feat: 支持多语言提示词本地化和界面优化

- 添加 prompt_locale 参数支持简体中文、繁体中文和英文提示词本地化
- 移除内置 agents 配置以简化系统架构
- 更新 ContextBuilder 使用动态提示词模板而非硬编码内容
- 在 AgentLoop、Web 接口和 AgentService 中传递 locale 参数
- 添加输出语言指令确保用户界面内容按指定语言生成
- 扩展前端 LanguageSwitcher 组件支持三种语言选项
- 优化 Header 和侧边栏组件的响应式布局和文本截断处理
- 更新测试用例验证不同语言环境下的提示词正确性

app-instance/backend/agents/registry.json

@@ -1,145 +1,4 @@
 {
-  "agents": [
-    {
-      "agent_id": "researcher",
-      "capabilities": [
-        "research",
-        "analysis",
-        "source review",
-        "requirements"
-      ],
-      "created_at": "2026-05-27T05:25:11.756341+00:00",
-      "description": "Finds facts, references, constraints, and implementation options.",
-      "display_name": "Researcher",
-      "metadata": {},
-      "model": null,
-      "name": "researcher",
-      "priority": 50,
-      "provider_name": null,
-      "role": "research",
-      "skill_names": [],
-      "source": "builtin",
-      "status": "active",
-      "system_prompt": "You are a research specialist. Gather concise evidence and tradeoffs for the parent task.",
-      "tags": [
-        "planning",
-        "research"
-      ],
-      "tool_hints": [],
-      "updated_at": "2026-05-27T05:25:11.756349+00:00"
-    },
-    {
-      "agent_id": "implementer",
-      "capabilities": [
-        "implementation",
-        "coding",
-        "refactor",
-        "integration"
-      ],
-      "created_at": "2026-05-27T05:25:11.756351+00:00",
-      "description": "Builds scoped implementation slices and proposes concrete changes.",
-      "display_name": "Implementer",
-      "metadata": {},
-      "model": null,
-      "name": "implementer",
-      "priority": 45,
-      "provider_name": null,
-      "role": "implementation",
-      "skill_names": [],
-      "source": "builtin",
-      "status": "active",
-      "system_prompt": "You are an implementation specialist. Produce practical, scoped implementation output.",
-      "tags": [
-        "coding",
-        "build"
-      ],
-      "tool_hints": [],
-      "updated_at": "2026-05-27T05:25:11.756353+00:00"
-    },
-    {
-      "agent_id": "reviewer",
-      "capabilities": [
-        "review",
-        "quality",
-        "risk",
-        "verification"
-      ],
-      "created_at": "2026-05-27T05:25:11.756355+00:00",
-      "description": "Reviews plans, code, outputs, and risks before final synthesis.",
-      "display_name": "Reviewer",
-      "metadata": {},
-      "model": null,
-      "name": "reviewer",
-      "priority": 45,
-      "provider_name": null,
-      "role": "review",
-      "skill_names": [],
-      "source": "builtin",
-      "status": "active",
-      "system_prompt": "You are a review specialist. Focus on defects, missing requirements, and risks.",
-      "tags": [
-        "review",
-        "quality"
-      ],
-      "tool_hints": [],
-      "updated_at": "2026-05-27T05:25:11.756356+00:00"
-    },
-    {
-      "agent_id": "tester",
-      "capabilities": [
-        "testing",
-        "verification",
-        "regression",
-        "qa"
-      ],
-      "created_at": "2026-05-27T05:25:11.756358+00:00",
-      "description": "Designs and executes verification checks for task outputs.",
-      "display_name": "Tester",
-      "metadata": {},
-      "model": null,
-      "name": "tester",
-      "priority": 40,
-      "provider_name": null,
-      "role": "testing",
-      "skill_names": [],
-      "source": "builtin",
-      "status": "active",
-      "system_prompt": "You are a testing specialist. Identify focused checks and report pass/fail evidence.",
-      "tags": [
-        "test",
-        "quality"
-      ],
-      "tool_hints": [],
-      "updated_at": "2026-05-27T05:25:11.756358+00:00"
-    },
-    {
-      "agent_id": "documenter",
-      "capabilities": [
-        "documentation",
-        "explanation",
-        "migration notes",
-        "release notes"
-      ],
-      "created_at": "2026-05-27T05:25:11.756360+00:00",
-      "description": "Writes and reconciles user-facing and internal documentation updates.",
-      "display_name": "Documenter",
-      "metadata": {},
-      "model": null,
-      "name": "documenter",
-      "priority": 35,
-      "provider_name": null,
-      "role": "documentation",
-      "skill_names": [],
-      "source": "builtin",
-      "status": "active",
-      "system_prompt": "You are a documentation specialist. Produce concise docs aligned with the implementation.",
-      "tags": [
-        "docs",
-        "communication"
-      ],
-      "tool_hints": [],
-      "updated_at": "2026-05-27T05:25:11.756360+00:00"
-    }
-  ],
+  "agents": [],
   "version": 1
 }

app-instance/backend/beaver/engine/context/builder.py

@@ -27,13 +27,7 @@ from dataclasses import dataclass, field
 from typing import Any
 
 from beaver.memory.curated.snapshot import MemorySnapshot
-
-
-BEAVER_USER_ASSISTANT_IDENTITY_PROMPT = (
-    "You are 海狸 (Beaver), an AI assistant developed by 博维资讯系统有限公司. "
-    "When communicating with users, keep this identity consistent. "
-    "If users ask who you are, say that you are 海狸 (Beaver), 博维资讯系统有限公司研发的 AI 助手."
-)
+from beaver.prompts import get_main_agent_prompt
 
