diff --git a/data/chroma/kb_1/add53ead-7f8c-45e1-9851-b11e93ad0dfb/data_level0.bin b/data/chroma/kb_1/add53ead-7f8c-45e1-9851-b11e93ad0dfb/data_level0.bin
index 7de8488..d878af2 100644
Binary files a/data/chroma/kb_1/add53ead-7f8c-45e1-9851-b11e93ad0dfb/data_level0.bin and b/data/chroma/kb_1/add53ead-7f8c-45e1-9851-b11e93ad0dfb/data_level0.bin differ
diff --git a/data/chroma/kb_1/chroma.sqlite3 b/data/chroma/kb_1/chroma.sqlite3
index 5d385b4..8bac5d5 100644
Binary files a/data/chroma/kb_1/chroma.sqlite3 and b/data/chroma/kb_1/chroma.sqlite3 differ
diff --git a/th_agenter/api/endpoints/agent_chat.py b/th_agenter/api/endpoints/agent_chat.py
index 3d14beb..6433cad 100644
--- a/th_agenter/api/endpoints/agent_chat.py
+++ b/th_agenter/api/endpoints/agent_chat.py
@@ -89,7 +89,7 @@ async def agent_chat(
         results = all_results[: body.top_k]
         max_score = _score(results[0]) if results else 0.0
 
-        if results and max_score >= 0.5:
+        if results and max_score >= 0.45:
             knowledge_base_used = True
             first_kb_id_used = kb_ids[0]
             refs = []
@@ -243,7 +243,7 @@ async def agent_chat_stream(
         results = all_results[: body.top_k]
         max_score = _score(results[0]) if results else 0.0
 
-        if results and max_score >= 0.5:
+        if results and max_score >= 0.45:
             knowledge_base_used = True
             refs = []
             for i, r in enumerate(results[:5], 1):
diff --git a/th_agenter/services/workflow_engine.py b/th_agenter/services/workflow_engine.py
index 5ec6d43..56b4f7c 100644
--- a/th_agenter/services/workflow_engine.py
+++ b/th_agenter/services/workflow_engine.py
@@ -730,7 +730,7 @@ class WorkflowEngine:
                     if score > max_score:
                         max_score = score
 
-                is_relevant = max_score >= 0.5
+                is_relevant = max_score >= 0.45
 
                 if is_relevant:
                     # 有相关的知识库结果，构建 RAG 风格的提示词
@@ -1310,7 +1310,7 @@ class WorkflowEngine:
         
         query = config.get('query', '')
         top_k = config.get('top_k', config.get('topK', 5))
-        similarity_threshold = config.get('similarity_threshold', config.get('similarityThreshold', 0.7))
+        similarity_threshold = config.get('similarity_threshold', config.get('similarityThreshold', 0.45))
         
         # 如果还是没有，尝试从节点名称中提取（例如 "knowledge-base 2" -> 2）
         if not knowledge_base_id: