. First try was to plan a new feature for my budget planning software I use. It is written in go and I want: load tracking. The prompt was rough about what I want and a hint that we only plan to write a detailed issue description that could be implemented later. As tool I used opencode. I let the model write the result into a folder outside the project directory so that the next run won't cheat and simply read the previous spec.