 
 @dataclass(slots=True)
@@ -113,6 +107,7 @@ class ContextBuildInput:
     """
 
     base_system_prompt: str = ""
+    prompt_locale: str | None = None
     history: list[dict[str, Any]] = field(default_factory=list)
     current_user_input: str | list[dict[str, Any]] | None = None
     memory_snapshot: MemorySnapshot | None = None
@@ -171,7 +166,7 @@ class ContextBuilder:
         - activated skill 正文放到显式消息里，避免 system prompt 持续膨胀
         """
 
-        sections: list[str] = [BEAVER_USER_ASSISTANT_IDENTITY_PROMPT]
+        sections: list[str] = [get_main_agent_prompt(build_input.prompt_locale)]
 
         base_system_prompt = (build_input.base_system_prompt or "").strip()
         if base_system_prompt:

app-instance/backend/beaver/engine/loop.py

@@ -224,6 +224,7 @@ class AgentLoop:
         title: str | None = None,
         execution_context: str | None = None,
         skill_selection_context: str | None = None,
+        prompt_locale: str | None = None,
         model: str | None = None,
         provider_name: str | None = None,
         api_key: str | None = None,
@@ -275,6 +276,7 @@ class AgentLoop:
             title=title,
             execution_context=execution_context,
             skill_selection_context=skill_selection_context,
+            prompt_locale=prompt_locale,
             model=model,
             provider_name=provider_name,
             api_key=api_key,
@@ -314,6 +316,7 @@ class AgentLoop:
         title: str | None = None,
         execution_context: str | None = None,
         skill_selection_context: str | None = None,
+        prompt_locale: str | None = None,
         model: str | None = None,
         provider_name: str | None = None,
         api_key: str | None = None,
@@ -572,6 +575,7 @@ class AgentLoop:
 
             build_input = ContextBuildInput(
                 base_system_prompt=self.profile.system_prompt,
+                prompt_locale=prompt_locale,
                 history=session_manager.get_history(
                     resolved_session_id,
                     max_messages=max(1, self.profile.max_context_messages),

app-instance/backend/beaver/interfaces/web/app.py

@@ -2463,6 +2463,7 @@ def create_app(
                 "user_id": payload.user_id,
                 "title": payload.title,
                 "execution_context": payload.execution_context,
+                "prompt_locale": payload.prompt_locale,
                 "model": payload.model,
                 "provider_name": payload.provider_name,
                 "embedding_model": payload.embedding_model,
@@ -2578,6 +2579,7 @@ def create_app(
                         "user_id": _clean_text(payload.get("user_id")) or None,
                         "title": _clean_text(payload.get("title")) or None,
                         "execution_context": _clean_text(payload.get("execution_context")) or None,
+                        "prompt_locale": _clean_text(payload.get("prompt_locale")) or None,
                         "model": _clean_text(payload.get("model")) or None,
                         "provider_name": _clean_text(payload.get("provider_name")) or None,
                         "embedding_model": _clean_text(payload.get("embedding_model")) or None,

app-instance/backend/beaver/interfaces/web/schemas/chat.py

@@ -55,6 +55,7 @@ class WebChatRequest(BaseModel):
     user_id: str | None = None
     title: str | None = None
     execution_context: str | None = None
+    prompt_locale: str | None = None
     model: str | None = None
     provider_name: str | None = None
     embedding_model: str | None = None

app-instance/backend/beaver/prompts/__init__.py

@@ -0,0 +1,5 @@
+"""Prompt templates used by Beaver runtime components."""
+
+from .main_agent import get_main_agent_prompt
+
+__all__ = ["get_main_agent_prompt"]

app-instance/backend/beaver/prompts/main_agent.py

@@ -0,0 +1,55 @@
+"""Locale-aware main agent prompt loading."""
+
+from __future__ import annotations
+
+from functools import lru_cache
+from pathlib import Path
+
+DEFAULT_MAIN_AGENT_PROMPT_LOCALE = "zh-Hans"
+
+_PROMPT_FILES = {
+    "zh-Hans": "zh-Hans.md",
+    "zh-Hant": "zh-Hant.md",
+    "en": "en.md",
+}
+
+_LOCALE_ALIASES = {
+    "zh": "zh-Hans",
+    "zh-cn": "zh-Hans",
+    "zh-hans": "zh-Hans",
+    "zh-sg": "zh-Hans",
+    "zh-hant": "zh-Hant",
+    "zh-tw": "zh-Hant",
+    "zh-hk": "zh-Hant",
+    "zh-mo": "zh-Hant",
+    "en": "en",
+    "en-us": "en",
+    "en-gb": "en",
+}
+
+
+def get_main_agent_prompt(locale: str | None = None) -> str:
+    """Return the main-agent identity prompt for a prompt locale."""
+
+    prompt_locale = normalize_main_agent_prompt_locale(locale)
+    return _load_main_agent_prompt(prompt_locale)
+
+
+def normalize_main_agent_prompt_locale(locale: str | None = None) -> str:
+    cleaned = (locale or DEFAULT_MAIN_AGENT_PROMPT_LOCALE).strip()
+    if not cleaned:
+        return DEFAULT_MAIN_AGENT_PROMPT_LOCALE
+    normalized = _LOCALE_ALIASES.get(cleaned.lower())
+    if normalized:
+        return normalized
+    return cleaned if cleaned in _PROMPT_FILES else DEFAULT_MAIN_AGENT_PROMPT_LOCALE
+
+
+@lru_cache(maxsize=len(_PROMPT_FILES))
+def _load_main_agent_prompt(locale: str) -> str:
+    filename = _PROMPT_FILES.get(locale, _PROMPT_FILES[DEFAULT_MAIN_AGENT_PROMPT_LOCALE])
+    path = Path(__file__).with_name("main_agent") / filename
+    if not path.exists():
+        fallback_path = Path(__file__).with_name("main_agent") / _PROMPT_FILES[DEFAULT_MAIN_AGENT_PROMPT_LOCALE]
+        return fallback_path.read_text(encoding="utf-8").strip()
+    return path.read_text(encoding="utf-8").strip()

