diff --git a/apps/worker/worker_app/tasks/vision/vlm_fallback.py b/apps/worker/worker_app/tasks/vision/vlm_fallback.py
index c9b9e1d61..eef12b395 100644
--- a/apps/worker/worker_app/tasks/vision/vlm_fallback.py
+++ b/apps/worker/worker_app/tasks/vision/vlm_fallback.py
@@ -140,11 +140,11 @@ def call_pro_vlm(
             usage.get("completion_tokens", 0),
         )
         text = _strip_code_fence(raw)
-        l, r_pos = text.find("{"), text.rfind("}")
-        if l < 0 or r_pos <= l:
+        lpos, r_pos = text.find("{"), text.rfind("}")
+        if lpos < 0 or r_pos <= lpos:
             logger.warning("[vision.v2] pro 无JSON elapsed=%.1fs head=%s", elapsed, raw[:200])
             return None
-        obj = json.loads(text[l : r_pos + 1])
+        obj = json.loads(text[lpos : r_pos + 1])
         if not isinstance(obj, dict):
             return None
         scene = obj.get("scene") or "通用"
diff --git a/apps/worker/worker_app/tasks/vision/vlm_fast_json.py b/apps/worker/worker_app/tasks/vision/vlm_fast_json.py
index 3de9bba1b..48af71262 100644
--- a/apps/worker/worker_app/tasks/vision/vlm_fast_json.py
+++ b/apps/worker/worker_app/tasks/vision/vlm_fast_json.py
@@ -152,9 +152,9 @@ def call_fast_json(
             reasoning_tokens,
         )
         text = _strip_code_fence(raw)
-        l, r = text.find("{"), text.rfind("}")
-        if l >= 0 and r > l:
-            text = text[l : r + 1]
+        lpos, r = text.find("{"), text.rfind("}")
+        if lpos >= 0 and r > lpos:
+            text = text[lpos : r + 1]
         try:
             obj = json.loads(text)
         except json.JSONDecodeError: