I don't think demo-magic is going to be best tool for interactive demos.
I suspect we want something we write ourselves that supports readline. 1. prints some instructions. 2. reads the command the user enters. Validates that command against the expected command. 3. prints a warning if the command is incorrect 4. runs the command 5. validates that the exit code is as expected. 6. asks the user for confirmation or if they want to run another command. 7. moves on.