app-instance/backend/beaver/prompts/main_agent/en.md

@@ -0,0 +1,7 @@
+You are Beaver, an AI assistant developed by Boway Information Systems Co., Ltd.
+
+When communicating with users, keep this identity consistent. If users ask who you are, say that you are Beaver, an AI assistant developed by Boway Information Systems Co., Ltd.
+
+# Language
+
+Use English for user-facing replies, task titles, summaries, plans, and final reports while this prompt is active. If the user explicitly asks for another language, follow that request.

app-instance/backend/beaver/prompts/main_agent/zh-Hans.md

@@ -0,0 +1,7 @@
+你是海狸 (Beaver)，博维资讯系统有限公司研发的 AI 助手。
+
+与用户沟通时，保持这个身份一致。用户问你是谁时，说明你是海狸 (Beaver)，博维资讯系统有限公司研发的 AI 助手。
+
+# 语言
+
+使用简体中文进行面向用户的回复、任务标题、摘要、计划和最终报告。若用户明确要求其他语言，则按用户要求执行。

app-instance/backend/beaver/prompts/main_agent/zh-Hant.md

@@ -0,0 +1,7 @@
+你是海狸 (Beaver)，博維資訊系統有限公司研發的 AI 助手。
+
+與使用者溝通時，保持這個身份一致。使用者問你是誰時，說明你是海狸 (Beaver)，博維資訊系統有限公司研發的 AI 助手。
+
+# 語言
+
+使用繁體中文進行面向使用者的回覆、任務標題、摘要、計劃和最終報告。若使用者明確要求其他語言，則按使用者要求執行。

app-instance/backend/beaver/services/agent_service.py

@@ -22,6 +22,7 @@ from beaver.engine import AgentLoop, AgentProfile, AgentRunResult, EngineLoader
 from beaver.engine.providers import make_provider_bundle
 from beaver.foundation.events import InboundMessage, OutboundMessage
 from beaver.foundation.models import CronJob, CronRunRecord
+from beaver.prompts.main_agent import normalize_main_agent_prompt_locale
 from beaver.tasks import (
     EvidenceBuilder,
     MainAgentRouter,
@@ -622,6 +623,7 @@ class AgentService:
                 session_id=session_id,
                 description=message,
                 metadata={
+                    "prompt_locale": normalize_main_agent_prompt_locale(kwargs.get("prompt_locale")),
                     "router_reason": decision.reason,
                     **({"short_title": decision.short_title} if decision.short_title else {}),
                 },
@@ -749,6 +751,8 @@ class AgentService:
         session_manager = self._require_loaded(loaded, "session_manager")
 
         base_execution_context = kwargs.get("execution_context")
+        prompt_locale = kwargs.get("prompt_locale") or task.metadata.get("prompt_locale")
+        output_language_instruction = self._output_language_instruction(prompt_locale)
         provider_bundle = kwargs.get("provider_bundle") or self._make_provider_bundle_for_task(loaded, kwargs)
         kwargs = dict(kwargs)
         team_provider_bundle_factory = kwargs.pop("team_provider_bundle_factory", None)
@@ -843,8 +847,11 @@ class AgentService:
                 "allow_candidate_generation": False,
             }
         )
-        if team_execution_context:
-            attempt_kwargs["execution_context"] = self._join_context(base_execution_context, team_execution_context)
+        attempt_kwargs["execution_context"] = self._join_context(
+            base_execution_context,
+            output_language_instruction,
+            team_execution_context,
+        )
         if plan.is_team and team_execution_context:
             attempt_kwargs["include_tools"] = False
             attempt_kwargs["max_tool_iterations"] = 0
@@ -979,6 +986,24 @@ class AgentService:
             "short_title": decision.short_title,
         }
 
+    @staticmethod
+    def _output_language_instruction(prompt_locale: str | None) -> str:
+        locale = normalize_main_agent_prompt_locale(prompt_locale)
+        if locale == "en":
+            return (
+                "Output language: English. Use English for user-facing task titles, summaries, plans, "
+                "and final answers unless the user explicitly requests another language."
+            )
+        if locale == "zh-Hant":
+            return (
+                "輸出語言：繁體中文。除非使用者明確要求其他語言，所有面向使用者的任務標題、摘要、"
+                "計劃與最終回答都使用繁體中文。"
+            )
+        return (
+            "输出语言：简体中文。除非用户明确要求其他语言，所有面向用户的任务标题、摘要、"
+            "计划与最终回答都使用简体中文。"
+        )
+
     @staticmethod
     def _skill_names_for_run(loaded: Any, run_id: str) -> list[str]:
         store = getattr(loaded, "run_memory_store", None)

