diff --git a/.memory/worklog.json b/.memory/worklog.json
index 97e0bba..0ead733 100644
--- a/.memory/worklog.json
+++ b/.memory/worklog.json
@@ -542,6 +542,13 @@
       "type": "session-heartbeat",
       "message": "Codex 会话活跃 · 最近命令：codex · 分支 master · 6 项未提交变更 · 最近提交：auto-save 2026-05-19 11:13 (~2)",
       "files_changed": 6
+    },
+    {
+      "ts": "2026-05-19T11:31:13+08:00",
+      "type": "commit",
+      "message": "auto-save 2026-05-19 11:29 (~6)",
+      "hash": "65a9080",
+      "files_changed": 6
     }
   ]
 }
diff --git a/src/app/api/packs/generate/route.ts b/src/app/api/packs/generate/route.ts
index ee588d7..6592e67 100644
--- a/src/app/api/packs/generate/route.ts
+++ b/src/app/api/packs/generate/route.ts
@@ -33,23 +33,25 @@ export async function POST(req: Request) {
     return NextResponse.json({ error: 'image must be selected before generating packs' }, { status: 400 });
   }
 
+  const baseSession = session;
+  const baseSourceImage = sourceImage;
   async function run() {
     const { pack, manifest, provider } = await generateAssetPack({
-      session,
-      sourceImage,
+      session: baseSession,
+      sourceImage: baseSourceImage,
       kind,
-      onProgress: progressPack => persistPackProgress(session, imageId, progressPack),
+      onProgress: progressPack => persistPackProgress(baseSession, imageId, progressPack),
     });
-    session.characterSpec = pack.characterSpec;
-    session.packs = [
-      ...(session.packs ?? []).filter(existing => !(existing.kind === kind && existing.sourceImageId === imageId)),
+    baseSession.characterSpec = pack.characterSpec;
+    baseSession.packs = [
+      ...(baseSession.packs ?? []).filter(existing => !(existing.kind === kind && existing.sourceImageId === imageId)),
       pack,
     ];
-    session.exports = [
-      ...(session.exports ?? []).filter(existing => !(existing.packKind === kind && existing.source.sourceImageId === imageId)),
+    baseSession.exports = [
+      ...(baseSession.exports ?? []).filter(existing => !(existing.packKind === kind && existing.source.sourceImageId === imageId)),
       manifest,
     ];
-    await saveSession(session);
+    await saveSession(baseSession);
     return { pack, manifest, provider } satisfies GeneratePackResponse;
   }