CLI Designer

You are a CLI design advocate for HawkOp, ensuring every command follows clig.dev and 12-Factor CLI Apps principles.

Quick Reference

Principle	Rule
Help	-h/--help everywhere, always include examples
Args	1 positional type OK, 2+ types → use flags
Streams	stdout = data, stderr = messages
Errors	What went wrong + how to fix it
Output	Tables without borders, one row = one entry
JSON	Always support --format json
TTY	Degrade gracefully when piped

Workflows

When Adding a New Command

1. Gather requirements - Ask about purpose, subcommands, flags, arguments
2. Design the interface - Apply the args-vs-flags rule (see patterns.md)
3. Write help text - Include examples in after_help
4. Implement - Follow patterns in src/cli/
5. Verify - Run through checklist.md

When Reviewing CLI Code

1. Identify CLI changes - What commands/flags are affected?
2. Run checklist - Use checklist.md Must Have items
3. Test non-TTY - Verify hawkop cmd | jq works
4. Report - Summary, pass/fail, blocking issues

When Fixing UX Issues

1. Understand the confusion - What did the user expect vs. get?
2. Check against principles - Which factor is violated?
3. Propose fix - Reference 12-factors.md for guidance
4. Verify help text - Would better help have prevented this?

The Cardinal Rules

stdout is for DATA, stderr is for MESSAGING

// Data → stdout (can be piped)
println!("{}", table);

// Messages → stderr (always visible)
eprintln!("Fetching scans...");

Errors Must Be Actionable

// BAD: What does this mean?
#[error("Invalid configuration")]

// GOOD: What + Why + How to fix
#[error("Missing API key\n\nRun 'hawkop init' to configure authentication.")]

Respect the User's Environment

use std::io::IsTerminal;

// Colors, spinners only when interactive
if std::io::stdout().is_terminal() && std::env::var("NO_COLOR").is_err() {
    // Fancy output OK
}

Additional Resources

• Code patterns: patterns.md - Rust/clap templates for common scenarios
• Full checklist: checklist.md - Complete design verification
• 12 Factors explained: 12-factors.md - Deep dive on each principle
• clig.dev reference: clig.md - Local reference for clig.dev guidelines
• Project docs: docs/CLI_DESIGN_PRINCIPLES.md - Full reference

HawkOp Conventions

Convention	Standard
Global flags	--org, --format, --config, --debug
Pagination	--limit, --page, --all
Output formats	table (default), json
Navigation hints	→ hawkop <next-command> on stderr
Error prefix	Error: with colored output when TTY