I have a similar experience with GPT 5.6 sol.
Nowadays I often prompt like "I heard there is also this different direction, what do you think about that?"
Another thing I do is asking the agent to make a decision matrix for choices. It's useful to discuss, give feedback on, and signals that it's a discussion, not a request for a particular direction.
It's then also easy to say: create a prototype for multiple directions so I can compare the solutions.
That way I choose the problem, I choose the solution, but the agent can help me discover solutions, make tradeoffs visible, and implement solutions.