CLI Development Guidelines

Best practices for designing and implementing command-line interface (CLI) applications across programming languages.

CLI Design Principles

Unix Philosophy

Follow the core Unix philosophy for robust, composable CLIs:

• Do one thing well - Each command should have a single, well-defined responsibility
• Make it composable - Design output to work as input to other programs
• Handle text streams - CLIs work with stdin/stdout/stderr
• Exit cleanly - Use appropriate exit codes (0 for success, non-zero for errors)
• Fail fast - Detect and report problems immediately
• Be scriptable - All functionality must be accessible from non-interactive contexts

Command Structure