Intelligent Books are Web-based textbooks that can adapt and improve their content and guide students through graphical example exercises that resemble the diagrams and notations a student might use on paper. The exercises use formal AI systems to analyse students' work, and different AI systems are used for different questions. This brings the issue of how a person can write questions if they are not an expert in the AI system used. We describe our experiences developing an authoring tool for electronics questions that use a specialised circuit AI with its own extensive circuit language. The tool works on the principle of exposing an appropriate visual model of the AI, while factoring out the language detail and the architecture of the book itself, and allowing the question writer to decide which parts of the AI model to expose to the student (as the desired mental model for the student).