diff --git a/openapi.go b/openapi.go
index 816c55e..fe7210f 100644
--- a/openapi.go
+++ b/openapi.go
@@ -681,7 +681,7 @@ func graphqlRequestSchema() map[string]any {
 }
 
 func graphqlResponses() map[string]any {
-	successHeaders := mergeHeaders(standardResponseHeaders(), rateLimitSuccessHeaders())
+	successHeaders := mergeHeaders(standardResponseHeaders(), rateLimitSuccessHeaders(), cacheSuccessHeaders())
 	errorHeaders := mergeHeaders(standardResponseHeaders(), rateLimitSuccessHeaders())
 
 	return map[string]any{
diff --git a/openapi_test.go b/openapi_test.go
index 3fc70fd..1344279 100644
--- a/openapi_test.go
+++ b/openapi_test.go
@@ -247,6 +247,12 @@ func TestSpecBuilder_Good_GraphQLEndpoint(t *testing.T) {
 		t.Fatalf("expected GraphQL operationId to be post_graphql, got %v", postOp["operationId"])
 	}
 
+	responses := postOp["responses"].(map[string]any)
+	successHeaders := responses["200"].(map[string]any)["headers"].(map[string]any)
+	if _, ok := successHeaders["X-Cache"]; !ok {
+		t.Fatal("expected X-Cache header on GraphQL 200 response")
+	}
+
 	requestBody := postOp["requestBody"].(map[string]any)
 	schema := requestBody["content"].(map[string]any)["application/json"].(map[string]any)["schema"].(map[string]any)
 	properties := schema["properties"].(map[string]any)