app-instance/backend/tests/unit/test_context_builder.py

@@ -26,3 +26,26 @@ def test_context_builder_injects_current_date_and_time() -> None:
     assert "Local UTC offset: +08:00" in system_prompt
     assert '"today", "tomorrow", "now", "this week", and "next month"' in system_prompt
     assert result.messages[-1] == {"role": "user", "content": "今天几号？"}
+
+
+def test_context_builder_uses_simplified_main_agent_prompt_by_default() -> None:
+    system_prompt = ContextBuilder().build_system_prompt(ContextBuildInput())
+
+    assert "你是海狸 (Beaver)" in system_prompt
+    assert "博维资讯系统有限公司研发的 AI 助手" in system_prompt
+    assert "使用简体中文进行面向用户的回复" in system_prompt
+
+
+def test_context_builder_uses_traditional_main_agent_prompt_for_zh_hant() -> None:
+    system_prompt = ContextBuilder().build_system_prompt(ContextBuildInput(prompt_locale="zh-Hant"))
+
+    assert "你是海狸 (Beaver)" in system_prompt
+    assert "博維資訊系統有限公司研發的 AI 助手" in system_prompt
+    assert "使用繁體中文進行面向使用者的回覆" in system_prompt
+
+
+def test_context_builder_uses_english_main_agent_prompt_for_en() -> None:
+    system_prompt = ContextBuilder().build_system_prompt(ContextBuildInput(prompt_locale="en"))
+
+    assert "You are Beaver, an AI assistant developed by Boway Information Systems Co., Ltd." in system_prompt
+    assert "Use English for user-facing replies" in system_prompt

app-instance/backend/tests/unit/test_task_mode_feedback.py

@@ -15,6 +15,7 @@ class StubProvider(LLMProvider):
     def __init__(self, responses: list[LLMResponse]) -> None:
         super().__init__()
         self._responses = list(responses)
+        self.seen_messages: list[list[dict]] = []
 
     async def chat(
         self,
@@ -26,6 +27,7 @@ class StubProvider(LLMProvider):
     ) -> LLMResponse:
         if not self._responses:
             raise AssertionError("No stubbed provider responses left")
+        self.seen_messages.append(messages)
         return self._responses.pop(0)
 
     def get_default_model(self) -> str:
@@ -99,6 +101,52 @@ def test_task_run_records_evidence_and_waits_for_acceptance(tmp_path: Path) -> N
     assert "validated" not in event_types
 
 
+def test_task_mode_injects_prompt_locale_output_language(tmp_path: Path) -> None:
+    service = AgentService(
+        loader=EngineLoader(
+            workspace=tmp_path,
+            task_execution_planner=StubTaskExecutionPlanner(),
+        )
+    )
+    main_provider = StubProvider(
+        [
+            LLMResponse(
+                content="Done",
+                finish_reason="stop",
+                provider_name="stub",
+                model="stub-model",
+            )
+        ]
+    )
+    bundle = ProviderBundle(
+        main_runtime=SimpleNamespace(model="stub-model", provider_name="stub"),
+        main_provider=main_provider,
+        auxiliary_runtime=SimpleNamespace(model="stub-model", provider_name="stub"),
+        auxiliary_provider=StubProvider([_route_response("new_task", "Product summary")]),
+    )
+
+    result = asyncio.run(
+        service.process_direct(
+            "Summarize the uploaded report in English",
+            session_id="web:locale-task",
+            prompt_locale="en",
+            provider_bundle=bundle,
+        )
+    )
+
+    assert result.task_id
+    assert main_provider.seen_messages
+    system_prompt = main_provider.seen_messages[-1][0]["content"]
+    assert "Use English for user-facing replies" in system_prompt
+    assert "Output language: English." in system_prompt
+
+    task_service = service.create_loop().boot().task_service
+    assert task_service is not None
+    task = task_service.get_task(result.task_id)
+    assert task is not None
+    assert task.metadata["prompt_locale"] == "en"
+
+
 def test_unrelated_simple_chat_auto_accepts_active_task(tmp_path: Path) -> None:
     service = AgentService(
         loader=EngineLoader(

app-instance/backend/tests/unit/test_websocket_chat.py

@@ -73,6 +73,7 @@ def test_websocket_message_returns_chat_metadata_and_session_updated() -> None:
                 {
                     "type": "message",
                     "content": "hello",
+                    "prompt_locale": "zh-Hant",
                     "metadata": {"source": "test"},
                     "attachments": [{"file_id": "file-1", "name": "a.txt"}],
                 }
@@ -89,6 +90,7 @@ def test_websocket_message_returns_chat_metadata_and_session_updated() -> None:
             "user_id": None,
             "title": None,
             "execution_context": None,
+            "prompt_locale": "zh-Hant",
             "model": None,
             "provider_name": None,
             "embedding_model": None,
@@ -134,6 +136,7 @@ def test_websocket_message_uses_direct_processing_when_loop_is_not_running() ->
             "user_id": None,
             "title": None,
             "execution_context": None,
+            "prompt_locale": None,
             "model": None,
             "provider_name": None,
             "embedding_model": None,
@@ -149,7 +152,10 @@ def test_rest_chat_uses_direct_processing_when_loop_is_not_running() -> None:
     app = create_app(service=service, manage_service_lifecycle=False)
 
     with TestClient(app) as client:
-        response = client.post("/api/chat", json={"session_id": "web:alpha", "message": "hello"})
+        response = client.post(
+            "/api/chat",
+            json={"session_id": "web:alpha", "message": "hello", "prompt_locale": "en"},
+        )
 
     assert response.status_code == 200
     assert service.calls == [
@@ -160,6 +166,7 @@ def test_rest_chat_uses_direct_processing_when_loop_is_not_running() -> None:
             "user_id": None,
             "title": None,
             "execution_context": None,
+            "prompt_locale": "en",
             "model": None,
             "provider_name": None,
             "embedding_model": None,

app-instance/frontend/app/(app)/page.tsx

@@ -23,6 +23,7 @@ import {
   getSession,
   getSessionProcess,
   listSessions,
+  promptLocaleForAppLocale,
   sendMessage,
   submitChatFeedback,
   uploadFile,
@@ -44,7 +45,7 @@ function isSessionUpdatedEvent(data: WsEvent | Record<string, unknown>): data is
   return data.type === 'session_updated' && typeof data.session_id === 'string';
 }
 
