diff --git a/src/Core/AES.php b/src/Core/AES.php
index de44f9c6..cade27d7 100644
--- a/src/Core/AES.php
+++ b/src/Core/AES.php
@@ -190,6 +190,15 @@ public static function invSbox(ParagonIE_Sodium_Core_AES_Block $q)
         self::processInversion($q);
     }
 
+    /**
+     * This is some boilerplate code needed to invert an S-box. Rather than repeat the code
+     * twice, I moved it to a protected method.
+     *
+     * Mutates $q
+     *
+     * @param ParagonIE_Sodium_Core_AES_Block $q
+     * @return void
+     */
     protected static function processInversion(ParagonIE_Sodium_Core_AES_Block $q)
     {
         $q0 = (~$q[0]) & self::U32_MAX;
@@ -271,6 +280,7 @@ public static function keySchedule($key)
             $skey[($i << 1)] = $tmp & self::U32_MAX;
             $skey[($i << 1) + 1] = $tmp & self::U32_MAX;
             if (++$j === $nk) {
+                /** @psalm-suppress LoopInvalidation */
                 $j = 0;
                 ++$k;
             }
@@ -395,6 +405,11 @@ public static function bitsliceEncryptBlock(
         self::addRoundKey($q, $skey, ($skey->getNumRounds() << 3));
     }
 
+    /**
+     * @param ParagonIE_Sodium_Core_AES_Expanded $skey
+     * @param ParagonIE_Sodium_Core_AES_Block $q
+     * @return void
+     */
     public static function bitsliceDecryptBlock(
         ParagonIE_Sodium_Core_AES_Expanded $skey,
         ParagonIE_Sodium_Core_AES_Block $q
diff --git a/src/Core/AES/Expanded.php b/src/Core/AES/Expanded.php
index 42080ff2..6deb9d59 100644
--- a/src/Core/AES/Expanded.php
+++ b/src/Core/AES/Expanded.php
@@ -4,6 +4,4 @@ class ParagonIE_Sodium_Core_AES_Expanded extends ParagonIE_Sodium_Core_AES_KeySc
 {
     /** @var bool $expanded */
     protected $expanded = true;
-
-
-}
\ No newline at end of file
+}
diff --git a/src/Core/AES/KeySchedule.php b/src/Core/AES/KeySchedule.php
index db32e60f..9c1b0dd9 100644
--- a/src/Core/AES/KeySchedule.php
+++ b/src/Core/AES/KeySchedule.php
@@ -3,7 +3,7 @@
 class ParagonIE_Sodium_Core_AES_KeySchedule
 {
     /** @var array<int, int> $skey -- has size 120 */
-    private $skey;
+    protected $skey;
 
     /** @var bool $expanded */
     protected $expanded = false;
@@ -21,11 +21,20 @@ public function __construct(array $skey, $numRounds = 10)
         $this->numRounds = $numRounds;
     }
 
+    /**
+     * Get a value at an arbitrary index. Mostly used for unit testing.
+     *
+     * @param int $i
+     * @return int
+     */
     public function get($i)
     {
         return $this->skey[$i];
     }
 
+    /**
+     * @return int
+     */
     public function getNumRounds()
     {
         return $this->numRounds;