...It organizes dozens of recommendations around command-line experience, distribution, interoperability, accessibility, testing, errors, development, analytics, versioning, and security. The guide emphasizes POSIX conventions, helpful prompts, structured output, predictable configuration, meaningful exit codes, and clean separation of stdout and stderr. It also discusses dependency size, shell completion, containerization, debugging, and cross-platform behavior. Each recommendation explains why the practice matters and often links to practical tools or example projects. ...