pantheon-ai/commanderjs

Complete Commander.js CLI framework guidance covering command structure, options, arguments, subcommands, action handlers, version management, and TypeScript integration. Use when: building CLI tools, parsing command-line arguments, implementing subcommands, handling options/flags, creating interactive CLIs, or migrating from other CLI frameworks. Keywords: Commander.js, CLI, command-line, arguments, options, flags, subcommands, action handlers, version, help text, TypeScript, yargs, meow, program, parseAsync, opts, args, variadic, required options, default values, custom help, error handling

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99%

Review — 99%

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Commands & Subcommands

Name: pantheon-ai/commanderjs
Author: pantheon-ai

Complete guide to structuring commands and subcommands in Commander.js.

CRITICAL: Typed Options Pattern

Always pass options as typed objects to downstream services/modules.

Bad: Destructuring in Action

program
  .command('build')
  .option('-e, --env <name>', 'Environment')
  .action(({ env }) => {
    // ❌ BAD: Type information lost, unclear what's passed
    buildProject(env);
  });

Good: Typed Options Object

// types/build-options.ts
export interface BuildOptions {
  env: string;
  minify: boolean;
  outDir: string;
}

// services/build-service.ts
export const buildProject = (options: BuildOptions): void => {
  console.log('Building with:', options);
  // Service knows exactly what it receives
};

// commands/build.ts
import { Command } from 'commander';
import { buildProject } from '../services/build-service';
import type { BuildOptions } from '../types/build-options';

export const buildCommand = new Command('build')
  .description('Build the project')
  .option('-e, --env <name>', 'Environment', 'development')
  .option('-m, --minify', 'Minify output', false)
  .option('-o, --out-dir <path>', 'Output directory', './dist')
  .action((options: BuildOptions) => {
    // ✅ GOOD: Full typed object passed to service
    buildProject(options);
  });

Why Typed Options?

Type Safety: Compiler catches missing/incorrect options
Clarity: Service signature shows all required inputs
Testability: Easy to mock complete option objects
Maintainability: Add options without changing signatures
Documentation: Types document expected inputs

Basic Command

program
  .command('build')
  .description('Build the project')
  .action(() => {
    console.log('Building...');
  });

Multiple Commands

program
  .command('init')
  .description('Initialize project')
  .action(() => {
    console.log('Initializing...');
  });

program
  .command('build')
  .description('Build project')
  .action(() => {
    console.log('Building...');
  });

program
  .command('deploy')
  .description('Deploy project')
  .action(() => {
    console.log('Deploying...');
  });

await program.parseAsync(process.argv);

Command with Arguments

program
  .command('deploy')
  .description('Deploy to environment')
  .argument('<environment>', 'Target environment')
  .action((environment) => {
    console.log('Deploying to:', environment);
  });

// Usage: my-cli deploy production

Multiple Arguments

program
  .command('copy')
  .description('Copy files')
  .argument('<source>', 'Source file')
  .argument('<destination>', 'Destination file')
  .action((source, destination) => {
    console.log(`Copying ${source} to ${destination}`);
  });

// Usage: my-cli copy src.txt dst.txt

Optional Arguments

program
  .command('log')
  .description('Show logs')
  .argument('[lines]', 'Number of lines', '10')
  .action((lines) => {
    console.log(`Showing ${lines} lines`);
  });

// Usage: my-cli log
// or:    my-cli log 50

Variadic Arguments

program
  .command('add')
  .description('Add files')
  .argument('<files...>', 'Files to add')
  .action((files) => {
    console.log('Adding files:', files);
  });

// Usage: my-cli add file1.js file2.js file3.js

Command with Options

program
  .command('build')
  .description('Build project')
  .option('-e, --env <name>', 'Environment', 'development')
  .option('-w, --watch', 'Watch mode')
  .option('-m, --minify', 'Minify output')
  .action((options) => {
    console.log('Building with options:', options);
  });

// Usage: my-cli build --env production --minify

Modular Commands (Recommended Pattern)

