666ghj · Pratiyankkumar · Mar 10, 2026 · Mar 10, 2026 · Mar 10, 2026
diff --git a/backend/app/api/graph.py b/backend/app/api/graph.py
@@ -10,6 +10,7 @@
 
 from . import graph_bp
 from ..config import Config
+from ..utils.request_locale import get_request_locale
 from ..services.ontology_generator import OntologyGenerator
 from ..services.graph_builder import GraphBuilderService
 from ..services.text_processor import TextProcessor
@@ -211,13 +212,15 @@ def generate_ontology():
         ProjectManager.save_extracted_text(project.project_id, all_text)
         logger.info(f"文本提取完成，共 {len(all_text)} 字符")
 
-        # 生成本体
-        logger.info("调用 LLM 生成本体定义...")
+        # 生成本体（传递用户语言，LLM 输出与该语言一致）
+        locale = get_request_locale()
+        logger.info(f"调用 LLM 生成本体定义... (locale={locale})")
         generator = OntologyGenerator()
         ontology = generator.generate(
             document_texts=document_texts,
             simulation_requirement=simulation_requirement,
-            additional_context=additional_context if additional_context else None
+            additional_context=additional_context if additional_context else None,
+            language=locale
         )
 
         # 保存本体到项目

diff --git a/backend/app/api/report.py b/backend/app/api/report.py
@@ -10,6 +10,8 @@
 
 from . import report_bp
 from ..config import Config
+from ..utils.request_locale import get_request_locale
+from ..utils.error_messages import get_error_message
 from ..services.report_agent import ReportAgent, ReportManager, ReportStatus
 from ..services.simulation_manager import SimulationManager
 from ..models.project import ProjectManager
@@ -105,6 +107,9 @@ def generate_report():
                 "error": "缺少模拟需求描述"
             }), 400
 
+        # 获取用户语言偏好（在启动线程前捕获，线程内 request 可能不可用）
+        report_language = get_request_locale()
+
         # 提前生成 report_id，以便立即返回给前端
         import uuid
         report_id = f"report_{uuid.uuid4().hex[:12]}"
@@ -130,11 +135,12 @@ def run_generate():
                     message="初始化Report Agent..."
                 )
 
-                # 创建Report Agent
+                # 创建Report Agent（传入用户语言，报告和对话均使用该语言）
                 agent = ReportAgent(
                     graph_id=graph_id,
                     simulation_id=simulation_id,
-                    simulation_requirement=simulation_requirement
+                    simulation_requirement=simulation_requirement,
+                    report_language=report_language
                 )
 
                 # 进度回调
@@ -498,16 +504,17 @@ def chat_with_report_agent():
         message = data.get('message')
         chat_history = data.get('chat_history', [])
 
+        report_lang = get_request_locale()
         if not simulation_id:
             return jsonify({
                 "success": False,
-                "error": "请提供 simulation_id"
+                "error": get_error_message('missing_simulation_id', report_lang)
             }), 400
-        
+
         if not message:
             return jsonify({
                 "success": False,
-                "error": "请提供 message"
+                "error": get_error_message('missing_message', report_lang)
             }), 400
 
         # 获取模拟和项目信息
@@ -517,30 +524,32 @@ def chat_with_report_agent():
         if not state:
             return jsonify({
                 "success": False,
-                "error": f"模拟不存在: {simulation_id}"
+                "error": f"{get_error_message('simulation_not_found', report_lang)}: {simulation_id}"
             }), 404
-        
+
         project = ProjectManager.get_project(state.project_id)
         if not project:
             return jsonify({
                 "success": False,
-                "error": f"项目不存在: {state.project_id}"
+                "error": f"{get_error_message('project_not_found', report_lang)}: {state.project_id}"
             }), 404
-        
+
         graph_id = state.graph_id or project.graph_id
         if not graph_id:
             return jsonify({
                 "success": False,
-                "error": "缺少图谱ID"
+                "error": get_error_message('missing_graph_id', report_lang)
             }), 400
 
         simulation_requirement = project.simulation_requirement or ""
+        report_language = report_lang
 
-        # 创建Agent并进行对话
+        # 创建Agent并进行对话（使用用户选择的语言）
         agent = ReportAgent(
             graph_id=graph_id,
             simulation_id=simulation_id,
-            simulation_requirement=simulation_requirement
+            simulation_requirement=simulation_requirement,
+            report_language=report_language
         )
 
         result = agent.chat(message=message, chat_history=chat_history)

diff --git a/backend/app/services/ontology_generator.py b/backend/app/services/ontology_generator.py
@@ -168,7 +168,8 @@ def generate(
         self,
         document_texts: List[str],
         simulation_requirement: str,
-        additional_context: Optional[str] = None
+        additional_context: Optional[str] = None,
+        language: str = 'zh'
     ) -> Dict[str, Any]:
         """
         生成本体定义
@@ -177,10 +178,20 @@ def generate(
             document_texts: 文档文本列表
             simulation_requirement: 模拟需求描述
             additional_context: 额外上下文
+            language: 输出语言 ('zh' 或 'en')，用于 analysis_summary 等字段
 
