flins: Skill for Claude Code

Commander.js Guidelines

Overview

This skill provides guidance for building Node.js command-line interfaces using Commander.js. It covers common patterns for defining options, commands, arguments, and customizing the help system.

Quick Start

Installation

npm install commander

Basic Program

const { program } = require('commander');

program
  .option('-p, --port <number>', 'server port number')
  .option('-d, --debug', 'output extra debugging')
  .argument('<input>', 'input file to process')
  .action((input, options) => {
    console.log(`Processing ${input} on port ${options.port}`);
    if (options.debug) console.log('Debug mode enabled');
  });

program.parse();

Multi-Command Program

const { Command } = require('commander');
const program = new Command();

program
  .name('my-cli')
  .description('CLI tool for managing tasks')
  .version('1.0.0');

program.command('add')
  .description('Add a new task')
  .argument('<task>', 'task description')
  .action((task) => {
    console.log(`Added task: ${task}`);
  });

program.command('list')
  .description('List all tasks')
  .action(() => {
    console.log('Listing tasks...');
  });

program.parse();

Common Patterns

Options

Boolean Options

program.option('-d, --debug', 'enable debug mode');
// Usage: my-cli --debug

Value Options

program.option('-p, --port <number>', 'server port');
// Usage: my-cli --port 8080

Required Options

program.requiredOption('-k, --key <api-key>', 'API key is required');
// Usage: my-cli --key abc123

Variadic Options

program.option('-f, --files <files...>', 'files to process');
// Usage: my-cli --file file1.txt file2.txt file3.txt

Negatable Options

program.option('--no-cache', 'disable caching');
// Usage: my-cli --no-cache

Default Values

program.option('-p, --port <number>', 'server port', 3000);
// Default: 3000 if not specified