How do I write my agent's prompt so it answers questions and still steers toward booking?

Add an instruction such as: always lead towards a goal. If you are asked a question, answer it and then redirect the user back to the goal, for example booking a demo or an appointment, or asking if they have any more questions.

Then check the rest of the prompt for conflicting instructions, which make the agent behave oddly, give strange answers or pause. For example, a line saying respond immediately with one short sentence, two at most, conflicts with a line saying answer questions fully or lead the conversation. Make the instructions clear and consistent, for example: one question at a time, never pause, always answer questions, then lead to the goal.

If the agent's goal says it is role playing, it may not call its booking tool, because role play is its goal. Either tell it plainly that it is booking real appointments, or turn the booking tool off for a pure role play demo.