The @storybook/core package is the core of Storybook. It is responsible for the following:

• the main UI of storybook
• the UI used by addons
• the API used by addons
• the API used by the CLI
• the API used by the server
• prebundled code used by the browser
• static assets used by the browser
• utilities for CSF, MDX & Docs

This package is not intended to be used by anyone but storybook internally.

Even though this is where all of the code is located, it is NOT to be the entry point when using functionality within!

Consumers of the code should import like so:

import { addons } from 'storybook/manager-api';

Importing from @storybook/core is explicitly NOT supported; it WILL break in a future version of storybook, very likely in a non-major version bump.

In the following packages you should import from @storybook/core (and ONLY from @storybook/core):

• @storybook/core
• @storybook/codemod

To prevent cyclical dependencies, these packages cannot depend on the storybook package.

In every other package you should import from storybook/internal (and ONLY from storybook/internal).

The heuristic is simple:

If you see a peerDependency on storybook in the package.json of the package you are working on, you should import from storybook/internal.

The sole exception is the storybook package itself.

Obviously, the storybook package cannot depend on itself, so it must import from @storybook/core.