diff --git a/routes/chat.py b/routes/chat.py
index 4fc03e8..3f695a4 100644
--- a/routes/chat.py
+++ b/routes/chat.py
@@ -165,6 +165,9 @@ def _handle_openai_stream(
         for chunk in iter_openai_sse(resp):
             if chunk is None:
                 _dbg(f'流式响应结束，共 {chunk_count} 个数据片段')
+                close_chunk = think_extractor.finalize()
+                if close_chunk:
+                    yield sse_data_message(close_chunk)
                 yield sse_data_message('[DONE]')
                 return
 
diff --git a/routes/messages.py b/routes/messages.py
index e552683..0a010ec 100644
--- a/routes/messages.py
+++ b/routes/messages.py
@@ -93,9 +93,14 @@ def _inject_thinking(data):
 
 
 def _process_stream(resp):
-    """处理 /v1/messages 流式响应，检测并注入 thinking 事件"""
+    """处理 /v1/messages 流式响应，检测并注入 thinking 事件
+
+    追踪上游 content block 的 index，在注入 thinking blocks 时使用独立的 index，
+    并将后续上游 block 的 index 偏移，避免冲突。
+    """
     reasoning_buf = ''
     injected = False
+    index_offset = 0
 
     for line in resp.iter_lines():
         if not line:
@@ -119,7 +124,6 @@ def _process_stream(resp):
 
         modified = False
 
-        # 提取 reasoning_content
         for container_key in ('message', 'delta'):
             container = event_data.get(container_key)
             if not container:
@@ -129,13 +133,17 @@ def _process_stream(resp):
                 reasoning_buf += rc
                 modified = True
 
-        # 在首个 text_delta 前注入 thinking blocks
         if reasoning_buf and not injected:
             if event_data.get('delta', {}).get('type') == 'text_delta':
                 injected = True
                 yield from _emit_thinking_blocks(reasoning_buf)
+                index_offset = 1
                 reasoning_buf = ''
 
+        if index_offset and 'index' in event_data:
+            event_data['index'] = event_data['index'] + index_offset
+            modified = True
+
         yield f'data: {json.dumps(event_data)}\n\n' if modified else decoded + '\n\n'
 
 
diff --git a/settings.py b/settings.py
index 9580d21..58e657e 100644
--- a/settings.py
+++ b/settings.py
@@ -5,13 +5,13 @@
   - model_mappings: Cursor 模型名 → {upstream_model, backend, target_url, api_key, custom_instructions}
 """
 
+import copy
 import json
 import os
 import threading
 
 from config import Config
 
-# 数据目录放在项目根目录下，便于 Docker 卷挂载
 _ROOT_DIR = os.path.dirname(os.path.abspath(__file__))
 DATA_DIR = os.path.join(_ROOT_DIR, 'data')
 SETTINGS_FILE = os.path.join(DATA_DIR, 'settings.json')
@@ -38,10 +38,10 @@ def load():
                 with open(SETTINGS_FILE, 'r', encoding='utf-8') as f:
                     _cache = {**_DEFAULTS, **json.load(f)}
             except (json.JSONDecodeError, OSError):
-                _cache = dict(_DEFAULTS)
+                _cache = copy.deepcopy(_DEFAULTS)
         else:
-            _cache = dict(_DEFAULTS)
-    return dict(_cache)
+            _cache = copy.deepcopy(_DEFAULTS)
+    return copy.deepcopy(_cache)
 
 
 def save(data):
@@ -58,10 +58,13 @@ def save(data):
 
 
 def get():
-    """获取当前配置快照，优先返回内存缓存中的结果。"""
-    if _cache is None:
-        return load()
-    return dict(_cache)
+    """获取当前配置的深拷贝快照，保证调用方修改不影响缓存。"""
+    with _lock:
+        if _cache is None:
+            pass
+        else:
+            return copy.deepcopy(_cache)
+    return load()
 
 
 def get_url():
diff --git a/utils/http.py b/utils/http.py
index 3b5d8c2..c0f4506 100644
--- a/utils/http.py
+++ b/utils/http.py
@@ -126,10 +126,15 @@ def iter_responses_sse(response) -> Iterator[tuple[str, dict[str, Any]]]:
 
