diff --git a/state_machine_exporter/src/test/java/click/kamil/springstatemachineexporter/exporter/PlantUmlTest.java b/state_machine_exporter/src/test/java/click/kamil/springstatemachineexporter/exporter/PlantUmlTest.java
new file mode 100644
index 0000000..a155213
--- /dev/null
+++ b/state_machine_exporter/src/test/java/click/kamil/springstatemachineexporter/exporter/PlantUmlTest.java
@@ -0,0 +1,55 @@
+package click.kamil.springstatemachineexporter.exporter;
+
+import click.kamil.springstatemachineexporter.model.State;
+import click.kamil.springstatemachineexporter.model.Transition;
+import click.kamil.springstatemachineexporter.model.TransitionType;
+import click.kamil.springstatemachineexporter.model.Guard;
+import click.kamil.springstatemachineexporter.model.Action;
+import org.junit.jupiter.api.Test;
+
+import java.util.List;
+import java.util.Set;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class PlantUmlTest {
+
+    @Test
+    void testExportSanitizesLabels() {
+        PlantUml plantUml = new PlantUml();
+        ExportOptions options = ExportOptions.builder()
+                .embedIdentifiers(true)
+                .useLambdaGuards(false)
+                .build();
+
+        State state1 = State.of("State1");
+        State state2 = State.of("State2");
+
+        Transition t = new Transition();
+        t.setType(TransitionType.EXTERNAL);
+        t.setSourceStates(List.of(state1));
+        t.setTargetStates(List.of(state2));
+        
+        // Add a guard and action containing problematic characters
+        t.setGuard(Guard.of("list.size() < 5", false, null, null, null, null));
+        t.setActions(List.of(Action.of("doSomething(new int[]{1, 2})", false, null, null, null, null)));
+
+        String result = plantUml.export(
+                "TestMachine",
+                List.of(t),
+                Set.of("State1"),
+                Set.of("State2"),
+                options
+        );
+
+        // Verify that < and > are replaced with HTML entities
+        assertThat(result).doesNotContain("< 5");
+        assertThat(result).contains("&lt; 5");
+
+        // Verify that [ and ] are replaced with HTML entities inside the link
+        assertThat(result).doesNotContain("[list.size() &lt; 5]");
+        assertThat(result).doesNotContain("new int[]{1, 2}");
+        assertThat(result).contains("&#91;list.size() &lt; 5&#93;");
+        assertThat(result).contains("new int&#91;&#93;{1, 2}");
+    }
+}