cli-developer

Build cross-platform CLI tools with argument parsing, interactive prompts, and shell completions. Load detailed guidance based on context: For Python (click/typer) and Go (cobra) quick-start examples, see references/python-cli.md and references/go-cli.md . When implementing CLI features, provide: CLI frameworks (commander, yargs, oclif, click, typer, argparse, cobra, viper), terminal UI (chalk, inquirer, rich, bubbletea), testing (snapshot testing, E2E), distribution (npm, pip, homebrew, releases), performance optimization Documentation - Covers Node.js (commander, yargs), Python (click, typer), and Go (cobra, viper) frameworks with design patterns for subcommands, flags, and configuration - Includes UX patterns for progress bars, spinners, color output with TTY detection, and graceful signal handling - Requires startup time under 50ms, consistent flag naming, non-interactive fallbacks for CI/CD, and shell completion generation - Enforces cross-platform testing (Windows, macOS, Linux) and proper stderr/stdout separation for piped output - Analyze UX — Identify user workflows, command hierarchy, common tasks. Validate by listing all commands and their expected --help output before writing code. - Design commands — Plan subcommands, flags, arguments, configuration. Confirm flag naming is consistent and no existing signatures are broken. - Implement — Build with the appropriate...