diff --git a/src/Plugin/migrate/process/DefaultEntityValue.php b/src/Plugin/migrate/process/DefaultEntityValue.php
index d7a584b914b4477b88fe93d33b4f8f7122999203..58bc4ee86401cc7ef74cd94ee1cf007371cf5a44 100644
--- a/src/Plugin/migrate/process/DefaultEntityValue.php
+++ b/src/Plugin/migrate/process/DefaultEntityValue.php
@@ -10,9 +10,11 @@ use Drupal\migrate\Row;
 /**
  * Returns EntityLookup for a given default value if input is empty.
  *
- * @see \Drupal\migrate_plus\Plugin\migrate\process\EntityLookup
+ * Available configuration keys:
+ * - default_value: The default value that will be used as for the entity lookup.
+ * For additional configuration keys, refer to the parent class.
  *
- * Example usage with full configuration:
+ * Example:
  * @code
  * process:
  *   uid:
@@ -28,6 +30,12 @@ use Drupal\migrate\Row;
  *       default_value: editorial
  * @endcode
  *
+ * In this example, it will look up the source value of author in the users
+ * migration and if not found, use entity lookup to find a user with "editorial"
+ * username.
+ *
+ * @see \Drupal\migrate_plus\Plugin\migrate\process\EntityLookup
+ *
  * @MigrateProcessPlugin(
  *   id = "default_entity_value",
  *   handle_multiples = TRUE
diff --git a/src/Plugin/migrate/process/EntityValue.php b/src/Plugin/migrate/process/EntityValue.php
index 6bb6cd5974c7051f2a7adead36835bb43a54df03..9e0022a0cde7f3b784a9b67017c7eb3cce26b152 100644
--- a/src/Plugin/migrate/process/EntityValue.php
+++ b/src/Plugin/migrate/process/EntityValue.php
@@ -23,7 +23,12 @@ use Symfony\Component\DependencyInjection\ContainerInterface;
  * specified. Optionally, the field property should be specified if it is not
  * the default of 'value'.
  *
- * For content entities, if a langcode is given, that translation is loaded.
+ * Available configuration keys:
+ * - entity_type: The entity type ID to query for.
+ * - field_name: The machine name of the field to be extracted from the loaded
+ *   entity.
+ * - langcode: (optional) The language code of entity translation. If given, the
+ *   entity translation is loaded. It can only be used with content entities.
  *
  * Example:
  * @code
@@ -32,10 +37,13 @@ use Symfony\Component\DependencyInjection\ContainerInterface;
  *     plugin: entity_value
  *     source: field_noderef/0/target_id
  *     entity_type: node
- *     langcode: en
+ *     langcode: es
  *     field_name: field_foo
  * @endcode
  *
+ * In this example field_foo field value will be retrieved from Spanish
+ * translation of the loaded node.
+ *
  * @MigrateProcessPlugin(
  *   id = "entity_value",
  * )
diff --git a/src/Plugin/migrate/process/Service.php b/src/Plugin/migrate/process/Service.php
index 009d4258c30d4c20020949e7438ac9a5aa4c8473..d085640f0072732ed2c0063e2abf7f2cd7b43867 100644
--- a/src/Plugin/migrate/process/Service.php
+++ b/src/Plugin/migrate/process/Service.php
@@ -11,6 +11,15 @@ use Symfony\Component\DependencyInjection\ContainerInterface;
 /**
  * Provides a plugin to use a callable from a service class.
  *
+ * Available configuration keys:
+ * - service: The ID of the service (e.g. file.mime_type.guesser).
+ * - method: The name of the service public method.
+ * All options for the callback plugin can be used, except for 'callable',
+ * which will be ignored.
+ *
+ * Since Drupal 9.2.0, it is possible to supply multiple arguments using
+ * unpack_source property. See: https://www.drupal.org/node/3205079
+ *
  * Examples:
  *
  * @code
@@ -40,12 +49,6 @@ use Symfony\Component\DependencyInjection\ContainerInterface;
  *       - constants/slash
  * @endcode
  *
- * Since Drupal 9.2.0, it is possible to supply multiple arguments using
- * unpack_source property. See: https://www.drupal.org/node/3205079
- *
- * All options for the callback plugin can be used, except for 'callable',
- * which will be ignored.
