diff --git a/contributing/samples/gepa/rater_lib.py b/contributing/samples/gepa/rater_lib.py
index 50bbdc229d..67c46da71c 100644
--- a/contributing/samples/gepa/rater_lib.py
+++ b/contributing/samples/gepa/rater_lib.py
@@ -167,7 +167,7 @@ def __call__(self, messages: list[dict[str, Any]]) -> dict[str, Any]:
     Returns:
       A dictionary containing rating information including score.
     """
-    env = jinja2.Environment()
+    env = jinja2.Environment(autoescape=True)
     env.globals['user_input'] = (
         messages[0].get('parts', [{}])[0].get('text', '') if messages else ''
     )
diff --git a/contributing/samples/gepa/rubric_validation_template.txt b/contributing/samples/gepa/rubric_validation_template.txt
index eeab5af849..74db111ab0 100644
--- a/contributing/samples/gepa/rubric_validation_template.txt
+++ b/contributing/samples/gepa/rubric_validation_template.txt
@@ -155,12 +155,12 @@ Verdict: no
   </available_tools>
 
   <main_prompt>
-  {{user_input}}
+  {{user_input|e}}
   </main_prompt>
 </user_prompt>
 
 <responses>
-{{model_response}}
+{{model_response|e}}
 </responses>
 
 <properties>