From 651c1a28b894dacfa90387f1e824535bab0686c7 Mon Sep 17 00:00:00 2001
From: Sandy Tao <sandytao520@icloud.com>
Date: Fri, 6 Mar 2026 18:33:43 -0800
Subject: [PATCH] perf: skip file I/O in updateMessagesFromHistory when no tool
 calls match

Build the partsMap before touching the conversation file. If no
function responses are found in the history, return immediately
without reading or writing the session JSON.
---
 .../core/src/services/chatRecordingService.ts | 47 +++++++++----------
 1 file changed, 22 insertions(+), 25 deletions(-)

diff --git a/packages/core/src/services/chatRecordingService.ts b/packages/core/src/services/chatRecordingService.ts
index 64d7056b6d..eb2b0b295e 100644
--- a/packages/core/src/services/chatRecordingService.ts
+++ b/packages/core/src/services/chatRecordingService.ts
@@ -694,37 +694,34 @@ export class ChatRecordingService {
     if (!this.conversationFile) return;
 
     try {
-      this.updateConversation((conversation) => {
-        // Create a map of tool results from the API history for quick lookup by call ID.
-        // We store the full list of parts associated with each tool call ID to preserve
-        // multi-modal data and proper trajectory structure.
-        const partsMap = new Map<string, Part[]>();
-        for (const content of history) {
-          if (content.role === 'user' && content.parts) {
-            // Find all unique call IDs in this message
-            const callIds = content.parts
-              .map((p) => p.functionResponse?.id)
-              .filter((id): id is string => !!id);
+      // Build the parts map from the API history BEFORE touching the file.
+      const partsMap = new Map<string, Part[]>();
+      for (const content of history) {
+        if (content.role === 'user' && content.parts) {
+          const callIds = content.parts
+            .map((p) => p.functionResponse?.id)
+            .filter((id): id is string => !!id);
 
-            if (callIds.length === 0) continue;
+          if (callIds.length === 0) continue;
 
-            // Use the first ID as a seed to capture any "leading" non-ID parts
-            // in this specific content block.
-            let currentCallId = callIds[0];
-            for (const part of content.parts) {
-              if (part.functionResponse?.id) {
-                currentCallId = part.functionResponse.id;
-              }
-
-              if (!partsMap.has(currentCallId)) {
-                partsMap.set(currentCallId, []);
-              }
-              partsMap.get(currentCallId)!.push(part);
+          let currentCallId = callIds[0];
+          for (const part of content.parts) {
+            if (part.functionResponse?.id) {
+              currentCallId = part.functionResponse.id;
             }
+
+            if (!partsMap.has(currentCallId)) {
+              partsMap.set(currentCallId, []);
+            }
+            partsMap.get(currentCallId)!.push(part);
           }
         }
+      }
 
-        // Update the conversation records tool results if they've changed.
+      // Nothing to sync — skip the read/write entirely.
+      if (partsMap.size === 0) return;
+
+      this.updateConversation((conversation) => {
         for (const message of conversation.messages) {
           if (message.type === 'gemini' && message.toolCalls) {
             for (const toolCall of message.toolCalls) {