Agent skill
commander
Use when building CLI tools with Commander.js - commands, options, arguments, and help text for Node.js command-line applications
Stars
163
Forks
31
Install this agent skill to your Project
npx add-skill https://github.com/majiayu000/claude-skill-registry/tree/main/skills/development/commander
SKILL.md
Commander.js CLI Framework
Quick Start
typescript
import { Command } from 'commander';
const program = new Command();
program
.name('mycli')
.version('1.0.0')
.description('My CLI tool');
program
.command('build <input>')
.description('Build the project')
.option('-o, --output <file>', 'Output file', 'output.json')
.option('-w, --watch', 'Watch mode')
.option('-v, --verbose', 'Verbose output')
.action((input, options) => {
console.log(`Building ${input} to ${options.output}`);
if (options.watch) startWatcher();
});
program.parse();
Command Patterns
| Pattern | Syntax | Description |
|---|---|---|
| Required arg | <name> |
Must be provided |
| Optional arg | [name] |
Can be omitted |
| Variadic | <files...> |
Multiple values |
| Option value | -o, --out <file> |
Option with value |
| Boolean flag | -v, --verbose |
True when present |
| Negatable | --no-cache |
Sets cache=false |
Subcommands
typescript
const build = program.command('build');
build
.command('dev')
.description('Development build')
.action(() => { /* ... */ });
build
.command('prod')
.description('Production build')
.action(() => { /* ... */ });
Key Features
typescript
// Default values
.option('-p, --port <number>', 'Port', '3000')
// Coercion
.option('-n, --number <n>', 'A number', parseInt)
// Required options
.requiredOption('-c, --config <path>', 'Config file')
// Choices
.option('-e, --env <env>', 'Environment').choices(['dev', 'prod'])
// Error handling
program.exitOverride(); // Throw instead of process.exit
program.configureOutput({ writeErr: (str) => logger.error(str) });
Tips
- Use
program.parse()at the end, orprogram.parseAsync()for async - Access args via action callback or
program.args - Use
.alias('b')for command shortcuts - Add examples with
.addHelpText('after', 'Examples:\n $ mycli build src/')
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