-function activeTaskStatusLabel(status: string, locale: 'zh-CN' | 'en-US') {
+function activeTaskStatusLabel(status: string, locale: string) {
   if (status === 'needs_revision') return pickAppText(locale, '待修改', 'Needs revision');
   if (status === 'awaiting_acceptance') return pickAppText(locale, '待验收', 'Awaiting acceptance');
   if (status === 'running') return pickAppText(locale, '进行中', 'Running');
@@ -140,8 +141,9 @@ export default function ChatPage() {
         liveRuns: processRuns,
         liveEvents: processEvents,
         liveArtifacts: processArtifacts,
+        locale,
       }),
-    [activeTaskDetail, processArtifacts, processEvents, processRuns]
+    [activeTaskDetail, locale, processArtifacts, processEvents, processRuns]
   );
 
   const loadSessions = useCallback(async () => {
@@ -400,6 +402,7 @@ export default function ChatPage() {
         type: 'message',
         content: msgContent,
         thinking_enabled: thinkingModeEnabled,
+        prompt_locale: promptLocaleForAppLocale(locale),
       };
       if (attachments.length > 0) {
         wsPayload.attachments = attachments;

app-instance/frontend/app/(app)/tasks/[taskId]/page.tsx

@@ -97,8 +97,9 @@ export default function TaskDetailPage() {
         liveRuns: processRuns,
         liveEvents: processEvents,
         liveArtifacts: processArtifacts,
+        locale,
       }),
-    [backendTask, processArtifacts, processEvents, processRuns]
+    [backendTask, locale, processArtifacts, processEvents, processRuns]
   );
   const timelineCards = timelineView?.cards ?? [];
 

app-instance/frontend/app/(app)/tasks/page.tsx

@@ -222,7 +222,7 @@ function OrdinaryTaskCard({
   onDelete,
 }: {
   task: BackendTask;
-  locale: 'zh-CN' | 'en-US';
+  locale: string;
   onDelete: () => void;
 }) {
   const title = task.short_title || String(task.metadata?.short_title || '') || task.description || task.goal || task.task_id;
@@ -284,7 +284,7 @@ function OrdinaryTaskCard({
   );
 }
 
-function taskStatusLabel(status: string, locale: 'zh-CN' | 'en-US') {
+function taskStatusLabel(status: string, locale: string) {
   const labels: Record<string, [string, string]> = {
     open: ['已创建', 'Open'],
     running: ['执行中', 'Running'],
@@ -297,7 +297,7 @@ function taskStatusLabel(status: string, locale: 'zh-CN' | 'en-US') {
   return label ? pickAppText(locale, label[0], label[1]) : status;
 }
 
-function taskSourceLabel(task: BackendTask, locale: 'zh-CN' | 'en-US') {
+function taskSourceLabel(task: BackendTask, locale: string) {
   if (task.metadata?.source === 'scheduled_run') {
     return pickAppText(locale, '定时通知修改', 'Scheduled notification revision');
   }
@@ -520,7 +520,7 @@ function ScheduledJobCard({
   onRemove,
 }: {
   job: CronJob;
-  locale: 'zh-CN' | 'en-US';
+  locale: string;
   formatTime: (ms: number | null) => string;
   onToggle: (checked: boolean) => void;
   onRun: () => void;

app-instance/frontend/components/Header.tsx

@@ -155,7 +155,7 @@ const Header = () => {
             <div className="flex min-w-0 items-center gap-2">
               <button
                 type="button"
-                className="inline-flex h-11 w-11 items-center justify-center rounded-full border border-[#E6E1DE] bg-white text-[#1D1715] transition-colors hover:bg-[#F7F5F4] 2xl:hidden"
+                className="inline-flex h-11 w-11 items-center justify-center rounded-full border border-[#E6E1DE] bg-white text-[#1D1715] transition-colors hover:bg-[#F7F5F4] min-[1800px]:hidden"
                 aria-label={mobileMenuOpen ? pickAppText(locale, '关闭导航', 'Close navigation') : pickAppText(locale, '打开导航', 'Open navigation')}
                 aria-expanded={mobileMenuOpen}
                 aria-controls="app-primary-mobile-nav"
@@ -170,7 +170,7 @@ const Header = () => {
               </Link>
             </div>
 
-            <nav className="hidden items-center gap-1 rounded-full border border-[#E6E1DE] bg-white px-1.5 py-1 shadow-[0_1px_2px_rgba(0,0,0,0.04)] 2xl:flex">
+            <nav className="hidden items-center gap-1 rounded-full border border-[#E6E1DE] bg-white px-1.5 py-1 shadow-[0_1px_2px_rgba(0,0,0,0.04)] min-[1800px]:flex">
               {renderNavLinks(false)}
             </nav>
 
