diff --git a/core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/AiServicesProcessor.java b/core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/AiServicesProcessor.java
index 26240583e..f171adc34 100644
--- a/core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/AiServicesProcessor.java
+++ b/core/deployment/src/main/java/io/quarkiverse/langchain4j/deployment/AiServicesProcessor.java
@@ -560,7 +560,7 @@ private List<TemplateParameterInfo> gatherTemplateParamInfo(List<MethodParameter
 
         List<TemplateParameterInfo> templateParams = new ArrayList<>();
         for (MethodParameterInfo param : params) {
-            if (param.annotations().isEmpty()) { // if a parameter has no annotations it is considered a template variable
+            if (effectiveParamAnnotations(param).isEmpty()) { // if a parameter has no annotations it is considered a template variable
                 templateParams.add(new TemplateParameterInfo(param.position(), param.name()));
             } else {
                 AnnotationInstance vInstance = param.annotation(V);
@@ -581,6 +581,19 @@ private List<TemplateParameterInfo> gatherTemplateParamInfo(List<MethodParameter
         return templateParams;
     }
 
+    private List<AnnotationInstance> effectiveParamAnnotations(MethodParameterInfo param) {
+        return param.annotations().stream().filter(ai -> {
+            String name = ai.name().toString();
+            if (name.startsWith("kotlin")) {
+                return false;
+            }
+            if (name.endsWith("NotNull")) {
+                return false;
+            }
+            return true;
+        }).collect(Collectors.toList());
+    }
+
     private Optional<AiServiceMethodCreateInfo.TemplateInfo> gatherSystemMessageInfo(MethodInfo method,
             List<TemplateParameterInfo> templateParams) {
         AnnotationInstance instance = method.annotation(Langchain4jDotNames.SYSTEM_MESSAGE);
diff --git a/openai/openai-vanilla/deployment/src/test/java/org/acme/examples/aiservices/AiServicesTest.java b/openai/openai-vanilla/deployment/src/test/java/org/acme/examples/aiservices/AiServicesTest.java
index be05454a4..48d8600a3 100644
--- a/openai/openai-vanilla/deployment/src/test/java/org/acme/examples/aiservices/AiServicesTest.java
+++ b/openai/openai-vanilla/deployment/src/test/java/org/acme/examples/aiservices/AiServicesTest.java
@@ -14,6 +14,7 @@
 import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.assertj.core.api.Assertions.tuple;
 
+import jakarta.validation.constraints.NotNull;
 import java.io.IOException;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
@@ -121,7 +122,7 @@ public void test_simple_instruction_with_single_argument_and_no_annotations() th
     interface Humorist {
 
         @UserMessage("Tell me a joke about {{it}}")
-        String joke(String topic);
+        String joke(@NotNull String topic);
     }
 
     @Test