Update documentation

docs/master/digging-deeper/feature-toggles.md

@@ -1,6 +1,6 @@
 # Feature Toggles
 
-Lighthouse allows you to conditionally show or hide elements of your schema.
+Lighthouse allows you to conditionally show or hide elements (fields, types, arguments or input fields) of your schema.
 
 ## @show and @hide
 
@@ -27,7 +27,7 @@ type Query {
 
 ## @feature
 
-The [@feature](../api-reference/directives.md#feature) directive allows to include fields in the schema depending
+The [@feature](../api-reference/directives.md#feature) directive allows to include fields, types, arguments or input fields, in the schema depending
 on a [Laravel Pennant](https://laravel.com/docs/pennant) feature.
 
 For example, you might want a new experimental field only to be available when the according feature is active:
@@ -57,6 +57,21 @@ type Query {
 }
 ```
 
+## Conditional Type Inclusion
+
+When you conditionally include a type, using [@show](../api-reference/directives.md#show), [@hide](../api-reference/directives.md#hide) or [@feature](../api-reference/directives.md#feature), any fields using it must 
+also be conditionally included, otherwise the schema might be invalid in case the type is missing.
+
+```graphql
+type ExperimentalType @feature(name: "new-api") {
+  field: String!
+}
+
+type Query {
+  experimentalField: ExperimentalType @feature(name: "new-api")
+}
+```
+
 ## Interaction With Schema Cache
 
 [@show](../api-reference/directives.md#show) and [@hide](../api-reference/directives.md#hide) work by manipulating the schema.