npm command-line interface

# npm-explain

Explain installed packages

## Table of contents

- Synopsis
- Description
- Configuration

- `json`
- `workspace`

- See Also

### Synopsis

    npm explain <package-spec>

    alias: why

### Description

This command will print the chain of dependencies causing a given package to be installed in the current project.

If one or more package specs are provided, then only packages matching one of the specifiers will have their relationships explained.

The package spec can also refer to a folder within `./node_modules`

For example, running `npm explain glob` within npm's source tree will show:

    glob@7.1.6
    node_modules/glob
      glob@"^7.1.4" from the root project

    glob@7.1.1 dev
    node_modules/tacks/node_modules/glob
      glob@"^7.0.5" from rimraf@2.6.2
      node_modules/tacks/node_modules/rimraf
        rimraf@"^2.6.2" from tacks@1.3.0
        node_modules/tacks
          dev tacks@"^1.3.0" from the root project

To explain just the package residing at a specific folder, pass that as the argument to the command. This can be useful when trying to figure out exactly why a given dependency is being duplicated to satisfy conflicting version requirements within the project.

    $ npm explain node_modules/nyc/node_modules/find-up
    find-up@3.0.0 dev
    node_modules/nyc/node_modules/find-up
      find-up@"^3.0.0" from nyc@14.1.1
      node_modules/nyc
        nyc@"^14.1.1" from tap@14.10.8
        node_modules/tap
          dev tap@"^14.10.8" from the root project

### Configuration

#### `json`

- Default: false
- Type: Boolean

Whether or not to output JSON data, rather than the normal output.

- In `npm pkg set` it enables parsing set values with JSON.parse() before saving them to your `package.json`.

Not supported by all npm commands.

#### `workspace`

- Default:
- Type: String (can be set multiple times)

Enable running a command in the context of the configured workspaces of the current project while filtering by running only the workspaces defined by this configuration option.

Valid values for the `workspace` config are either:

- Workspace names
- Path to a workspace directory
- Path to a parent workspace directory (will result in selecting all workspaces within that folder)

When set for the `npm init` command, this may be set to the folder of a workspace which does not yet exist, to create the folder and set it up as a brand new workspace within the project.

This value is not exported to the environment for child processes.

### See Also

- package spec
- npm config
- npmrc
- npm folders
- npm ls
- npm install
- npm link
- npm prune
- npm outdated
- npm update