1. A design tool for designing a system, comprising: a display device displaying a user interface including a first visualization pane showing a symbolic representation of a first connection between a first port of a first element of the system and a second port of a second element of the system as a first port symbol, a second port symbol, and a connector symbol; a second visualization pane showing a first unconnected port of the first element of the system as a third port symbol; and a text entry pane showing a textual definition of the first connection.