diff --git a/agentplatform/_genai/_evals_visualization.py b/agentplatform/_genai/_evals_visualization.py
index dc0ab0e7a1..b40a614b61 100644
--- a/agentplatform/_genai/_evals_visualization.py
+++ b/agentplatform/_genai/_evals_visualization.py
@@ -359,6 +359,10 @@ def get_evaluation_html(eval_result_json: str) -> str:
         <div id="details-section"></div>
     </div>
     <script>
+        // Render single newlines as <br> so streaming model output and
+        // poem/code formatting is preserved in the HTML display.
+        marked.setOptions({{ breaks: true }});
+
         var vizData_vertex_eval_sdk = JSON.parse(new TextDecoder().decode(Uint8Array.from(atob("{payload_b64}"), c => c.charCodeAt(0))));
 
         function formatDictVals(obj) {{
@@ -929,6 +933,10 @@ def get_comparison_html(eval_result_json: str) -> str:
         <div id="details-section"></div>
     </div>
     <script>
+        // Render single newlines as <br> so streaming model output and
+        // poem/code formatting is preserved in the HTML display.
+        marked.setOptions({{ breaks: true }});
+
         var vizData_vertex_eval_sdk = JSON.parse(new TextDecoder().decode(Uint8Array.from(atob("{payload_b64}"), c => c.charCodeAt(0))));
 
         function formatToolDeclarations(toolDeclarations) {{
@@ -1371,6 +1379,10 @@ def get_inference_html(dataframe_json: str) -> str:
         <div id="results-table"></div>
     </div>
     <script>
+        // Render single newlines as <br> so streaming model output and
+        // poem/code formatting is preserved in the HTML display.
+        marked.setOptions({{ breaks: true }});
+
         var vizData_vertex_eval_sdk = JSON.parse(new TextDecoder().decode(Uint8Array.from(atob("{payload_b64}"), c => c.charCodeAt(0))));
         var container_vertex_eval_sdk = document.getElementById('results-table');