> Using Plan mode in Cline or other agent based workflows is day and night in the outputs.

Agreed. My tool agnostic workflow is to work up a planning/spec doc in the docs/feature-plans folder. I use one chat thread to make that. First it creates the basic plan, then then we pick it apart together, I manually fix bad assumptions, then in a new chat, we implement.

Before and after implementation, I run my /gilfoyle command for a constructive roast, then my /sec command for a thorough security review. After implementing this, and a bit more, the final LLM output quality is much higher.

edit: adding "make sure we are applying known patterns used in our app for our solution, don't reinvent the wheel." helped a ton. I am on mobile atm, and that might not be the exact wording.

When it tells me that I need to switch to act mode for it to read files and create a detailed the plan, I just chide gently and ask it to read the damn files in plan mode. Works every time. I wish I dont have to do that.

Cline plan mode doesn't tend to read files by default but you can tell it 'read all files necessary to establish a detailed plan'. GPT5 also seems more eager to read files.

You can just add the files to the prompt with the @ sign.