diff --git a/conf/llm_factories.json b/conf/llm_factories.json
index 71f47be2e..90602c65f 100644
--- a/conf/llm_factories.json
+++ b/conf/llm_factories.json
@@ -7,6 +7,20 @@
             "status": "1",
             "rank": "999",
             "llm": [
+                {
+                    "llm_name": "gpt-5.1",
+                    "tags": "LLM,CHAT,400k,IMAGE2TEXT",
+                    "max_tokens": 400000,
+                    "model_type": "chat",
+                    "is_tools": true
+                },
+                {
+                    "llm_name": "gpt-5.1-chat-latest",
+                    "tags": "LLM,CHAT,400k,IMAGE2TEXT",
+                    "max_tokens": 400000,
+                    "model_type": "chat",
+                    "is_tools": true
+                },
                 {
                     "llm_name": "gpt-5",
                     "tags": "LLM,CHAT,400k,IMAGE2TEXT",
@@ -3218,6 +3232,13 @@
             "status": "1",
             "rank": "990",
             "llm": [
+                {
+                    "llm_name": "claude-opus-4-5-20251101",
+                    "tags": "LLM,CHAT,IMAGE2TEXT,200k",
+                    "max_tokens": 204800,
+                    "model_type": "chat",
+                    "is_tools": true
+                },
                 {
                     "llm_name": "claude-opus-4-1-20250805",
                     "tags": "LLM,CHAT,IMAGE2TEXT,200k",
diff --git a/rag/llm/chat_model.py b/rag/llm/chat_model.py
index cce5b2454..9fbc88348 100644
--- a/rag/llm/chat_model.py
+++ b/rag/llm/chat_model.py
@@ -132,6 +132,11 @@ class Base(ABC):
 
         gen_conf = {k: v for k, v in gen_conf.items() if k in allowed_conf}
 
+        model_name_lower = (self.model_name or "").lower()
+        # gpt-5 and gpt-5.1 endpoints have inconsistent parameter support, clear custom generation params to prevent unexpected issues
+        if "gpt-5" in model_name_lower:
+            gen_conf = {}
+
         return gen_conf
 
     def _chat(self, history, gen_conf, **kwargs):