diff --git a/src/agents/orchestrator.py b/src/agents/orchestrator.py
index 6415ee6..f89930e 100644
--- a/src/agents/orchestrator.py
+++ b/src/agents/orchestrator.py
@@ -866,7 +866,7 @@ class AgentOrchestrator:
                 if analysis:
                     sources = analysis.get("sources", [])
                     sources_json = json.dumps(sources, ensure_ascii=False) if sources else None
-                    new_summary = analysis.get("summary", "")
+                    new_summary = analysis.get("summary", "") or previous_summary
 
                     await db.execute(
                         "UPDATE incidents SET summary = ?, sources_json = ?, updated_at = ? WHERE id = ?",