diff --git a/core/main_terminal_parts/tools_definition/file_tools.py b/core/main_terminal_parts/tools_definition/file_tools.py
index 62ea7b81..a2664859 100644
--- a/core/main_terminal_parts/tools_definition/file_tools.py
+++ b/core/main_terminal_parts/tools_definition/file_tools.py
@@ -247,7 +247,7 @@ class ToolsDefinitionFileToolsMixin:
                                             "properties": {
                                                 "old_string": {
                                                     "type": "string",
-                                                    "description": "要替换的文本（需与文件内容精确匹配，保留缩进；建议提供至少3行提升定位稳定性。需要批量替换的场景可以单行或不足一行）"
+                                                    "description": "要替换的文本（需与文件内容精确匹配，保留缩进；必须提供至少3行内容，包含目标行及其前后上下文，不足3行将被拒绝执行）"
                                                 },
                                                 "new_string": {
                                                     "type": "string",
diff --git a/modules/file_manager/replace_mixin.py b/modules/file_manager/replace_mixin.py
index e59c070f..2d25b500 100644
--- a/modules/file_manager/replace_mixin.py
+++ b/modules/file_manager/replace_mixin.py
@@ -73,7 +73,12 @@ class ReplaceMixin:
                 "error": tr("file_manager.replace_new_text_too_long"),
                 "suggestion": "请将大内容分成多个小的替换操作"
             }
-        short_old_text_notice = bool(old_text and len(old_text.splitlines()) < 3)
+        if old_text and len(old_text.splitlines()) < 3:
+            return {
+                "success": False,
+                "error": tr("file_manager.replace_old_text_too_short"),
+                "suggestion": "请在 old_string 中包含目标行及其前后上下文（至少3行）后重试"
+            }
 
         # 检查是否包含要替换的内容
         if old_text and old_text not in content:
@@ -111,11 +116,6 @@ class ReplaceMixin:
                         lines=line_text,
                         count=count,
                     ))
-            if short_old_text_notice:
-                message_parts.insert(
-                    0,
-                    tr("file_manager.replace_short_old_notice")
-                )
             if message_parts:
                 result["message"] = "；".join(message_parts)
             print(f"{OUTPUT_FORMATS['file']} 替换了 {count} 处内容")
@@ -144,7 +144,6 @@ class ReplaceMixin:
         failed_details: List[Dict[str, Any]] = []
         total_replacements = 0
         total_found_matches = 0
-        short_old_text_indices: List[int] = []
 
         for zero_based_index, item in enumerate(replacements):
             index = zero_based_index + 1
@@ -230,7 +229,13 @@ class ReplaceMixin:
                 break
 
             if len(old_text.splitlines()) < 3:
-                short_old_text_indices.append(index)
+                detail.update({
+                    "status": "error",
+                    "reason": "old_string 少于3行，请包含目标行及其前后上下文（至少3行）后重试"
+                })
+                failed_details.append(detail.copy())
+                details.append(detail)
+                break
 
             matched_lines = self._find_match_line_numbers(current_content, old_text)
             found_count = len(matched_lines)
@@ -300,9 +305,6 @@ class ReplaceMixin:
                 groups=len(replacements),
                 replacements=total_replacements,
             )]
-            if short_old_text_indices:
-                indices_text = ",".join(str(item) for item in short_old_text_indices)
-                message_parts.append(tr("file_manager.replace_many_short_notice", indices=indices_text))
             write_result["message"] = "；".join(message_parts)
             print(f"{OUTPUT_FORMATS['file']} 批量替换了 {total_replacements} 处内容")
         return write_result
diff --git a/modules/i18n_messages/file_manager.py b/modules/i18n_messages/file_manager.py
index 1d2cf15c..bb6e29db 100644
--- a/modules/i18n_messages/file_manager.py
+++ b/modules/i18n_messages/file_manager.py
@@ -258,16 +258,12 @@ MESSAGES = {
         "zh-CN": "发现{found}处，于{lines}行共替换{count}处",
         "en-US": "Found {found} matches; replaced {count} at lines {lines}",
     },
-    "file_manager.replace_short_old_notice": {
-        "zh-CN": "提示：old_string 少于3行，已继续执行；需要批量替换的场景可以单行或不足一行",
-        "en-US": "Note: old_string is shorter than 3 lines; execution continued. For batch replacement, use single-line or shorter strings",
+    "file_manager.replace_old_text_too_short": {
+        "zh-CN": "old_string 少于3行：为确保精确匹配，请提供至少3行内容（包含目标行及其前后上下文）",
+        "en-US": "old_string has fewer than 3 lines: to ensure precise matching, provide at least 3 lines including the target line and its surrounding context",
     },
     "file_manager.replace_many_summary": {
         "zh-CN": "共 {groups} 组替换，替换 {replacements} 处",
         "en-US": "{groups} groups processed; {replacements} replacements made",
     },
-    "file_manager.replace_many_short_notice": {
-        "zh-CN": "提示：第 {indices} 组 old_string 少于3行，已继续执行",
-        "en-US": "Note: old_string in groups {indices} is shorter than 3 lines; execution continued",
-    },
 }
\ No newline at end of file