diff --git a/src/Component/Helper/FillPdfMappingHelper.php b/src/Component/Helper/FillPdfMappingHelper.php
index 1822f0f5d8654fdbabc7162dcfcc1bec96f4ac27..d1fd27474cfebb270f40355a02f5c192e5ebd898 100644
--- a/src/Component/Helper/FillPdfMappingHelper.php
+++ b/src/Component/Helper/FillPdfMappingHelper.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf\Component\Helper;
 
 /**
- * Class FillPdfMappingHelper.
+ * {@inheritdoc}
  *
  * @package Drupal\fillpdf\Component\Helper
  */
diff --git a/src/Component/Helper/FillPdfMappingHelperInterface.php b/src/Component/Helper/FillPdfMappingHelperInterface.php
index eef9ead2b2d3846f5db8b6826842810a7e376f90..44fd26c6e5caa4a3b64bc308267834998270c2bc 100644
--- a/src/Component/Helper/FillPdfMappingHelperInterface.php
+++ b/src/Component/Helper/FillPdfMappingHelperInterface.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf\Component\Helper;
 
 /**
- * Interface FillPdfMappingHelperInterface.
+ * Helper functions for handling PDF transformations.
  *
  * @package Drupal\fillpdf\Component\Helper
  */
diff --git a/src/Component/Utility/FillPdf.php b/src/Component/Utility/FillPdf.php
index d0e4e21b652ad7e78a7527496f37f6edec60c051..f04fdc36a6b192a92f1f52317a712550a8de197d 100644
--- a/src/Component/Utility/FillPdf.php
+++ b/src/Component/Utility/FillPdf.php
@@ -8,7 +8,7 @@ use GuzzleHttp\Client;
 use Symfony\Component\Process\Process;
 
 /**
- * Class FillPdf.
+ * Utility functions used throughout the module.
  *
  * @package Drupal\fillpdf\Component\Utility
  */
diff --git a/src/Controller/HandlePdfController.php b/src/Controller/HandlePdfController.php
index 8ec89340e89a912945db5fe38d8634489a0d37ea..1aabbb155895c6e5788179ed1cc1ad6e2b58e0ef 100644
--- a/src/Controller/HandlePdfController.php
+++ b/src/Controller/HandlePdfController.php
@@ -19,7 +19,7 @@ use Symfony\Component\HttpFoundation\RedirectResponse;
 use Symfony\Component\HttpFoundation\RequestStack;
 
 /**
- * Class HandlePdfController.
+ * Entry point for populating merging data into PDFs.
  */
 class HandlePdfController extends ControllerBase {
 
diff --git a/src/EntityHelper.php b/src/EntityHelper.php
index ae333a063a68ffdd05844a9e4064ec1580e55a53..fa59f399dfadd4e26dd83c7a0d296c44e127fe82 100644
--- a/src/EntityHelper.php
+++ b/src/EntityHelper.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf;
 
 /**
- * Class EntityHelper.
+ * {@inheritdoc}
  *
  * @package Drupal\fillpdf
  * @deprecated in fillpdf:8.x-4.7 and is removed from fillpdf:8.x-5.0. Applies
diff --git a/src/EntityHelperInterface.php b/src/EntityHelperInterface.php
index 5b259c3e60a06ab6889916bd2007d603bb67393f..04f2ef9bc06479a6b08d835c6b8d7c178bc117c1 100644
--- a/src/EntityHelperInterface.php
+++ b/src/EntityHelperInterface.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf;
 
 /**
- * Interface EntityHelperInterface.
+ * Utility class for interacting with FillPDF forms.
  *
  * @package Drupal\fillpdf
  * @deprecated in fillpdf:8.x-4.7 and is removed from fillpdf:8.x-5.0. Applies
diff --git a/src/ExportableContentEntityInterface.php b/src/ExportableContentEntityInterface.php
index 37d17bfb90cd150d1e2c188413d2522c162e5301..2e1cf4b71b8722fb34817641eb1a3642bccd88ab 100644
--- a/src/ExportableContentEntityInterface.php
+++ b/src/ExportableContentEntityInterface.php
@@ -5,7 +5,7 @@ namespace Drupal\fillpdf;
 use Drupal\Core\Entity\ContentEntityInterface;
 