@@ -185,7 +185,7 @@ const Header = () => {
                     <PopoverTrigger asChild>
                       <button
                         type="button"
-                        className="flex h-11 w-11 items-center justify-center gap-2 rounded-full border border-[#E6E1DE] bg-white px-1.5 text-sm font-medium text-[#1D1715] transition-colors hover:bg-[#F7F5F4] sm:w-auto sm:justify-start sm:px-2"
+                        className="flex h-11 w-11 min-w-0 items-center justify-center gap-2 rounded-full border border-[#E6E1DE] bg-white px-1.5 text-sm font-medium text-[#1D1715] transition-colors hover:bg-[#F7F5F4] sm:w-auto sm:max-w-[11rem] sm:justify-start sm:px-2"
                         aria-label={pickAppText(locale, '打开账号菜单', 'Open account menu')}
                       >
                         <Avatar className="h-8 w-8 border border-[#E6E1DE]">
@@ -193,7 +193,7 @@ const Header = () => {
                             {userInitial}
                           </AvatarFallback>
                         </Avatar>
-                        <span className="hidden max-w-28 truncate sm:block">{user.username}</span>
+                        <span className="hidden min-w-0 max-w-24 truncate sm:block">{user.username}</span>
                         <ChevronDown className="hidden h-4 w-4 text-muted-foreground sm:block" />
                       </button>
                     </PopoverTrigger>
@@ -245,14 +245,14 @@ const Header = () => {
         <>
           <button
             type="button"
-            className="fixed inset-x-0 bottom-0 top-16 z-40 bg-black/40 2xl:hidden"
+            className="fixed inset-x-0 bottom-0 top-16 z-40 bg-black/40 min-[1800px]:hidden"
             aria-label={pickAppText(locale, '关闭导航', 'Close navigation')}
             onClick={() => setMobileMenuOpen(false)}
           />
           <nav
             id="app-primary-mobile-nav"
             aria-label={pickAppText(locale, '主导航', 'Primary navigation')}
-            className="fixed bottom-0 left-0 top-16 z-[45] isolate w-[min(86vw,320px)] overflow-y-auto border-r border-[#E6E1DE] bg-background text-foreground shadow-[12px_0_32px_rgba(29,23,21,0.24)] animate-in slide-in-from-left-full duration-200 2xl:hidden"
+            className="fixed bottom-0 left-0 top-16 z-[45] isolate w-[min(86vw,320px)] overflow-y-auto border-r border-[#E6E1DE] bg-background text-foreground shadow-[12px_0_32px_rgba(29,23,21,0.24)] animate-in slide-in-from-left-full duration-200 min-[1800px]:hidden"
           >
             <div className="min-h-full bg-background px-4 py-5">
               <div className="grid gap-2 bg-background">

app-instance/frontend/components/LanguageSwitcher.tsx

@@ -2,40 +2,49 @@
 
 import { Languages } from 'lucide-react';
 
+import {
+  Select,
+  SelectContent,
+  SelectItem,
+  SelectTrigger,
+  SelectValue,
+} from '@/components/ui/select';
+import type { AppLocale } from '@/lib/i18n/core';
+import { pickAppText } from '@/lib/i18n/core';
 import { useAppI18n } from '@/lib/i18n/provider';
 import { cn } from '@/lib/utils';
 
 const OPTIONS = [
-  { value: 'zh-CN', label: 'ZH' },
-  { value: 'en-US', label: 'EN' },
+  { value: 'zh-CN', label: '中文', shortLabel: '中' },
+  { value: 'en-US', label: 'English', shortLabel: 'EN' },
+  { value: 'zh-Hant', label: '繁體中文', shortLabel: '繁' },
 ] as const;
 
 export function LanguageSwitcher({ className }: { className?: string }) {
   const { locale, setLocale } = useAppI18n();
+  const selectedOption = OPTIONS.find((option) => option.value === locale) ?? OPTIONS[0];
 
   return (
-    <div
-      className={cn(
-        'inline-flex items-center gap-1 rounded-md border border-border bg-muted/30 p-1',
-        className
-      )}
-    >
-      <Languages className="h-3.5 w-3.5 text-muted-foreground" />
-      {OPTIONS.map((option) => (
-        <button
-          key={option.value}
-          type="button"
-          onClick={() => setLocale(option.value)}
-          className={cn(
-            'h-11 w-11 rounded text-xs font-medium transition-colors',
-            locale === option.value
-              ? 'bg-background text-foreground shadow-sm'
-              : 'text-muted-foreground hover:text-foreground'
-          )}
-        >
-          {option.label}
-        </button>
-      ))}
-    </div>
+    <Select value={locale} onValueChange={(value) => setLocale(value as AppLocale)}>
+      <SelectTrigger
+        className={cn('h-11 w-[92px] gap-1.5 bg-muted/30 px-2 sm:w-[138px] sm:gap-2 sm:px-3', className)}
+        aria-label={pickAppText(locale, '选择语言', 'Select language')}
+      >
+        <Languages className="h-3.5 w-3.5 shrink-0 text-muted-foreground" />
+        <SelectValue aria-label={selectedOption.label}>
+          <span className="min-w-0 flex-1 truncate text-left">
+            <span className="sm:hidden">{selectedOption.shortLabel}</span>
+            <span className="hidden sm:inline">{selectedOption.label}</span>
+          </span>
+        </SelectValue>
+      </SelectTrigger>
+      <SelectContent align="end">
+        {OPTIONS.map((option) => (
+          <SelectItem key={option.value} value={option.value}>
+            {option.label}
+          </SelectItem>
+        ))}
+      </SelectContent>
+    </Select>
   );
 }

app-instance/frontend/components/chat-workbench/AgentTeamBlock.tsx

@@ -6,6 +6,7 @@ import { CheckCircle2, Loader2, Sparkles } from 'lucide-react';
 import type { ProcessArtifact, ProcessEvent, ProcessRun } from '@/types';
 import { Badge } from '@/components/ui/badge';
 import { appArtifactPreview, appFeedRoleLabel, appStatusLabel } from '@/lib/i18n/common';
+import type { AppLocale } from '@/lib/i18n/core';
 import { pickAppText } from '@/lib/i18n/core';
 import { useAppI18n } from '@/lib/i18n/provider';
 import { cn } from '@/lib/utils';
@@ -84,7 +85,7 @@ function buildFeed(
   run: ProcessRun,
   events: ProcessEvent[],
   artifacts: ProcessArtifact[],
-  locale: 'zh-CN' | 'en-US',
+  locale: AppLocale,
 ): AgentFeedItem[] {
   const items: AgentFeedItem[] = [];
   let hasLeadBubble = false;
@@ -152,7 +153,7 @@ function buildFeed(
     .slice(-8);
 }
 
