diff --git a/includes/search/SearchEngine.php b/includes/search/SearchEngine.php
index 07dab05053d..f03b730ba01 100644
--- a/includes/search/SearchEngine.php
+++ b/includes/search/SearchEngine.php
@@ -62,6 +62,7 @@ abstract class SearchEngine {
 
 	/** @var bool */
 	protected $showSuggestion = true;
+	/** @var string */
 	private $sort = self::DEFAULT_SORT;
 
 	/** @var array Feature values */
diff --git a/includes/search/SearchHighlighter.php b/includes/search/SearchHighlighter.php
index 259d0e48dba..4406b721bec 100644
--- a/includes/search/SearchHighlighter.php
+++ b/includes/search/SearchHighlighter.php
@@ -38,6 +38,7 @@ class SearchHighlighter {
 	public const DEFAULT_CONTEXT_LINES = 2;
 	public const DEFAULT_CONTEXT_CHARS = 75;
 
+	/** @var bool */
 	protected $mCleanWikitext = true;
 
 	/**
diff --git a/includes/search/SearchMySQL.php b/includes/search/SearchMySQL.php
index 65d5e44c556..ddbab89c4ac 100644
--- a/includes/search/SearchMySQL.php
+++ b/includes/search/SearchMySQL.php
@@ -36,8 +36,10 @@ use Wikimedia\Rdbms\SelectQueryBuilder;
  * @ingroup Search
  */
 class SearchMySQL extends SearchDatabase {
+	/** @var bool */
 	protected $strictMatching = true;
 
+	/** @var int|null */
 	private static $mMinSearchLength;
 
 	/**
diff --git a/includes/search/SearchResultSet.php b/includes/search/SearchResultSet.php
index b0a962a6f57..7f28e3aee3b 100644
--- a/includes/search/SearchResultSet.php
+++ b/includes/search/SearchResultSet.php
@@ -30,6 +30,7 @@ class SearchResultSet extends BaseSearchResultSet {
 
 	use SearchResultSetTrait;
 
+	/** @var bool */
 	protected $containedSyntax = false;
 
 	/**
diff --git a/tests/phpunit/mocks/search/MockSearchResult.php b/tests/phpunit/mocks/search/MockSearchResult.php
index ec60cf32cf6..0ff1ceca6bd 100644
--- a/tests/phpunit/mocks/search/MockSearchResult.php
+++ b/tests/phpunit/mocks/search/MockSearchResult.php
@@ -1,8 +1,11 @@
 <?php
 
 class MockSearchResult extends RevisionSearchResult {
+	/** @var bool */
 	private $isMissingRevision = false;
+	/** @var bool */
 	private $isBrokenTitle = false;
+	/** @var string */
 	private $interwikiPrefix = '';
 
 	public function isMissingRevision() {