So I'd say claude 4 agents today are at smart but fresh intern level of autonomy. You still have to do the high level planning and task break down, but it can execute on tasks (say requiring 10 - 200 lines of code excluding tests). Any asking it to write much more code (200+ lines) often require a lot of follow ups and disappointment.
A significant portion of my prompts are writing and reading from .md files, which plan and document the progress.
When I start a new feature, it begins with: We need to add a new feature X that does ABC, create a .md in /docs to plan this feature. Ask me questions to help scope the feature.
I then manually edit the feature-x.md file, and only then tell the tool to implement it.
Also, after any major change, I say: Add this to docs/current_app_understanding.md.
Every single chat starts with: Read docs/current_app_understanding.md to get up to speed.
The really cool side benefit here is that I end up with solid docs, which I admittedly would have never created in the past.
You don't exactly need to know prompting, you just need to know how to ask the AI to help you prompt it.