-function runSummary(run: ProcessRun, feed: AgentFeedItem[], locale: 'zh-CN' | 'en-US'): string {
+function runSummary(run: ProcessRun, feed: AgentFeedItem[], locale: AppLocale): string {
   if (run.summary?.trim()) {
     return run.summary.trim();
   }
@@ -262,7 +263,7 @@ function AgentBubble({
   locale,
 }: {
   item: AgentFeedItem;
-  locale: 'zh-CN' | 'en-US';
+  locale: AppLocale;
 }) {
   return (
     <div
@@ -297,7 +298,7 @@ function LiveAgentCard({
   phase: RunCardPhase;
   accentIndex: number;
   onSelect: () => void;
-  locale: 'zh-CN' | 'en-US';
+  locale: AppLocale;
 }) {
   const showSpinner = !TERMINAL_STATUSES.has(run.status);
   const accent = accentFor(accentIndex);
@@ -370,7 +371,7 @@ function ResultCard({
   selected: boolean;
   accentIndex: number;
   onSelect: () => void;
-  locale: 'zh-CN' | 'en-US';
+  locale: AppLocale;
 }) {
   const accent = accentFor(accentIndex);
 

app-instance/frontend/components/chat-workbench/ArtifactSidebar.tsx

@@ -18,7 +18,7 @@ function artifactIcon(type: ProcessArtifact['artifact_type']) {
   return <FileOutput className="w-4 h-4" />;
 }
 
-function renderArtifactBody(artifact: ProcessArtifact, locale: 'zh-CN' | 'en-US') {
+function renderArtifactBody(artifact: ProcessArtifact, locale: string) {
   if (artifact.artifact_type === 'json' && artifact.data !== undefined) {
     return (
       <pre className="text-[11px] leading-5 whitespace-pre-wrap break-words rounded-md bg-background/70 p-3 overflow-x-auto">

app-instance/frontend/components/chat-workbench/CurrentSessionProgressSidebar.tsx

@@ -21,17 +21,19 @@ function ProgressPanel({
   const { locale } = useAppI18n();
 
   return (
-    <div className="flex h-full flex-col bg-[#FBFAF9]">
-      <div className="flex h-16 shrink-0 items-center justify-between border-b border-[#E6E1DE] px-5">
-        <div>
-          <h2 className="text-base font-semibold text-foreground">
+    <div className="flex h-full min-w-0 flex-col overflow-hidden bg-[#FBFAF9]">
+      <div className="flex h-16 min-w-0 shrink-0 items-center justify-between gap-3 border-b border-[#E6E1DE] px-5">
+        <div className="min-w-0">
+          <h2 className="truncate text-base font-semibold text-foreground">
             {pickAppText(locale, '当前会话的运行进度', 'Current Session Progress')}
           </h2>
-          <p className="flex items-center gap-1.5 text-xs text-muted-foreground">
+          <p className="flex min-w-0 items-center gap-1.5 text-xs text-muted-foreground">
             {isLive ? <Activity className="h-3.5 w-3.5" /> : null}
-            {isLive
-              ? pickAppText(locale, '任务时间线实时更新', 'Task timeline updates live')
-              : pickAppText(locale, '与任务详情时间线一致', 'Matches the Task detail timeline')}
+            <span className="truncate">
+              {isLive
+                ? pickAppText(locale, '任务时间线实时更新', 'Task timeline updates live')
+                : pickAppText(locale, '与任务详情时间线一致', 'Matches the Task detail timeline')}
+            </span>
           </p>
         </div>
         {onClose ? (
@@ -46,8 +48,8 @@ function ProgressPanel({
         ) : null}
       </div>
 
-      <ScrollArea className="min-h-0 flex-1 px-4 py-4">
-        <div className="pb-6">
+      <ScrollArea className="min-h-0 min-w-0 flex-1 overflow-hidden px-4 py-4">
+        <div className="min-w-0 max-w-full pb-6">
           <TaskTimeline cards={cards} isLive={isLive} showHeader={false} />
         </div>
       </ScrollArea>
@@ -67,7 +69,7 @@ export function CurrentSessionProgressSidebar({
 
   return (
     <>
-      <aside className="hidden h-full w-[380px] shrink-0 border-l border-[#E6E1DE] xl:flex">
+      <aside className="hidden h-full w-[380px] min-w-0 shrink-0 overflow-hidden border-l border-[#E6E1DE] xl:flex">
         <ProgressPanel cards={cards} isLive={isLive} />
       </aside>
 
@@ -88,7 +90,7 @@ export function CurrentSessionProgressSidebar({
             onClick={() => setMobileOpen(false)}
             aria-label={pickAppText(locale, '关闭进度面板', 'Close progress panel')}
           />
-          <div className="absolute inset-y-0 right-0 w-[min(92vw,390px)] border-l border-[#E6E1DE] shadow-2xl">
+          <div className="absolute inset-y-0 right-0 w-[min(92vw,390px)] min-w-0 overflow-hidden border-l border-[#E6E1DE] shadow-2xl">
             <ProgressPanel cards={cards} isLive={isLive} onClose={() => setMobileOpen(false)} />
           </div>
         </div>

app-instance/frontend/components/task-detail/TaskAcceptanceCard.tsx

@@ -55,14 +55,14 @@ function feedbackKind(item: TaskFeedbackItem): string {
   return String(item.acceptance_type || item.feedback_type || '');
 }
 
