diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php
index 51a29d8..731f2b0 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php
@@ -14,6 +14,8 @@
 /**
  * Defines the 'boolean' entity field type.
  *
+ * @property bool true|false
+ *
  * @FieldType(
  *   id = "boolean",
  *   label = @Translation("Boolean"),
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/DecimalItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/DecimalItem.php
index 00fe409..f59b452 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/DecimalItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/DecimalItem.php
@@ -10,6 +10,8 @@
 /**
  * Defines the 'decimal' field type.
  *
+ * @property double $item
+ *
  * @FieldType(
  *   id = "decimal",
  *   label = @Translation("Number (decimal)"),
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EmailItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EmailItem.php
index ca30ede..67fde59 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EmailItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EmailItem.php
@@ -12,6 +12,8 @@
 /**
  * Defines the 'email' field type.
  *
+ * @property string $email
+ *
  * @FieldType(
  *   id = "email",
  *   label = @Translation("Email"),
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EntityReferenceItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EntityReferenceItem.php
index 3d839c2..c537e5a 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EntityReferenceItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EntityReferenceItem.php
@@ -29,6 +29,9 @@
  * Supported settings (below the definition's 'settings' key) are:
  * - target_type: The entity type to reference. Required.
  *
+ * @property string|int $target_id
+ * @property \Drupal\Core\Entity\EntityInterface $entity
+ *
  * @FieldType(
  *   id = "entity_reference",
  *   label = @Translation("Entity reference"),
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/FloatItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/FloatItem.php
index 7b2234c..07b95e2 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/FloatItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/FloatItem.php
@@ -10,6 +10,8 @@
 /**
  * Defines the 'float' field type.
  *
+ * @property float $item
+ *
  * @FieldType(
  *   id = "float",
  *   label = @Translation("Number (float)"),
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/IntegerItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/IntegerItem.php
index 8469126..55a70be 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/IntegerItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/IntegerItem.php
@@ -9,6 +9,8 @@
 /**
  * Defines the 'integer' field type.
  *
+ * @property int $item
+ *
  * @FieldType(
  *   id = "integer",
  *   label = @Translation("Number (integer)"),
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/StringItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/StringItem.php
index b51764c..c9bff92 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/StringItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/StringItem.php
@@ -10,6 +10,8 @@
 /**
  * Defines the 'string' entity field type.
  *
+ * @property string $item
+ *
  * @FieldType(
  *   id = "string",
  *   label = @Translation("Text (plain)"),
diff --git a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/UriItem.php b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/UriItem.php
index 8d1d6e6..39b29ab 100644
--- a/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/UriItem.php
+++ b/core/lib/Drupal/Core/Field/Plugin/Field/FieldType/UriItem.php
@@ -10,6 +10,8 @@
 /**
  * Defines the 'uri' entity field type.
  *
+ * @property \Drupal\Core\Url $url
+ *
  * URIs are not length limited by RFC 2616, but we need to provide a sensible
  * default. There is a de-facto limit of 2000 characters in browsers and other
  * implementors, so we go with 2048.