 /**
- * Interface ExportableContentEntityInterface.
+ * Lists exportable fields for implementing entities.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/FillPdfAccessHelper.php b/src/FillPdfAccessHelper.php
index 543a056c5617bce33f0e3b5d456fdded31990ba9..9589b07053721bab0a9c1471a37ffcb8163c606c 100644
--- a/src/FillPdfAccessHelper.php
+++ b/src/FillPdfAccessHelper.php
@@ -7,7 +7,7 @@ use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Url;
 
 /**
- * Class FillPdfAccessHelper.
+ * {@inheritdoc}
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/FillPdfAccessHelperInterface.php b/src/FillPdfAccessHelperInterface.php
index 730b569b62bca518808faf56b3beeda1233cc46a..4b529ad3873daf76d14d9bbbf4515f46a6e6b3ab 100644
--- a/src/FillPdfAccessHelperInterface.php
+++ b/src/FillPdfAccessHelperInterface.php
@@ -6,7 +6,7 @@ use Drupal\Core\Session\AccountInterface;
 use Drupal\Core\Url;
 
 /**
- * Interface FillPdfAccessHelperInterface.
+ * Checks whether the configured permissions allow merging a PDF.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/FillPdfAdminFormHelperInterface.php b/src/FillPdfAdminFormHelperInterface.php
index bcf42b8af24ae01733e0751d4e2a3c27f89dbf94..aa0a0493e3ca96d501457f4e5542e2df365422bf 100644
--- a/src/FillPdfAdminFormHelperInterface.php
+++ b/src/FillPdfAdminFormHelperInterface.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf;
 
 /**
- * Interface FillPdfAdminFormHelperInterface.
+ * Common methods used on admin screens.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/FillPdfFormFieldInterface.php b/src/FillPdfFormFieldInterface.php
index 19cf60cc7327b2e80ed3750978a6bd5b8bf9d806..dad6fe53694a5ef23c4b63da793858aeac883a8f 100644
--- a/src/FillPdfFormFieldInterface.php
+++ b/src/FillPdfFormFieldInterface.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf;
 
 /**
- * Interface FillPdfFormFieldInterface.
+ * Represents a fillable field on a FillPDF form.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/FillPdfFormFieldViewsData.php b/src/FillPdfFormFieldViewsData.php
index 578534b736c2d0058c6f2b2a13254d7b0822c47d..54b5d3c871b63f9bdaf8847818824477934963a0 100644
--- a/src/FillPdfFormFieldViewsData.php
+++ b/src/FillPdfFormFieldViewsData.php
@@ -5,7 +5,7 @@ namespace Drupal\fillpdf;
 use Drupal\views\EntityViewsData;
 
 /**
- * Class FillPdfFormFieldViewsData.
+ * Exposes form field metadata for the Views integration.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/FillPdfFormInterface.php b/src/FillPdfFormInterface.php
index bdf8585f81f35c771735d114cd3cdbac7b5f95bb..42f4382f659ec0bd94c93b44114dffcdd51f92e7 100644
--- a/src/FillPdfFormInterface.php
+++ b/src/FillPdfFormInterface.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf;
 
 /**
- * Interface FillPdfFormInterface.
+ * Represents a fillable PDF form.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/FillPdfFormViewsData.php b/src/FillPdfFormViewsData.php
index 06c269f08f7810ec56aaf258d0418b14d87872e5..80d246e9db9306899f926be7d58ef8c3d7532c1e 100644
--- a/src/FillPdfFormViewsData.php
+++ b/src/FillPdfFormViewsData.php
@@ -5,7 +5,7 @@ namespace Drupal\fillpdf;
 use Drupal\views\EntityViewsData;
 
 /**
- * Class FillPdfFormViewsData.
+ * Exposes form metadata for the Views integration.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/Form/FillPdfAdminFormBase.php b/src/Form/FillPdfAdminFormBase.php
index f99a3f1ec40b0ab3e17b321860fc14ef48ea052a..59d59ca77b9cca4f8e6f6a72c73306c2757c6341 100644
--- a/src/Form/FillPdfAdminFormBase.php
+++ b/src/Form/FillPdfAdminFormBase.php
@@ -7,7 +7,7 @@ use Drupal\Core\Form\FormBase;
 @trigger_error('FillPdfAdminFormBase is deprecated in fillpdf:8.x-4.7 and is removed from fillpdf:8.x-5.0. Use \Drupal\Core\Form\FormBase instead. See https://www.drupal.org/project/fillpdf/issues/3044743', E_USER_DEPRECATED);
 
