CLI Design Considerations

"Traditionally, UNIX commands were written under the assumption they were going to be used primarily by other programs. They had more in common with functions in a programming language than with graphical applications." "Today, even though many CLI programs are used primarily (or even exclusively) by humans, a lot of their interaction design still carries the baggage of the past. It’s time to shed some of this baggage: if a command is going to be used primarily by humans, it should be designed for humans first."

https://clig.dev

• Standard in/out/err
• Signals
• Exit codes
• Use of config (e.g. YAML, JSON, etc)
• Anticipant users not using it as you anticipated
• Designing for composability
• Output verbosity
• Whether to use a "top", such as HTop

Guides

• CLI Guidelines

Conventions

> mycli --descriptive
> mycli -d

Subcommand Choices

• netlify functions:invoke
• netlify functions invoke

Concept of a TUI

TUI stands for Terminal User Interface and basically describes an app that runs in the terminal (in the same manner as a CLI-based application) that has a more interactive user interface.

Examples

• https://github.com/oz/tz
• https://github.com/charmbracelet/soft-serve

Things to consider for a TUI...

• Autocompletion (e.g. https://github.com/chriswalz/bit)
• Color and visual representation

Libraries

• Inquirer
• Chalk
• Charm
• React Ink - React for interactive command-line apps
• Cobra - ...library for creating powerful modern CLI applications
• blessed - curses-like library with a high level terminal interface API for node.js
• nice - highly customizable and lightweight framework for crafting CLI apps
• laterna - Java library allowing you to write easy semi-graphical user interfaces

Great CLIs

• CLI tools you won't be able to live without
• git
• kubectl
• brew

Completion

• Creating a bash completion script