diff --git a/internal/workbenchruntime/service.go b/internal/workbenchruntime/service.go
index 892a8ca8..b0d53846 100644
--- a/internal/workbenchruntime/service.go
+++ b/internal/workbenchruntime/service.go
@@ -2072,7 +2072,7 @@ func latestTraceIDForSession(facts map[string][]any, sid string) string {
 
 func mergeFacts(sets ...map[string][]any) map[string][]any {
 	merged := emptyFacts()
-	keys := map[string]string{"sessions": "sessionId", "messages": "messageId", "parts": "partId", "turns": "turnId", "traceEvents": "id", "checkpoints": "traceId"}
+	keys := map[string]string{"sessions": "sessionId", "messageSummaries": "sessionId", "messages": "messageId", "parts": "partId", "turns": "turnId", "traceEvents": "id", "checkpoints": "traceId"}
 	for _, set := range sets {
 		for family, idKey := range keys {
 			seen := map[string]bool{}