 /**
- * Class FillPdfAdminFormBase.
+ * Base class for administrative forms.
  *
  * @package Drupal\fillpdf\Form
  *
diff --git a/src/Form/FillPdfFormConfirmFormBase.php b/src/Form/FillPdfFormConfirmFormBase.php
index 12e9d238ba507082f4d15a61d1312030e28de6d2..99e7d167c9d75586e98af01f7d7f41fd8e66d4a7 100644
--- a/src/Form/FillPdfFormConfirmFormBase.php
+++ b/src/Form/FillPdfFormConfirmFormBase.php
@@ -6,7 +6,7 @@ use Drupal\Core\Entity\ContentEntityConfirmFormBase;
 use Drupal\Core\Form\FormStateInterface;
 
 /**
- * Class FillPdfFormConfirmFormBase.
+ * Base class for confirmation forms.
  *
  * @package Drupal\fillpdf\Form
  */
diff --git a/src/InputHelper.php b/src/InputHelper.php
index 0a11f4bc4a9d4287e5caee754e82c8553f4164b8..f0ab39b18a19f4c1f2549805829b440e96b7ce85 100644
--- a/src/InputHelper.php
+++ b/src/InputHelper.php
@@ -10,7 +10,7 @@ use Drupal\fillpdf\Entity\FillPdfFormField;
 use Drupal\fillpdf\Plugin\PdfBackendManager;
 
 /**
- * Class InputHelper.
+ * {@inheritdoc}
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/InputHelperInterface.php b/src/InputHelperInterface.php
index 60b263699f1346ee4aab0b42c62aedc4f35465e8..bb9258d671844b16ea6708c799dac23e2500b676 100644
--- a/src/InputHelperInterface.php
+++ b/src/InputHelperInterface.php
@@ -5,7 +5,7 @@ namespace Drupal\fillpdf;
 use Drupal\file\FileInterface;
 
 /**
- * Interface InputHelperInterface.
+ * Helper methods for PDF uploads.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/OutputHandler.php b/src/OutputHandler.php
index 37de557b8224c71f463c35ba901d56799cd133a1..36bc821a32147d2fce246686a7e8122191df5f8c 100644
--- a/src/OutputHandler.php
+++ b/src/OutputHandler.php
@@ -10,7 +10,7 @@ use Psr\Log\LoggerInterface;
 use Drupal\Core\File\FileSystemInterface;
 
 /**
- * Class OutputHandler.
+ * {@inheritdoc}
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/Serializer.php b/src/Serializer.php
index c1c724e78fc0b377045bc114500851d30a261545..6538b7ab1a52a286b39a5b7b3add72af20aa4a38 100644
--- a/src/Serializer.php
+++ b/src/Serializer.php
@@ -6,7 +6,7 @@ use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Symfony\Component\Serializer\Serializer as SymfonySerializer;
 
 /**
- * Class Serializer.
+ * {@inheritdoc}
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/SerializerInterface.php b/src/SerializerInterface.php
index fe5be516bb84f9a715f519503b922bcc613266ae..d693151b69384c786886986fe9cbde11de7b3455 100644
--- a/src/SerializerInterface.php
+++ b/src/SerializerInterface.php
@@ -3,7 +3,7 @@
 namespace Drupal\fillpdf;
 
 /**
- * Interface SerializerInterface.
+ * Handles exporting and importing FillPDF forms.
  *
  * @package Drupal\fillpdf
  */
diff --git a/src/Service/BackendProxy.php b/src/Service/BackendProxy.php
index f908267b2109d1d8796d85e837423f4038930f18..ac850e6c0c9e9d830f49686b7a8e615ad7d5410d 100644
--- a/src/Service/BackendProxy.php
+++ b/src/Service/BackendProxy.php
@@ -11,7 +11,7 @@ use Drupal\fillpdf\Plugin\PdfBackendManager;
 use Drupal\fillpdf\TokenResolverInterface;
 
 /**
- * BackendProxy service.
+ * {@inheritdoc}
  */
 class BackendProxy implements BackendProxyInterface {
 
diff --git a/src/TokenResolver.php b/src/TokenResolver.php
index f51b3f896564ec9c29880ca3857e5845fcec038a..bbc6a02a84a6dfbb51c5658ce31d3b231a0066bd 100644
--- a/src/TokenResolver.php
+++ b/src/TokenResolver.php
@@ -15,7 +15,7 @@ use Drupal\fillpdf\FieldMapping\TextFieldMapping;
 use Drupal\token\TokenEntityMapperInterface;
 
 /**
- * Class TokenResolver.
+ * {@inheritdoc}
  *
  * @package Drupal\fillpdf
  */