 
 def _iter_event_sse(response) -> Iterator[tuple[str, dict[str, Any]]]:
-    """解析带 event/data 的通用 SSE 流。"""
+    """解析带 event/data 的通用 SSE 流。
+
+    SSE 规范中空行是事件分隔符，遇到空行时重置 event_type，
+    避免前一个事件的类型泄漏到下一个事件。
+    """
     event_type = ''
     for line in response.iter_lines():
         if not line:
+            event_type = ''
             continue
         decoded = line.decode('utf-8', errors='replace')
         if decoded.startswith('event:'):
diff --git a/utils/think_tag.py b/utils/think_tag.py
index 269e7b6..2a783e0 100644
--- a/utils/think_tag.py
+++ b/utils/think_tag.py
@@ -30,24 +30,84 @@ class ThinkTagExtractor:
 
     处理跨 chunk 的 <think>...</think> 标签，将标签内的文本
     转为 reasoning_content delta，标签外的文本保持为 content delta。
+
+    额外处理：
+    - content 和 tool_calls 同时出现时拆分为两个独立 chunk（Cursor 会丢弃同时包含两者的 content）
+    - tool_calls 首次出现时在前面插入换行，确保文本以换行结束
+    - 流结束时如果 think 标签仍未关闭，自动合成关闭 chunk
     """
 
     def __init__(self):
         """初始化跨 chunk 的 thinking 状态跟踪。"""
         self._in_thinking = False
+        self._tool_calls_seen = False
 
     def process_chunk(self, chunk):
         """处理一个流式 chunk，返回转换后的 chunk 列表"""
         for choice in (chunk.get('choices') or []):
             delta = choice.get('delta') or {}
+
+            has_tool_calls = bool(delta.get('tool_calls'))
+            has_content = delta.get('content') is not None and delta.get('content') != ''
+
+            # content 和 tool_calls 同时出现：拆分为两个独立事件
+            if has_content and has_tool_calls:
+                results = []
+                content_chunk = self._make(chunk, content=delta['content'])
+                results.extend(self._process_content(content_chunk, delta['content']))
+                tc_chunk = {
+                    'id': chunk.get('id', ''),
+                    'object': 'chat.completion.chunk',
+                    'model': chunk.get('model', ''),
+                    'choices': [{'index': 0, 'delta': {'tool_calls': delta['tool_calls']},
+                                 'finish_reason': choice.get('finish_reason')}],
+                }
+                results.extend(self._handle_tool_calls_chunk(tc_chunk))
+                return results
+
+            if has_tool_calls:
+                return self._handle_tool_calls_chunk(chunk)
+
             if delta.get('reasoning_content'):
                 return [chunk]
             content = delta.get('content')
             if content is None or content == '':
                 return [chunk]
-            return self._split(chunk, content)
+            return self._process_content(chunk, content)
         return [chunk]
 
+    def finalize(self):
+        """流结束时调用，如果 think 标签仍未关闭则返回关闭 chunk"""
+        if not self._in_thinking:
+            return None
+        self._in_thinking = False
+        return {
+            'id': '',
+            'object': 'chat.completion.chunk',
+            'model': '',
+            'choices': [{'index': 0, 'delta': {'content': '\n</think>\n\n'}, 'finish_reason': None}],
+        }
+
+    def _process_content(self, chunk, content):
+        """处理包含 content 的 chunk"""
+        return self._split(chunk, content)
+
+    def _handle_tool_calls_chunk(self, chunk):
+        """处理包含 tool_calls 的 chunk，首次出现时在前面插入换行"""
+        results = []
+        if not self._tool_calls_seen:
+            self._tool_calls_seen = True
+            if self._in_thinking:
+                self._in_thinking = False
+                results.append(self._make(chunk, content='\n</think>\n\n'))
+            else:
+                results.append(self._make(chunk, content='\n'))
+        elif self._in_thinking:
+            self._in_thinking = False
+            results.append(self._make(chunk, content='\n</think>\n\n'))
+        results.append(chunk)
+        return results
+
     def _split(self, chunk, text):
         """根据 <think> 标签拆分文本为多个 chunk"""
         results = []