yarnpkg/yarn · error · MessageError

missingAddDependencies

Error message

missingAddDependencies

What it means

Thrown by the `yarn add` entry point when no package arguments are supplied. The lang string is 'Missing list of packages to add to your project.' `add.js:308` checks `if (!args.length)` immediately after parsing argv, before any install logic runs, so it is a pure argument-validation failure.

Source

Thrown at src/cli/commands/add.js:308

export function hasWrapper(commander: Object): boolean {
  return true;
}

export function setFlags(commander: Object) {
  commander.description('Installs a package and any packages that it depends on.');
  commander.usage('add [packages ...] [flags]');
  commander.option('-W, --ignore-workspace-root-check', 'required to run yarn add inside a workspace root');
  commander.option('-D, --dev', 'save package to your `devDependencies`');
  commander.option('-P, --peer', 'save package to your `peerDependencies`');
  commander.option('-O, --optional', 'save package to your `optionalDependencies`');
  commander.option('-E, --exact', 'install exact version');
  commander.option('-T, --tilde', 'install most recent release with the same minor version');
  commander.option('-A, --audit', 'Run vulnerability audit on installed packages');
}

export async function run(config: Config, reporter: Reporter, flags: Object, args: Array<string>): Promise<void> {
  if (!args.length) {
    throw new MessageError(reporter.lang('missingAddDependencies'));
  }

  const lockfile = await Lockfile.fromDirectory(config.lockfileFolder, reporter);

  await wrapLifecycle(config, flags, async () => {
    const install = new Add(args, flags, config, reporter, lockfile);
    await install.init();
  });
}

View on GitHub (pinned to c2dda503f3)

Solutions

1. Supply at least one package specifier: `yarn add lodash@^4.17.0`.
2. If scripting, default the variable: `yarn add "${PKG:?PKG is required}"`.
3. When calling `run(...)` programmatically, assert `args.length >= 1` first.

Example fix

// before
await run(config, reporter, flags, []);  // throws

// after
await run(config, reporter, flags, ['lodash']);

function requireAddArgs(args: string[]): string[] {
  if (!Array.isArray(args) || args.length === 0) {
    throw new Error('yarn add requires at least one package specifier');
  }
  return args;
}
// const safeArgs = requireAddArgs(args); await run(config, reporter, flags, safeArgs);

function hasAddArgs(args: unknown): args is string[] {
  return Array.isArray(args) && args.length > 0;
}

When it happens

Trigger: Invoking `run(config, reporter, flags, args)` for the `add` command with an empty `args` array (e.g. `yarn add` with nothing after it).

Common situations: Typo such as `yarn add ` with a trailing space, a shell alias/script that forwards an empty variable (`yarn add $PKG` where `$PKG` is unset), or misuse of the programmatic API.

Related errors

• invalidPackageName
• execMissingCommand
• tooManyArguments
• tooFewArguments
• workspacesAddRootCheck

AI-assisted analysis of yarnpkg/yarn@c2dda503f3 (2026-08-13). Data as JSON: /api/errors/a81481db4dfbef2e. Report an issue: GitHub.