         Returns:
             本体定义（entity_types, edge_types等）
         """
+        self._language = language
+        # 语言指令：让 LLM 的 analysis_summary 等自然语言输出与用户语言一致
+        lang_instruction = (
+            "\n\n**语言要求**：analysis_summary 必须使用中文撰写。"
+            if language == 'zh' else
+            "\n\n**Language requirement**: You MUST write analysis_summary in English."
+        )
+        system_prompt = ONTOLOGY_SYSTEM_PROMPT + lang_instruction
+
         # 构建用户消息
         user_message = self._build_user_message(
             document_texts, 
@@ -189,7 +200,7 @@ def generate(
         )
 
         messages = [
-            {"role": "system", "content": ONTOLOGY_SYSTEM_PROMPT},
+            {"role": "system", "content": system_prompt},
             {"role": "user", "content": user_message}
         ]
 

diff --git a/backend/app/services/report_agent.py b/backend/app/services/report_agent.py
@@ -587,6 +587,10 @@ def to_dict(self) -> Dict[str, Any]:
 
 注意：sections数组最少2个，最多5个元素！"""
 
+# 语言指令（根据 report_language 动态追加到各 prompt）
+LANGUAGE_INSTRUCTION_ZH = "\n\n【语言要求】报告标题、摘要、章节标题和内容描述必须全部使用中文撰写。"
+LANGUAGE_INSTRUCTION_EN = "\n\n【Language requirement】You MUST write the report title, summary, section titles and all content in English only. Think and respond in English."
+
 PLAN_USER_PROMPT_TEMPLATE = """\
 【预测场景设定】
 我们向模拟世界注入的变量（模拟需求）：{simulation_requirement}
@@ -653,8 +657,7 @@ def to_dict(self) -> Dict[str, Any]:
 
 3. 【语言一致性 - 引用内容必须翻译为报告语言】
    - 工具返回的内容可能包含英文或中英文混杂的表述
-   - 如果模拟需求和材料原文是中文的，报告必须全部使用中文撰写
-   - 当你引用工具返回的英文或中英混杂内容时，必须将其翻译为流畅的中文后再写入报告
+   - {language_consistency_rule}
    - 翻译时保持原意不变，确保表述自然通顺
    - 这一规则同时适用于正文和引用块（> 格式）中的内容
 
@@ -851,7 +854,9 @@ def to_dict(self) -> Dict[str, Any]:
 【回答风格】
 - 简洁直接，不要长篇大论
 - 使用 > 格式引用关键内容
-- 优先给出结论，再解释原因"""
+- 优先给出结论，再解释原因
+
+【语言】{chat_language_instruction}"""
 
 CHAT_OBSERVATION_SUFFIX = "\n\n请简洁回答问题。"
 
@@ -886,7 +891,8 @@ def __init__(
         simulation_id: str,
         simulation_requirement: str,
         llm_client: Optional[LLMClient] = None,
-        zep_tools: Optional[ZepToolsService] = None
+        zep_tools: Optional[ZepToolsService] = None,
+        report_language: str = 'zh'
     ):
         """
         初始化Report Agent
@@ -897,10 +903,12 @@ def __init__(
             simulation_requirement: 模拟需求描述
             llm_client: LLM客户端（可选）
             zep_tools: Zep工具服务（可选）
+            report_language: 报告输出语言 'zh' 或 'en'，LLM 将用该语言思考和生成
         """
         self.graph_id = graph_id
         self.simulation_id = simulation_id
         self.simulation_requirement = simulation_requirement
+        self.report_language = report_language if report_language in ('zh', 'en') else 'zh'
 
         self.llm = llm_client or LLMClient()
         self.zep_tools = zep_tools or ZepToolsService()
@@ -1162,7 +1170,8 @@ def plan_outline(
         if progress_callback:
             progress_callback("planning", 30, "正在生成报告大纲...")
 
-        system_prompt = PLAN_SYSTEM_PROMPT
+        lang_inst = LANGUAGE_INSTRUCTION_ZH if self.report_language == 'zh' else LANGUAGE_INSTRUCTION_EN
+        system_prompt = PLAN_SYSTEM_PROMPT + lang_inst
         user_prompt = PLAN_USER_PROMPT_TEMPLATE.format(
             simulation_requirement=self.simulation_requirement,
             total_nodes=context.get('graph_statistics', {}).get('total_nodes', 0),
@@ -1251,9 +1260,15 @@ def _generate_section_react(
         if self.report_logger:
             self.report_logger.log_section_start(section.title, section_index)
 
