diff --git a/src/Differ/DiffCollector.php b/src/Differ/DiffCollector.php
index 57f0973..f1f1a9f 100644
--- a/src/Differ/DiffCollector.php
+++ b/src/Differ/DiffCollector.php
@@ -9,7 +9,7 @@
 use O0h\PhpAstCheckDiff\Value\Diff;
 
 /**
- * @phpstan-type  commit array{hash: string, message: string}
+ * @phpstan-type commit array{hash: string, message: string}
  */
 class DiffCollector
 {
diff --git a/src/External/Git.php b/src/External/Git.php
index c7b4089..61fb3f9 100644
--- a/src/External/Git.php
+++ b/src/External/Git.php
@@ -18,7 +18,7 @@ public function __construct()
     {
         $gitInstalled = $this->shellExec('which git');
         if (!$gitInstalled) {
-            throw new \RuntimeException('git command is not installed');
+            throw new \RuntimeException('the git command is not installed');
         }
     }