> For the complete documentation index, see [llms.txt](https://doorkeeper.gitbook.io/guides/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://doorkeeper.gitbook.io/guides/ruby-on-rails/scopes.md).

# Scopes

For this guide let's create two scopes: `read` and `write`. Applications authorized with the `read` scope will be able to read public data from our API. The `write` scope will let applications change data in our API.

Go to doorkeeper's initializer and add:

{% code title="config/initializers/doorkeeper.rb" %}

```ruby
Doorkeeper.configure do
  default_scopes :read
  optional_scopes :write
    
  enforce_configured_scopes
end
```

{% endcode %}

The last line with `enforce_configured_scopes` ensures applications to be able to ask only for configured scopes defined in `default_scopes` and `optional_scopes`.