CLI Tool Design

Build command-line tools that are discoverable, composable, and pleasant to use.

Design Principles

The UNIX Philosophy Applied

1. Do one thing well — Each command has a clear, singular purpose
2. Compose through pipes — Support stdin/stdout for chaining
3. Fail loudly — Non-zero exit codes and stderr for errors
4. Be predictable — Consistent flags, consistent output format

Command Structure

program [global-options] command [command-options] [arguments]