Create subcommands as exported Command instances, with typed options passed to services:

Full Stack: Types → Service → Command

// types/build-options.ts
export interface BuildOptions {
  env: string;
  minify: boolean;
  outDir: string;
}

// services/build-service.ts
import type { BuildOptions } from '../types/build-options';

export const buildProject = (options: BuildOptions): void => {
  console.log('Building with:', options);
  // Implementation receives fully typed options
};

// commands/build.ts
import { Command } from 'commander';
import { buildProject } from '../services/build-service';
import type { BuildOptions } from '../types/build-options';

export const buildCommand = new Command('build')
  .description('Build project')
  .option('-e, --env <name>', 'Environment', 'development')
  .option('-m, --minify', 'Minify output', false)
  .option('-o, --out-dir <path>', 'Output directory', './dist')
  .action((options: BuildOptions) => {
    // Pass complete typed options object to service
    buildProject(options);
  });

// types/deploy-options.ts
export interface DeployOptions {
  branch: string;
  force: boolean;
}

// services/deploy-service.ts
import type { DeployOptions } from '../types/deploy-options';

export const deployApp = (environment: string, options: DeployOptions): void => {
  console.log(`Deploying ${options.branch} to ${environment}`);
  // Service receives environment + typed options
};

// commands/deploy.ts
import { Command } from 'commander';
import { deployApp } from '../services/deploy-service';
import type { DeployOptions } from '../types/deploy-options';

export const deployCommand = new Command('deploy')
  .description('Deploy application')
  .argument('<environment>', 'Target environment')
  .option('-b, --branch <name>', 'Branch', 'main')
  .option('-f, --force', 'Force deployment', false)
  .action((environment: string, options: DeployOptions) => {
    // Pass all arguments + typed options to service
    deployApp(environment, options);
  });

// index.ts
import { Command } from 'commander';
import { buildCommand } from './commands/build';
import { deployCommand } from './commands/deploy';

const program = new Command();

program
  .name('my-cli')
  .version('1.0.0')
  .addCommand(buildCommand)
  .addCommand(deployCommand);

await program.parseAsync(process.argv);

Directory Structure with Service Layer

src/
├── types/
│   ├── build-options.ts      # BuildOptions interface
│   ├── deploy-options.ts     # DeployOptions interface
│   └── index.ts              # Barrel exports
├── services/
│   ├── build-service.ts      # buildProject(options: BuildOptions)
│   ├── deploy-service.ts     # deployApp(env, options: DeployOptions)
│   └── index.ts              # Barrel exports
├── commands/
│   ├── build.ts              # Export buildCommand
│   ├── deploy.ts             # Export deployCommand
│   └── index.ts              # Barrel exports
└── index.ts                  # Main program

Barrel Exports for Commands

// commands/index.ts
export { buildCommand } from './build';
export { deployCommand } from './deploy';
export { testCommand } from './test';

// index.ts
import { Command } from 'commander';
import { buildCommand, deployCommand, testCommand } from './commands';

const program = new Command();

program
  .name('my-cli')
  .version('1.0.0')
  .addCommand(buildCommand)
  .addCommand(deployCommand)
  .addCommand(testCommand);

await program.parseAsync(process.argv);

Subcommands with Modular Pattern + Typed Options

Subcommands follow the same pattern: types → services → commands:

// types/migrate-options.ts
export interface MigrateOptions {
  rollback: boolean;
  steps?: number;
}

// types/seed-options.ts
export interface SeedOptions {
  clear: boolean;
}

// services/database-service.ts
import type { MigrateOptions } from '../types/migrate-options';
import type { SeedOptions } from '../types/seed-options';

export const runMigrations = (options: MigrateOptions): void => {
  if (options.rollback) {
    console.log('Rolling back migration');
  } else {
    console.log('Running migrations');
  }
};

export const seedDatabase = (env: string, options: SeedOptions): void => {
  console.log('Seeding database for:', env);
  if (options.clear) {
    console.log('Clearing existing data first');
  }
};

