diff --git a/web/app/components/base/chat/chat/hooks.ts b/web/app/components/base/chat/chat/hooks.ts
index e8ce744236..4cde06ed2b 100644
--- a/web/app/components/base/chat/chat/hooks.ts
+++ b/web/app/components/base/chat/chat/hooks.ts
@@ -957,6 +957,7 @@ export const useChat = (
         })
       },
       onNodeStarted: ({ data: nodeStartedData }) => {
+        // `data` is the outer send payload for this request; loop child runs should not emit top-level node traces here.
         if (data.loop_id)
           return
 
@@ -977,6 +978,7 @@ export const useChat = (
         })
       },
       onNodeFinished: ({ data: nodeFinishedData }) => {
+        // Use the outer request payload here as well so loop child runs skip top-level finish handling entirely.
         if (data.loop_id)
           return
 
diff --git a/web/app/components/share/text-generation/result/index.tsx b/web/app/components/share/text-generation/result/index.tsx
index e3ffe9d209..a11e7436b5 100644
--- a/web/app/components/share/text-generation/result/index.tsx
+++ b/web/app/components/share/text-generation/result/index.tsx
@@ -337,7 +337,7 @@ const Result: FC<IResultProps> = ({
         onIterationFinish: ({ data }) => {
           setWorkflowProcessData(produce(getWorkflowProcessData()!, (draft) => {
             draft.expand = true
-            const iterationsIndex = draft.tracing.findIndex(item => item.id === data.id)!
+            const iterationsIndex = draft.tracing.findIndex(item => item.id === data.id)
             if (iterationsIndex > -1) {
               draft.tracing[iterationsIndex] = {
                 ...data,
@@ -367,7 +367,7 @@ const Result: FC<IResultProps> = ({
         onLoopFinish: ({ data }) => {
           setWorkflowProcessData(produce(getWorkflowProcessData()!, (draft) => {
             draft.expand = true
-            const loopsIndex = draft.tracing.findIndex(item => item.id === data.id)!
+            const loopsIndex = draft.tracing.findIndex(item => item.id === data.id)
             if (loopsIndex > -1) {
               draft.tracing[loopsIndex] = {
                 ...data,
diff --git a/web/app/components/workflow/utils/top-level-tracing.ts b/web/app/components/workflow/utils/top-level-tracing.ts
index 564812b105..30e0b5c8f6 100644
--- a/web/app/components/workflow/utils/top-level-tracing.ts
+++ b/web/app/components/workflow/utils/top-level-tracing.ts
@@ -15,6 +15,7 @@ export const upsertTopLevelTracingNodeOnStart = (
     ? tracing.findIndex(item => item.id === startedNode.id)
     : tracing.findIndex(item => item.node_id === startedNode.node_id)
   if (currentIndex > -1)
+    // Started events are the authoritative snapshot for an execution; merging would retain stale client-side fields.
     tracing[currentIndex] = startedNode
   else
     tracing.push(startedNode)