+        lang_rule = (
+            "报告必须全部使用中文撰写。当你引用工具返回的英文或中英混杂内容时，必须将其翻译为流畅的中文后再写入报告。"
+            if self.report_language == 'zh' else
+            "The report MUST be written entirely in English. When you quote content from tools that is in Chinese or mixed language, translate it into fluent English before including it in the report."
+        )
         system_prompt = SECTION_SYSTEM_PROMPT_TEMPLATE.format(
             report_title=outline.title,
             report_summary=outline.summary,
+            language_consistency_rule=lang_rule,
             simulation_requirement=self.simulation_requirement,
             section_title=section.title,
             tools_description=self._get_tools_description(),
@@ -1800,10 +1815,12 @@ def chat(
         except Exception as e:
             logger.warning(f"获取报告内容失败: {e}")
 
+        chat_lang = "回复必须使用中文。" if self.report_language == 'zh' else "You MUST respond in English only."
         system_prompt = CHAT_SYSTEM_PROMPT_TEMPLATE.format(
             simulation_requirement=self.simulation_requirement,
             report_content=report_content if report_content else "（暂无报告）",
             tools_description=self._get_tools_description(),
+            chat_language_instruction=chat_lang,
         )
 
         # 构建消息

diff --git a/backend/app/utils/error_messages.py b/backend/app/utils/error_messages.py
@@ -0,0 +1,26 @@
+"""
+Error messages in zh/en for API responses.
+"""
+
+MESSAGES = {
+    'zh': {
+        'missing_simulation_id': '请提供 simulation_id',
+        'missing_message': '请提供 message',
+        'simulation_not_found': '模拟不存在',
+        'project_not_found': '项目不存在',
+        'missing_graph_id': '缺少图谱ID',
+    },
+    'en': {
+        'missing_simulation_id': 'Please provide simulation_id',
+        'missing_message': 'Please provide message',
+        'simulation_not_found': 'Simulation not found',
+        'project_not_found': 'Project not found',
+        'missing_graph_id': 'Missing graph ID',
+    },
+}
+
+
+def get_error_message(key: str, locale: str = 'zh') -> str:
+    """Return localized error message. Fallback to zh if key missing for locale."""
+    lang = 'en' if locale == 'en' else 'zh'
+    return MESSAGES.get(lang, MESSAGES['zh']).get(key, MESSAGES['zh'].get(key, str(key)))
diff --git a/backend/app/utils/request_locale.py b/backend/app/utils/request_locale.py
@@ -0,0 +1,28 @@
+"""
+从请求中获取用户选择的语言（用于 LLM 输出语言）
+支持 X-Locale 请求头或 JSON body 中的 locale 参数
+"""
+from flask import request
+
+
+def get_request_locale(default: str = 'zh') -> str:
+    """
+    从当前请求中获取语言偏好。
+
+    - X-Locale: en 或 zh
+    - 或 request.get_json().get('locale')
+    - 或 request.form.get('locale')
+
+    Returns:
+        'en' 或 'zh'
+    """
+    locale = request.headers.get('X-Locale', '').strip().lower()
+    if not locale and request.is_json:
+        data = request.get_json(silent=True) or {}
+        locale = (data.get('locale') or data.get('language') or '').strip().lower()
+    if not locale:
+        locale = (request.form.get('locale') or request.form.get('language') or '').strip().lower()
+
+    if locale in ('en', 'zh'):
+        return locale
+    return default
diff --git a/frontend/package.json b/frontend/package.json
@@ -12,6 +12,7 @@
     "axios": "^1.13.2",
     "d3": "^7.9.0",
     "vue": "^3.5.24",
+    "vue-i18n": "^9.14.5",
     "vue-router": "^4.6.3"
   },
   "devDependencies": {

diff --git a/frontend/src/App.vue b/frontend/src/App.vue
@@ -3,7 +3,15 @@
 </template>
 
 <script setup>
-// 使用 Vue Router 来管理页面
+import { onMounted } from 'vue'
+import { useI18n } from 'vue-i18n'
+import { getStoredLocale } from './i18n'
+
+// Sync html lang attribute on mount
+onMounted(() => {
+  const locale = getStoredLocale()
+  document.documentElement.lang = locale === 'zh' ? 'zh-CN' : 'en'
+})
 </script>
 
 <style>

diff --git a/frontend/src/api/index.js b/frontend/src/api/index.js
@@ -1,4 +1,5 @@
 import axios from 'axios'
+import { getApiLocale } from '../i18n'
 
 // 创建axios实例
 const service = axios.create({
@@ -9,9 +10,13 @@ const service = axios.create({
   }
 })
 
-// 请求拦截器
+// 请求拦截器 - 添加用户选择的语言，供后端 LLM 使用
 service.interceptors.request.use(
   config => {
+    const locale = getApiLocale()
+    if (locale) {
+      config.headers['X-Locale'] = locale
+    }
     return config
   },
   error => {