cli-ux-patterns

Error messages should follow a 3-part pattern: clearly state what went wrong, explain why it happened, and guide users on how to fix it. This approach makes errors actionable rather than cryptic, reducing user frustration and support overhead.

Use semantic colors that map status to meaning—green for success, red for error, yellow for warnings. Always respect the NO_COLOR environment variable so users who need plain output or use screen readers aren't forced into colored text.

Progress bars and spinners signal to users that work is happening. Use spinners for indeterminate tasks and progress bars when you know the total steps. Libraries like indicatif handle formatting and performance so you don't block output.

Prompt only when the decision is critical and the user is present; otherwise fail loudly with actionable guidance or apply smart defaults. Interactive prompts should be safe—validate input and offer sensible defaults to reduce user burden.

Provide dual output modes: human-readable text for direct terminal use and structured formats like JSON for programmatic consumption. This lets scripts reliably extract data while keeping the CLI approachable for manual use.

Yes. Error messages, color handling, progress indicators, and output formatting patterns work across any CLI—Rust, Python, Go, or others. The principles are platform-agnostic; implementation uses language-specific libraries like miette or owo-colors.