// commands/db/migrate.ts
import { Command } from 'commander';
import { runMigrations } from '../../services/database-service';
import type { MigrateOptions } from '../../types/migrate-options';

export const migrateCommand = new Command('migrate')
  .description('Run database migrations')
  .option('--rollback', 'Rollback last migration', false)
  .option('--steps <number>', 'Number of migrations')
  .action((options: MigrateOptions) => {
    runMigrations(options);
  });

// commands/db/seed.ts
import { Command } from 'commander';
import { seedDatabase } from '../../services/database-service';
import type { SeedOptions } from '../../types/seed-options';

export const seedCommand = new Command('seed')
  .description('Seed database')
  .argument('[env]', 'Environment', 'development')
  .option('--clear', 'Clear existing data', false)
  .action((env: string, options: SeedOptions) => {
    seedDatabase(env, options);
  });

// commands/db/index.ts
import { Command } from 'commander';
import { migrateCommand } from './migrate';
import { seedCommand } from './seed';

export const dbCommand = new Command('db')
  .description('Database operations')
  .addCommand(migrateCommand)
  .addCommand(seedCommand);

// index.ts
import { Command } from 'commander';
import { dbCommand } from './commands/db';

const program = new Command();

program
  .name('my-cli')
  .version('1.0.0')
  .addCommand(dbCommand);

await program.parseAsync(process.argv);

// Usage: my-cli db migrate --rollback
//        my-cli db seed production --clear

Inline Subcommands (Less Maintainable)

const db = program.command('db');
db.description('Database commands');

db.command('migrate')
  .description('Run migrations')
  .action(() => {
    console.log('Running migrations...');
  });

db.command('seed')
  .description('Seed database')
  .action(() => {
    console.log('Seeding database...');
  });

// Usage: my-cli db migrate
//        my-cli db seed

Nested Subcommands

// commands/docker/container/start.ts
import { Command } from 'commander';

export const startCommand = new Command('start')
  .description('Start container')
  .argument('<name>', 'Container name')
  .action((name) => {
    console.log('Starting container:', name);
  });

// commands/docker/container/stop.ts
import { Command } from 'commander';

export const stopCommand = new Command('stop')
  .description('Stop container')
  .argument('<name>', 'Container name')
  .action((name) => {
    console.log('Stopping container:', name);
  });

// commands/docker/container/index.ts
import { Command } from 'commander';
import { startCommand } from './start';
import { stopCommand } from './stop';

export const containerCommand = new Command('container')
  .description('Container operations')
  .addCommand(startCommand)
  .addCommand(stopCommand);

// commands/docker/index.ts
import { Command } from 'commander';
import { containerCommand } from './container';

export const dockerCommand = new Command('docker')
  .description('Docker operations')
  .addCommand(containerCommand);

// index.ts
import { Command } from 'commander';
import { dockerCommand } from './commands/docker';

const program = new Command();

program
  .name('my-cli')
  .version('1.0.0')
  .addCommand(dockerCommand);

await program.parseAsync(process.argv);

// Usage: my-cli docker container start my-app
//        my-cli docker container stop my-app

Command Aliases

export const installCommand = new Command('install')
  .alias('i')
  .description('Install dependencies')
  .action(() => {
    console.log('Installing...');
  });

// Usage: my-cli install
// or:    my-cli i

Default Command

export const serveCommand = new Command('serve')
  .description('Start server')
  .action(() => {
    console.log('Starting server...');
  });

program.addCommand(serveCommand, { isDefault: true });

// Usage: my-cli
// (runs serve command by default)

Hidden Commands

export const debugCommand = new Command('debug')
  .description('Debug mode')
  .hideCommand()
  .action(() => {
    console.log('Debug mode enabled');
  });

// Hidden from help text

Command-Specific Help

export const deployCommand = new Command('deploy')
  .description('Deploy application')
  .argument('<environment>', 'Target environment')
  .option('-d, --dry-run', 'Dry run')
  .addHelpText('after', `
Examples:
  $ my-cli deploy production
  $ my-cli deploy staging --dry-run
  `);

