Thanks to its opiniated directory structure, Nuxt can auto-import your [`components/`](/docs/guide/directory-structure/components), [`composables/`](/docs/guide/directory-structure/components) and [`utils/`](/docs/guide/directory-structure/components).
Contrary to a classic global declaration, Nuxt preserves typings, IDEs completions and hints, and **only includes what is used in your production code**.
In the docs, every function that is not explicitly imported is auto-imported by Nuxt and can be used as-is in your code. You can find a reference for auto-imported components, composables and utilities in the [API section](/docs/api).
You can also auto-import functions exported from custom folders or third-party packages by configuring the [`imports`](/docs/api/nuxt-config#imports) section of your `nuxt.config` file.
Nuxt auto-imports functions and composables to perform [data fetching](/docs/getting-started/data-fetching), get access to the [app context](/docs/api/composables/use-nuxt-app) and [runtime config](/docs/guide/going-further/runtime-config), manage [state](/docs/getting-started/state-management) or define components and plugins.
When you are using the built-in Composition API composables provided by Vue and Nuxt, be aware that many of them rely on being called in the right _context_.
During a component lifecycle, Vue tracks the temporary instance of the current component (and similarly, Nuxt tracks a temporary instance of `nuxtApp`) via a global variable, and then unsets it in same tick. This is essential when server rendering, both to avoid cross-request state pollution (leaking a shared reference between two users) and to avoid leakage between different components.
That means that (with very few exceptions) you cannot use them outside a Nuxt plugin, Nuxt route middleware or Vue setup function. On top of that, you must use them synchronously - that is, you cannot use `await` before calling a composable, except within `<script setup>` blocks, within the setup function of a component declared with `defineNuxtComponent`, in `defineNuxtPlugin` or in `defineNuxtRouteMiddleware`, where we perform a transform to keep the synchronous context even after the `await`.
If you get an error message like `Nuxt instance is unavailable` then it probably means you are calling a Nuxt composable in the wrong place in the Vue or Nuxt lifecycle.
This will disable auto-imports completely but it's still possible to use [explicit imports](#explicit-imports) from `#imports`.
## Auto-imported Components
Nuxt also automatically imports components from your `~/components` directory, although this is configured separately from auto-importing composables and utility functions.
To disable auto-importing components from your own `~/components` directory, you can set `components.dirs` to an empty array (though note that this will not affect components added by modules).