diff --git a/astrbot/core/pipeline/process_stage/method/agent_sub_stages/internal.py b/astrbot/core/pipeline/process_stage/method/agent_sub_stages/internal.py
index 9c1c1c9a9..984b8f9bf 100644
--- a/astrbot/core/pipeline/process_stage/method/agent_sub_stages/internal.py
+++ b/astrbot/core/pipeline/process_stage/method/agent_sub_stages/internal.py
@@ -76,6 +76,8 @@ class InternalAgentSubStage(Stage):
             max(1, settings["dequeue_context_length"]),
             self.max_context_length - 1,
         )
+        if self.dequeue_context_length <= 0:
+            self.dequeue_context_length = 1
 
         self.conv_manager = ctx.plugin_manager.context.conversation_manager