What does thinking mode do?

It lets the AI plan its reply before writing it, which usually makes the answer more thoughtful and consistent. Expand the Thoughts panel above a reply to read that planning. Thinking costs a few extra credits on most models — the price is shown when you turn it on, and you are only charged when thinking actually happened. Some models do not offer it at all: a few accept the request and then never produce any thinking, so it is switched off for them rather than left there doing nothing.