diff --git a/MinecraftClient.Tests/CSharpRunnerTests.cs b/MinecraftClient.Tests/CSharpRunnerTests.cs
new file mode 100644
index 00000000..c6846997
--- /dev/null
+++ b/MinecraftClient.Tests/CSharpRunnerTests.cs
@@ -0,0 +1,14 @@
+using MinecraftClient.Scripting;
+
+namespace MinecraftClient.Tests;
+
+public sealed class CSharpRunnerTests
+{
+    [Theory]
+    [InlineData("//using MinecraftClient.CommandHandler", "using MinecraftClient.CommandHandler;")]
+    [InlineData("//using MinecraftClient.CommandHandler;", "using MinecraftClient.CommandHandler;")]
+    public void NormalizeUsingDirectiveAddsMissingSemicolon(string directive, string expected)
+    {
+        Assert.Equal(expected, CSharpRunner.NormalizeUsingDirective(directive));
+    }
+}
diff --git a/MinecraftClient/Scripting/CSharpRunner.cs b/MinecraftClient/Scripting/CSharpRunner.cs
index 724ccb7f..880d6a39 100644
--- a/MinecraftClient/Scripting/CSharpRunner.cs
+++ b/MinecraftClient/Scripting/CSharpRunner.cs
@@ -60,7 +60,7 @@ namespace MinecraftClient.Scripting
                         string line = lines[i];
                         if (line.StartsWith("//using"))
                         {
-                            libs.Add(line.Replace("//", "").Trim());
+                            libs.Add(NormalizeUsingDirective(line));
                         }
                         else if (line.StartsWith("//dll"))
                         {
@@ -125,6 +125,12 @@ namespace MinecraftClient.Scripting
             else return null;
         }
 
+        internal static string NormalizeUsingDirective(string line)
+        {
+            string directive = line[2..].Trim();
+            return directive.EndsWith(';') ? directive : $"{directive};";
+        }
+
         private static string BuildScriptCode(string scriptName, IEnumerable<ScriptSourceLine> script, IEnumerable<ScriptSourceLine> extensions, IEnumerable<string> libs, bool hasImplicitReturn)
         {
             StringBuilder codeBuilder = new();