Before GUIs took off, there were more command-driven applications. The program would respond with text answers like a specialized chat. As I said yesterday, this is not a Language User Interface (LUI), which would use natural language, not specialized commands.

One benefit that command driven systems have over modern GUI systems is that ChatGPT could probably drive them. Large language models seem to have no problem learning programming languages, even niche ones. You can even teach them new ones in your prompt.

To take advantage of this, we should be adding very well specified mini-languages to our applications to help our users get help from ChatGPT. Here’s a simple example based on a fictional airline flights query language I made up:

In your application, you would offer a command window that already has primed ChatGPT with the specification of the language and many examples. I barely had to do anything to get it learn this simple command. I went on in the chat to ask for more complicated queries, even a series of queries to find out about connecting flights, and it had no problems.

In your application, you only need to parse the terminal like commands, which is a lot easier than implementing a natural language parser, even for a constrained topic like airline booking.

I’m sure ChatGPT could build the command parser for you too if you wanted.