Ask it to verify stuff in the browser. It can open a special Chrome instance, browse URLs, click and scroll around, inspect the DOM, and generally do whatever it takes to verify that the problem is actually solved, or it will go back and iterate more. That feedback loop IMO makes it very powerful for client-side or client-server development.

I've mentioned this before, but I think Gemini is the smartest raw model for answering programming questions in chatbot mode, but these CC/Codex/gemini-cli tools need more than just the model, the harness has to be architected intelligently and I think that's where Google is behind for the moment.