Some agent runtimes are still optimized for: run command -> wait -> parse output -> continue. That works for non-interactive tools, but breaks when a command needs stdin interaction (debuggers, installers, prompts, etc.).

contd starts the command in a managed background session and returns control when: - a timeout is reached, or - the process is waiting for stdin

I think it's useful for interactive TUIs or interactive install prompts.

In my repo, a demo video shows how an agent in Cursor which would get stuck when running interactive CLI can run gdb dynamically with the help of contd. (I know gdb can be executed in a non-interactive way by -q, but that's just showing the capability.)