TypeScript Command Factory Pattern

// commands/build.ts
import { Command } from 'commander';

interface BuildOptions {
  env: string;
  minify: boolean;
  watch: boolean;
}

export const buildCommand = new Command('build')
  .description('Build project')
  .option('-e, --env <name>', 'Environment', 'development')
  .option('-m, --minify', 'Minify output', false)
  .option('-w, --watch', 'Watch mode', false)
  .action((options: BuildOptions) => {
    console.log('Building with options:', options);
  });

Complete Modular Example

// commands/build.ts
import { Command } from 'commander';

export const buildCommand = new Command('build')
  .description('Build project')
  .option('-e, --env <name>', 'Environment', 'development')
  .option('-w, --watch', 'Watch mode')
  .action((options) => {
    console.log('Building for:', options.env);
  });

// commands/deploy.ts
import { Command } from 'commander';

export const deployCommand = new Command('deploy')
  .description('Deploy application')
  .argument('<environment>', 'Target environment')
  .option('-b, --branch <name>', 'Git branch', 'main')
  .option('-d, --dry-run', 'Dry run')
  .action((environment, options) => {
    console.log(`Deploying ${options.branch} to ${environment}`);
    if (options.dryRun) {
      console.log('Dry run - no changes made');
    }
  });

// commands/db/migrate.ts
import { Command } from 'commander';

export const migrateCommand = new Command('migrate')
  .description('Run migrations')
  .option('--rollback', 'Rollback last migration')
  .action((options) => {
    if (options.rollback) {
      console.log('Rolling back migration');
    } else {
      console.log('Running migrations');
    }
  });

// commands/db/seed.ts
import { Command } from 'commander';

export const seedCommand = new Command('seed')
  .description('Seed database')
  .argument('[env]', 'Environment', 'development')
  .action((env) => {
    console.log('Seeding database for:', env);
  });

// commands/db/index.ts
import { Command } from 'commander';
import { migrateCommand } from './migrate';
import { seedCommand } from './seed';

export const dbCommand = new Command('db')
  .description('Database operations')
  .addCommand(migrateCommand)
  .addCommand(seedCommand);

// commands/index.ts
export { buildCommand } from './build';
export { deployCommand } from './deploy';
export { dbCommand } from './db';

// index.ts
import { Command } from 'commander';
import { buildCommand, deployCommand, dbCommand } from './commands';

const program = new Command();

program
  .name('project-cli')
  .description('Project management CLI')
  .version('1.0.0')
  .addCommand(buildCommand)
  .addCommand(deployCommand)
  .addCommand(dbCommand);

await program.parseAsync(process.argv);

Directory Structure

src/
├── commands/
│   ├── build.ts          # buildCommand export
│   ├── deploy.ts         # deployCommand export
│   ├── db/
│   │   ├── migrate.ts    # migrateCommand export
│   │   ├── seed.ts       # seedCommand export
│   │   └── index.ts      # dbCommand export
│   └── index.ts          # Barrel exports all commands
└── index.ts              # Main program + addCommand()

Best Practices

Export Command instances from subcommand modules
Use .addCommand() to attach to parent Command
Create barrel exports in commands/index.ts
One command per file (following single function per module pattern)
Use descriptive command names that clearly indicate action
Group related commands in subdirectories
Provide clear descriptions for all commands
Use TypeScript interfaces for typed options
Document examples in help text for complex commands
Validate arguments in action handlers

Why Modular Commands?

Testability: Each command can be tested in isolation
Maintainability: Easy to find and modify specific commands
Reusability: Commands can be reused across different CLIs
Separation of concerns: Business logic separated from CLI structure
Barrel exports: Clean import statements in main program
Type safety: Better TypeScript inference with exported types

Install with Tessl CLI

npx tessl i pantheon-ai/commanderjs@0.1.0

references

actions-handlers.md

commands-structure.md

core-basics.md

options-flags.md

practices-patterns.md

typescript-setup.md

SKILL.md

tile.json