diff --git a/src/WPIntegration/Autoload.php b/src/WPIntegration/Autoload.php
index 384fd00..e61398c 100644
--- a/src/WPIntegration/Autoload.php
+++ b/src/WPIntegration/Autoload.php
@@ -27,7 +27,7 @@ final class Autoload {
 	/**
 	 * A list of the classes this autoloader handles.
 	 *
-	 * @var string[] => true
+	 * @var array<string, true>
 	 */
 	private static $supported_classes = [
 		'PHPUnit\\Framework\\MockObject\\Builder\\NamespaceMatch'  => true,
diff --git a/tests/BrainMonkey/TestCaseTest.php b/tests/BrainMonkey/TestCaseTest.php
index 4f6265c..1fd8885 100644
--- a/tests/BrainMonkey/TestCaseTest.php
+++ b/tests/BrainMonkey/TestCaseTest.php
@@ -182,7 +182,7 @@ public function testMakeDoubleForUnavailableClass( $class_name ) {
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<string, array<string>>
 	 */
 	public function dataMakeDoubleForUnavailableClass() {
 		return [
@@ -218,7 +218,7 @@ public function testMakeDoubleForUnavailableClassThrowsExceptionWithInvalidName(
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<string, array<string>>
 	 */
 	public function dataMakeDoubleForUnavailableClassThrowsExceptionWithInvalidName() {
 		return [
diff --git a/tests/BrainMonkey/YoastTestCaseTest.php b/tests/BrainMonkey/YoastTestCaseTest.php
index 53695c2..720f5e7 100644
--- a/tests/BrainMonkey/YoastTestCaseTest.php
+++ b/tests/BrainMonkey/YoastTestCaseTest.php
@@ -28,7 +28,7 @@ public function testStubGetBlogInfo( $show, $expected ) {
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<string, array<string, string>>
 	 */
 	public function dataStubGetBlogInfo() {
 		return [
@@ -125,9 +125,9 @@ public function testStubWpKsesPost() {
 	 *
 	 * @dataProvider dataStubWpParseArgs
 	 *
-	 * @param array $settings Value for settings to pass to the function.
-	 * @param array $defaults Value for defaults to pass to the function.
-	 * @param array $expected Expected return value.
+	 * @param array<string, mixed> $settings Value for settings to pass to the function.
+	 * @param array<string, mixed> $defaults Value for defaults to pass to the function.
+	 * @param array<string, mixed> $expected Expected return value.
 	 *
 	 * @return void
 	 */
@@ -138,7 +138,7 @@ public function testStubWpParseArgs( $settings, $defaults, $expected ) {
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<string, array<string, array<string, mixed>>>
 	 */
 	public function dataStubWpParseArgs() {
 		return [
@@ -219,7 +219,7 @@ public function testStubWpStripAllTags( $text, $remove_breaks, $expected ) {
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<string, array<string, string|bool>>
 	 */
 	public function dataStubWpStripAllTags() {
 		return [
@@ -271,7 +271,7 @@ public function dataStubWpStripAllTags() {
 	 *
 	 * @dataProvider dataStubWpSlash
 	 *
-	 * @param string $input Value to pass to the function.
+	 * @param mixed $input Value to pass to the function.
 	 *
 	 * @return void
 	 */
@@ -282,7 +282,7 @@ public function testStubWpSlash( $input ) {
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<string, array<string, mixed>>
 	 */
 	public function dataStubWpSlash() {
 		return [
@@ -308,8 +308,8 @@ public function dataStubWpSlash() {
 	 *
 	 * @dataProvider dataStubWpUnslash
 	 *
-	 * @param string $input    Value to pass to the function.
-	 * @param string $expected Expected return value.
+	 * @param mixed $input    Value to pass to the function.
+	 * @param mixed $expected Expected return value.
 	 *
 	 * @return void
 	 */
@@ -320,7 +320,7 @@ public function testStubWpUnslash( $input, $expected ) {
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<string, array<string, mixed>>
 	 */
 	public function dataStubWpUnslash() {
 		return [
diff --git a/tests/Helpers/ExpectOutputHelperTest.php b/tests/Helpers/ExpectOutputHelperTest.php
index d56c8ff..6ca7f58 100644
--- a/tests/Helpers/ExpectOutputHelperTest.php
+++ b/tests/Helpers/ExpectOutputHelperTest.php
@@ -123,7 +123,7 @@ public function testMatchingSubstringsWithMismatchedLineEndingsAmount( $expected
 	/**
 	 * Data provider.
 	 *
-	 * @return array
+	 * @return array<array<string>>
 	 */
 	public function dataMatchingSubstringsMismatchedLineEndings() {
 		return [
@@ -231,7 +231,7 @@ public function testNormalizeLineEndings( $input, $expected ) {
 	/**
 	 * Data provider for the `testNormalizeLineEndings()` test.
 	 *
-	 * @return array
+	 * @return array<string, array<string>>
 	 */
 	public function dataNormalizeLineEndings() {
 		return [