- *
  * @see \Drupal\migrate\Plugin\migrate\process\Callback
  *
  * @MigrateProcessPlugin(
diff --git a/src/Plugin/migrate/process/StrReplace.php b/src/Plugin/migrate/process/StrReplace.php
index cddd2c7d28769cedab3055124e1f2d318c2fbbd2..08dece79fd1471e3beb3b4f152be478e71067b1e 100644
--- a/src/Plugin/migrate/process/StrReplace.php
+++ b/src/Plugin/migrate/process/StrReplace.php
@@ -9,58 +9,60 @@ use Drupal\migrate\ProcessPluginBase;
 use Drupal\migrate\Row;
 
 /**
- * Uses the str_replace() method on a source string.
+ * Uses either str_replace() or preg_replace() function on a source string.
  *
- * @MigrateProcessPlugin(
- *   id = "str_replace"
- * )
+ * Available configuration keys:
+ * - search: The value or pattern being searched for. It can be either a string
+ *   or an array with strings.
+ * - replace: The replacement value that replaces found search values. It can be
+ *   either a string or an array with strings.
+ * - regex: (optional) If not empty, then preg_replace() function will be used
+ *   instead of str_replace(). Defaults to FALSE.
+ * - case_insensitive: (optional) If not empty, then str_ireplace() function
+ *   will be used instead of str_replace(). Defaults to FALSE. Ignored if
+ *   'regex' is enabled.
  *
- * @codingStandardsIgnoreStart
+ * Depending on the value of 'regex', the rules for
+ * @link http://php.net/manual/function.str-replace.php str_replace @endlink
+ * or
+ * @link http://php.net/manual/function.preg-replace.php preg_replace @endlink
+ * apply. This means that you can provide arrays as values, your replace string
+ * can include backreferences, etc.
  *
  * To do a simple hardcoded string replace, use the following:
  * @code
  * field_text:
  *   plugin: str_replace
  *   source: text
- *   search: foo
- *   replace: bar
+ *   search: et
+ *   replace: that
  * @endcode
- * If the value of text is "vero eos et accusam et justo vero" in source, foo is
- * "et" in search and bar is "that" in replace, field_text will be "vero eos
- * that accusam that justo vero".
+ * If the value of text is "vero eos et accusam et justo vero" in source,
+ * field_text will be "vero eos that accusam that justo vero".
  *
- * Case insensitive searches can be achieved using the following:
+ * Case-insensitive searches can be achieved using the following:
  * @code
  * field_text:
  *   plugin: str_replace
  *   case_insensitive: true
  *   source: text
- *   search: foo
- *   replace: bar
+ *   search: vero
+ *   replace: that
  * @endcode
- * If the value of text is "VERO eos et accusam et justo vero" in source, foo is
- * "vero" in search and bar is "that" in replace, field_text will be "that eos
- * et accusam et justo that".
+ * If the value of text is "VERO eos et accusam et justo vero" in source,
+ * field_text will be "that eos et accusam et justo that".
  *
- * Also regular expressions can be matched using:
+ * Also, regular expressions can be matched using:
  * @code
  * field_text:
  *   plugin: str_replace
  *   regex: true
  *   source: text
- *   search: foo
- *   replace: bar
+ *   search: /[0-9]{3}/
+ *   replace: the
  * @endcode
  * If the value of text is "vero eos et 123 accusam et justo 123 duo" in source,
- * foo is "/[0-9]{3}/" in search and bar is "the" in replace, field_text will be
- * "vero eos et the accusam et justo the duo".
- *
- * Depending on the value of 'regex', the rules for
- * @link http://php.net/manual/function.str-replace.php str_replace @endlink
- * or
- * @link http://php.net/manual/function.preg-replace.php preg_replace @endlink
- * apply. This means that you can provide arrays as values, your replace string
- * can include backreferences, etc.
+ * field_text will be "vero eos et the accusam et justo the duo".
  *
  * Multiple values can be matched like this:
  * @code
@@ -77,14 +79,14 @@ use Drupal\migrate\Row;
  *   plugin: str_replace
  *   regex: true
  *   source: text
- *   search: foo
- *   replace: bar
+ *   search: /@(\S+)/
+ *   replace: $1
  * @endcode
- * If the value of text is "@username" in source,
- * foo is "/@(\S+)/" in search and bar is "$1" in replace, field_text will be
- * "username".
+ * If the value of text is "@username" in source, field_text will be "username".
  *
- * @codingStandardsIgnoreEnd
+ * @MigrateProcessPlugin(
+ *   id = "str_replace"
+ * )
  */
 class StrReplace extends ProcessPluginBase {