src/ResourceType/ResourceTypeRepository.php | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/ResourceType/ResourceTypeRepository.php b/src/ResourceType/ResourceTypeRepository.php
index 128eb47..53c1e4c 100644
--- a/src/ResourceType/ResourceTypeRepository.php
+++ b/src/ResourceType/ResourceTypeRepository.php
@@ -105,6 +105,17 @@ class ResourceTypeRepository implements ResourceTypeRepositoryInterface {
     return $cached ? $cached->data : $resource_types;
   }
 
+  /**
+   * Creates a ResourceType value object for the given entity type + bundle.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeInterface $entity_type
+   *   The entity type to create a JSON API resource type for.
+   * @param string $bundle
+   *   The entity type bundle to create a JSON API resource type for.
+   *
+   * @return \Drupal\jsonapi\ResourceType\ResourceType
+   *   A JSON API resource type.
+   */
   protected function createResourceType(EntityTypeInterface $entity_type, $bundle) {
     $raw_fields = $this->getAllFieldNames($entity_type, $bundle);
     return new ResourceType(