From c2bf7116051d8aa5d0d3b4d40618d512d7d4d150 Mon Sep 17 00:00:00 2001
From: Michael Staib <michael@chillicream.com>
Date: Tue, 21 Apr 2026 07:43:37 +0000
Subject: [PATCH] Fix variable validation

---
 .../Core/src/Validation/Rules/VariableVisitor.cs   |  4 +++-
 .../Validation.Tests/NoUnusedVariablesRuleTests.cs | 14 ++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/src/HotChocolate/Core/src/Validation/Rules/VariableVisitor.cs b/src/HotChocolate/Core/src/Validation/Rules/VariableVisitor.cs
index f35023700ca..126fbd31a63 100644
--- a/src/HotChocolate/Core/src/Validation/Rules/VariableVisitor.cs
+++ b/src/HotChocolate/Core/src/Validation/Rules/VariableVisitor.cs
@@ -122,7 +122,9 @@ protected override ISyntaxVisitorAction Enter(
     {
         if (IntrospectionFields.TypeName.EqualsOrdinal(node.Name.Value))
         {
-            return Skip;
+            context.OutputFields.Push(TypeNameField);
+            context.Types.Push(TypeNameField.Type);
+            return Continue;
         }
 
         if (context.Types.TryPeek(out var type) &&
diff --git a/src/HotChocolate/Core/test/Validation.Tests/NoUnusedVariablesRuleTests.cs b/src/HotChocolate/Core/test/Validation.Tests/NoUnusedVariablesRuleTests.cs
index f54b9f96f68..de6fa52f28d 100644
--- a/src/HotChocolate/Core/test/Validation.Tests/NoUnusedVariablesRuleTests.cs
+++ b/src/HotChocolate/Core/test/Validation.Tests/NoUnusedVariablesRuleTests.cs
@@ -109,6 +109,20 @@ fragment FragA on Query {
             ");
     }
 
+    [Fact]
+    public void VariableUsedByIncludeDirectiveInFragment()
+    {
+        ExpectValid(
+            """
+            query Q($v: Boolean!) {
+              ...F
+            }
+            fragment F on Query {
+              __typename @include(if: $v)
+            }
+            """);
+    }
+
     [Fact]
     public void MultipleVariablesNotUsed()
     {