diff --git a/core/modules/field/lib/Drupal/field/FieldInfo.php b/core/modules/field/lib/Drupal/field/FieldInfo.php
index 847de3a025e0623c610379c3e7e4e5f80f2e5291..3e4d6aabf2b5bb9c7df743240093078410996973 100644
--- a/core/modules/field/lib/Drupal/field/FieldInfo.php
+++ b/core/modules/field/lib/Drupal/field/FieldInfo.php
@@ -71,7 +71,7 @@ class FieldInfo {
   /**
    * List of $field structures keyed by ID. Includes deleted fields.
    *
-   * @var array
+   * @var \Drupal\field\FieldInterface[]
    */
   protected $fieldsById = array();
 
@@ -166,7 +166,7 @@ public function flush() {
   /**
    * Collects a lightweight map of fields across bundles.
    *
-   * @return
+   * @return array
    *   An array keyed by entity type. Each value is an array which keys are
    *   field names and value is an array with two entries:
    *   - type: The field type.
@@ -218,8 +218,8 @@ public function getFieldMap() {
   /**
    * Returns all active fields, including deleted ones.
    *
-   * @return
-   *   An array of field definitions, keyed by field ID.
+   * @return \Drupal\field\FieldInterface[]
+   *   An array of field entities, keyed by field ID.
    */
   public function getFields() {
     // Read from the "static" cache.
@@ -256,10 +256,10 @@ public function getFields() {
   /**
    * Retrieves all active, non-deleted instances definitions.
    *
-   * @param $entity_type
+   * @param string $entity_type
    *   (optional) The entity type.
    *
-   * @return
+   * @return array
    *   If $entity_type is not set, all instances keyed by entity type and bundle
    *   name. If $entity_type is set, all instances for that entity type, keyed
    *   by bundle name.
@@ -309,7 +309,7 @@ public function getInstances($entity_type = NULL) {
    * @param string $field_name
    *   The field name.
    *
-   * @return
+   * @return \Drupal\field\FieldInterface|null
    *   The field definition, or NULL if no field was found.
    */
   public function getField($entity_type, $field_name) {
@@ -340,15 +340,15 @@ public function getField($entity_type, $field_name) {
   }
 
   /**
-   * Returns a field definition from a field ID.
+   * Returns a field entity from a field ID.
    *
    * This method only retrieves active fields, deleted or not.
    *
-   * @param $field_id
+   * @param string $field_id
    *   The field ID.
    *
-   * @return
-   *   The field definition, or NULL if no field was found.
+   * @return \Drupal\field\FieldInterface|null
+   *   The field entity, or NULL if no field was found.
    */
   public function getFieldById($field_id) {
     // Read from the "static" cache.
@@ -386,13 +386,13 @@ public function getFieldById($field_id) {
    * The function also populates the corresponding field definitions in the
    * "static" cache.
    *
-   * @param $entity_type
+   * @param string $entity_type
    *   The entity type.
-   * @param $bundle
+   * @param string $bundle
    *   The bundle name.
    *
-   * @return
-   *   The array of instance definitions, keyed by field name.
+   * @return \Drupal\field\FieldInstanceInterface[]
+   *   An array of field instance entities, keyed by field name.
    */
   public function getBundleInstances($entity_type, $bundle) {
     // Read from the "static" cache.
@@ -496,7 +496,7 @@ public function getBundleInstances($entity_type, $bundle) {
   }
 
   /**
-   * Returns an array of instance data for a specific field and bundle.
+   * Returns a field instance.
    *
    * @param string $entity_type
    *   The entity type for the instance.
@@ -505,9 +505,8 @@ public function getBundleInstances($entity_type, $bundle) {
    * @param string $field_name
    *   The field name for the instance.
    *
-   * @return array
-   *   An associative array of instance data for the specific field and bundle;
-   *   NULL if the instance does not exist.
+   * @return \Drupal\field\FieldInstanceInterface|null
+   *   The field instance entity, or NULL if it does not exist.
    */
   function getInstance($entity_type, $bundle, $field_name) {
     $info = $this->getBundleInstances($entity_type, $bundle);
@@ -519,12 +518,12 @@ function getInstance($entity_type, $bundle, $field_name) {
   /**
    * Retrieves the "extra fields" for a bundle.
    *
-   * @param $entity_type
+   * @param string $entity_type
    *   The entity type.
-   * @param $bundle
+   * @param string $bundle
    *   The bundle name.
    *
-   * @return
+   * @return array
    *   The array of extra fields.
    */
   public function getBundleExtraFields($entity_type, $bundle) {
@@ -555,13 +554,13 @@ public function getBundleExtraFields($entity_type, $bundle) {
   }
 
   /**
-   * Prepares a field definition for the current run-time context.
+   * Prepares a field for the current run-time context.
    *
-   * @param $field
-   *   The raw field structure as read from the database.
+   * @param \Drupal\field\FieldInterface $field
+   *   The field entity to update.
    *
-   * @return
-   *   The field definition completed for the current runtime context.
+   * @return \Drupal\field\FieldInterface
+   *   The field that was prepared.
    */
   public function prepareField(FieldInterface $field) {
     // Make sure all expected field settings are present.
@@ -571,13 +570,13 @@ public function prepareField(FieldInterface $field) {
   }
 
   /**
-   * Prepares an instance definition for the current run-time context.
+   * Prepares a field instance for the current run-time context.
    *
    * @param \Drupal\field\FieldInstanceInterface $instance
-   *   The instance definition.
+   *   The field instance entity to prepare.
    *
-   * @return
-   *   The field instance array completed for the current runtime context.
+   * @return \Drupal\field\FieldInstanceInterface
+   *   The field instance that was prepared.
    */
   public function prepareInstance(FieldInstanceInterface $instance) {
     // Make sure all expected instance settings are present.