diff --git a/desktop_env/desktop_env.py b/desktop_env/desktop_env.py
index daba009..f0ffafe 100644
--- a/desktop_env/desktop_env.py
+++ b/desktop_env/desktop_env.py
@@ -474,13 +474,18 @@ class DesktopEnv(gym.Env):
             if "expected" in self.evaluator:
                 assert len(self.metric) == len(self.expected_getter), "The number of metrics and expected getters must be the same"
             for idx, metric in enumerate(self.metric):
-                try:
-                    config = self.evaluator["result"][idx]
-                    result_state = self.result_getter[idx](self, config)
-                except FileNotFoundError:
-                    logger.error("File not found!")
-                    if self.metric_conj == 'and':
-                        return 0
+                # Skip result state extraction if result_getter is None (e.g., for vllm_eval)
+                if self.result_getter[idx] is not None:
+                    try:
+                        config = self.evaluator["result"][idx]
+                        result_state = self.result_getter[idx](self, config)
+                    except FileNotFoundError:
+                        logger.error("File not found!")
+                        if self.metric_conj == 'and':
+                            return 0
+                else:
+                    # For evaluators that don't need result state (e.g., vllm_eval)
+                    result_state = None
 
                 if "expected" in self.evaluator and self.expected_getter and self.evaluator["expected"]:
                     expected_state = self.expected_getter[idx](self, self.evaluator["expected"][idx])
@@ -498,11 +503,16 @@ class DesktopEnv(gym.Env):
             return sum(results) / len(results) if self.metric_conj == 'and' else max(results)
         else:
             # Single metric to evaluate whether the task is successfully completed
-            try:
-                result_state = self.result_getter(self, self.evaluator["result"])
-            except FileNotFoundError:
-                logger.error("File not found!")
-                return 0
+            # For evaluators like vllm_eval that don't need result_getter, skip result state extraction
+            if self.result_getter is not None:
+                try:
+                    result_state = self.result_getter(self, self.evaluator["result"])
+                except FileNotFoundError:
+                    logger.error("File not found!")
+                    return 0
+            else:
+                # For evaluators that don't need result state (e.g., vllm_eval)
+                result_state = None
 
             if "expected" in self.evaluator and self.expected_getter and self.evaluator["expected"]:
                 expected_state = self.expected_getter(self, self.evaluator["expected"])