diff --git a/phpstan.neon b/phpstan.neon
index 94d7141..9aad0db 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -3,5 +3,3 @@ parameters:
 	paths:
 		- src
 #		- tests
-	ignoreErrors:
-		- '#with no value type specified in iterable type array#'
\ No newline at end of file
diff --git a/src/SkillCalculator.php b/src/SkillCalculator.php
index 759e8cf..b5b7bff 100644
--- a/src/SkillCalculator.php
+++ b/src/SkillCalculator.php
@@ -20,8 +20,8 @@ abstract class SkillCalculator
      * Calculates new ratings based on the prior ratings and team ranks.
      *
      * @param  GameInfo $gameInfo               Parameters for the game.
-     * @param  array    $teamsOfPlayerToRatings A mapping of team players and their ratings.
-     * @param  array    $teamRanks              The ranks of the teams where 1 is first place. For a tie, repeat the number (e.g. 1, 2, 2).
+     * @param  Team[]   $teamsOfPlayerToRatings A mapping of team players and their ratings.
+     * @param  int[]    $teamRanks              The ranks of the teams where 1 is first place. For a tie, repeat the number (e.g. 1, 2, 2).
      * @return RatingContainer All the players and their new ratings.
      */
     abstract public function calculateNewRatings(
@@ -34,7 +34,7 @@ abstract class SkillCalculator
      * Calculates the match quality as the likelihood of all teams drawing.
      *
      * @param  GameInfo $gameInfo               Parameters for the game.
-     * @param  array    $teamsOfPlayerToRatings A mapping of team players and their ratings.
+     * @param  Team[]    $teamsOfPlayerToRatings A mapping of team players and their ratings.
      * @return float The quality of the match between the teams as a percentage (0% = bad, 100% = well matched).
      */
     abstract public function calculateMatchQuality(GameInfo $gameInfo, array $teamsOfPlayerToRatings): float;
diff --git a/src/TrueSkill/FactorGraphTrueSkillCalculator.php b/src/TrueSkill/FactorGraphTrueSkillCalculator.php
index 8c2c9fd..f76d7fe 100644
--- a/src/TrueSkill/FactorGraphTrueSkillCalculator.php
+++ b/src/TrueSkill/FactorGraphTrueSkillCalculator.php
@@ -26,7 +26,9 @@ class FactorGraphTrueSkillCalculator extends SkillCalculator
     {
         parent::__construct(SkillCalculatorSupportedOptions::PARTIAL_PLAY | SkillCalculatorSupportedOptions::PARTIAL_UPDATE, TeamsRange::atLeast(2), PlayersRange::atLeast(1));
     }
-
+    /**
+     * {@inheritdoc}
+     */
     public function calculateNewRatings(
         GameInfo $gameInfo,
         array $teams,
@@ -45,7 +47,9 @@ class FactorGraphTrueSkillCalculator extends SkillCalculator
 
         return $factorGraph->getUpdatedRatings();
     }
-
+    /**
+     * {@inheritdoc}
+     */
     public function calculateMatchQuality(GameInfo $gameInfo, array $teams): float
     {
         // We need to create the A matrix which is the player team assigments.
diff --git a/src/TrueSkill/Factors/GaussianWeightedSumFactor.php b/src/TrueSkill/Factors/GaussianWeightedSumFactor.php
index eff1e34..906cd20 100644
--- a/src/TrueSkill/Factors/GaussianWeightedSumFactor.php
+++ b/src/TrueSkill/Factors/GaussianWeightedSumFactor.php
@@ -217,7 +217,7 @@ class GaussianWeightedSumFactor extends GaussianFactor
         $result = (string) $sumVariable;
         $result .= ' = ';
 
-        $totalVars = is_countable($variablesToSum) ? count($variablesToSum) : 0;
+        $totalVars = count($variablesToSum);
         for ($i = 0; $i < $totalVars; $i++) {
             $isFirst = ($i == 0);
 
diff --git a/src/TrueSkill/TrueSkillFactorGraph.php b/src/TrueSkill/TrueSkillFactorGraph.php
index 888de4f..8bc4675 100644
--- a/src/TrueSkill/TrueSkillFactorGraph.php
+++ b/src/TrueSkill/TrueSkillFactorGraph.php
@@ -27,6 +27,11 @@ class TrueSkillFactorGraph extends FactorGraph
 
     private PlayerPriorValuesToSkillsLayer $priorLayer;
 
+    /**
+     * @param  GameInfo $gameInfo               Parameters for the game.
+     * @param  Team[]   $teamsOfPlayerToRatings A mapping of team players and their ratings.
+     * @param  int[]    $teamRanks              The ranks of the teams where 1 is first place. For a tie, repeat the number (e.g. 1, 2, 2).
+     */
     public function __construct(private readonly GameInfo $gameInfo, array $teams, array $teamRanks)
     {
         $this->priorLayer = new PlayerPriorValuesToSkillsLayer($this, $teams);
diff --git a/src/TrueSkill/TwoPlayerTrueSkillCalculator.php b/src/TrueSkill/TwoPlayerTrueSkillCalculator.php
index 40d223d..98adc33 100644
--- a/src/TrueSkill/TwoPlayerTrueSkillCalculator.php
+++ b/src/TrueSkill/TwoPlayerTrueSkillCalculator.php
@@ -13,6 +13,7 @@ use DNW\Skills\RatingContainer;
 use DNW\Skills\SkillCalculator;
 use DNW\Skills\SkillCalculatorSupportedOptions;
 use DNW\Skills\TeamsRange;
+use DNW\Skills\Team;
 
 /**
  * Calculates the new ratings for only two players.
@@ -27,6 +28,9 @@ class TwoPlayerTrueSkillCalculator extends SkillCalculator
         parent::__construct(SkillCalculatorSupportedOptions::NONE, TeamsRange::exactly(2), PlayersRange::exactly(1));
     }
 
+    /**
+     * {@inheritdoc}
+     */
     public function calculateNewRatings(
         GameInfo $gameInfo,
         array $teams,
diff --git a/src/TrueSkill/TwoTeamTrueSkillCalculator.php b/src/TrueSkill/TwoTeamTrueSkillCalculator.php
index f52b99c..58f0867 100644
--- a/src/TrueSkill/TwoTeamTrueSkillCalculator.php
+++ b/src/TrueSkill/TwoTeamTrueSkillCalculator.php
@@ -26,7 +26,9 @@ class TwoTeamTrueSkillCalculator extends SkillCalculator
     {
         parent::__construct(SkillCalculatorSupportedOptions::NONE, TeamsRange::exactly(2), PlayersRange::atLeast(1));
     }
-
+    /**
+     * {@inheritdoc}
+     */
     public function calculateNewRatings(GameInfo $gameInfo, array $teams, array $teamRanks): RatingContainer
     {
         Guard::argumentNotNull($gameInfo, 'gameInfo');
@@ -149,10 +151,10 @@ class TwoTeamTrueSkillCalculator extends SkillCalculator
 
         // We've verified that there's just two teams
         $team1Ratings = $teams[0]->getAllRatings();
-        $team1Count = is_countable($team1Ratings) ? count($team1Ratings) : 0;
+        $team1Count = count($team1Ratings);
 
         $team2Ratings = $teams[1]->getAllRatings();
-        $team2Count = is_countable($team2Ratings) ? count($team2Ratings) : 0;
+        $team2Count = count($team2Ratings);
 
         $totalPlayers = $team1Count + $team2Count;