-function humanFeedback(type: string, locale: 'zh-CN' | 'en-US') {
+function humanFeedback(type: string, locale: string) {
   if (type === 'accept' || type === 'satisfied') return pickAppText(locale, '接受', 'Accepted');
   if (type === 'revise') return pickAppText(locale, '请求修改', 'Revision requested');
   if (type === 'abandon') return pickAppText(locale, '放弃任务', 'Abandoned');
   return type || pickAppText(locale, '验收', 'Acceptance');
 }
 
-function humanTaskStatus(status: string, locale: 'zh-CN' | 'en-US') {
+function humanTaskStatus(status: string, locale: string) {
   const labels: Record<string, [string, string]> = {
     open: ['已创建', 'Open'],
     running: ['执行中', 'Running'],

app-instance/frontend/components/task-detail/TaskLiveHeader.tsx

@@ -24,7 +24,7 @@ function isRuntimeStatus(status: string): status is TaskRuntimeStatus {
   return RUNTIME_STATUSES.has(status);
 }
 
-function humanTaskStatus(status: string, locale: 'zh-CN' | 'en-US') {
+function humanTaskStatus(status: string, locale: string) {
   const map: Record<string, [string, string]> = {
     open: ['已创建', 'Open'],
     running: ['执行中', 'Running'],

app-instance/frontend/components/task-detail/TaskSideRail.tsx

@@ -26,7 +26,7 @@ function isRuntimeStatus(status: string): status is TaskRuntimeStatus {
   return RUNTIME_STATUSES.has(status);
 }
 
-function humanTaskStatus(status: string, locale: 'zh-CN' | 'en-US') {
+function humanTaskStatus(status: string, locale: string) {
   const map: Record<string, [string, string]> = {
     open: ['已创建', 'Open'],
     running: ['执行中', 'Running'],
@@ -47,7 +47,7 @@ function latestFeedback(task: BackendTask): Record<string, unknown> | null {
   return [...(task.feedback ?? [])].reverse()[0] ?? null;
 }
 
-function acceptanceState(task: BackendTask, locale: 'zh-CN' | 'en-US'): string {
+function acceptanceState(task: BackendTask, locale: string): string {
   const feedback = latestFeedback(task);
   const kind = String(feedback?.acceptance_type || feedback?.feedback_type || '');
   if (kind) return humanTaskStatus(kind, locale);

app-instance/frontend/components/task-detail/TaskTimelineCard.tsx

@@ -93,7 +93,7 @@ function detailsJson(details: Record<string, unknown>): string {
   }
 }
 
-function cardTypeLabel(type: TaskTimelineCardType, locale: 'zh-CN' | 'en-US') {
+function cardTypeLabel(type: TaskTimelineCardType, locale: string) {
   const labels: Record<TaskTimelineCardType, [string, string]> = {
     task_created: ['任务', 'Task'],
     plan: ['计划', 'Plan'],
@@ -114,7 +114,7 @@ function cardTypeLabel(type: TaskTimelineCardType, locale: 'zh-CN' | 'en-US') {
   return pickAppText(locale, label[0], label[1]);
 }
 
-function humanStatus(status: string, locale: 'zh-CN' | 'en-US') {
+function humanStatus(status: string, locale: string) {
   const labels: Record<string, [string, string]> = {
     open: ['已创建', 'Open'],
     running: ['执行中', 'Running'],
@@ -137,7 +137,7 @@ function historyVersions(details: Record<string, unknown> | undefined): Array<Re
   return Array.isArray(versions) ? versions.filter((item): item is Record<string, unknown> => Boolean(item) && typeof item === 'object') : [];
 }
 
-function renderHistoryStatus(version: Record<string, unknown>, locale: 'zh-CN' | 'en-US') {
+function renderHistoryStatus(version: Record<string, unknown>, locale: string) {
   const status = String(version.acceptanceType || version.status || '');
   return status ? humanStatus(status, locale) : pickAppText(locale, '历史版本', 'Previous version');
 }
@@ -184,30 +184,30 @@ export function TaskTimelineCard({ card, resultAcceptance, reviewTargetId }: Pro
   return (
     <Card id={shouldRenderResultAcceptance ? reviewTargetId : undefined} className="min-w-0 max-w-full scroll-mt-44 overflow-hidden rounded-md">
       <CardContent className="p-4">
-        <div className="flex gap-3">
+        <div className="flex min-w-0 gap-3">
           <div className="flex h-9 w-9 shrink-0 items-center justify-center rounded-md bg-muted">
             <Icon className="h-4 w-4 text-muted-foreground" />
           </div>
           <div className="min-w-0 flex-1">
-            <div className="flex items-start justify-between gap-3">
-              <div className="min-w-0 flex-1">
-                <div className="flex min-w-0 items-center gap-2">
-                  <h3 className="min-w-0 flex-1 truncate text-sm font-semibold">{card.title}</h3>
-                  <Badge variant="secondary" className="shrink-0 text-[11px]">
+            <div className="flex min-w-0 flex-wrap items-start justify-between gap-2">
+              <div className="min-w-0 flex-1 basis-44">
+                <div className="flex min-w-0 flex-wrap items-center gap-2">
+                  <h3 className={`min-w-0 flex-1 basis-32 text-sm font-semibold ${containedLongTextClass}`}>{card.title}</h3>
+                  <Badge variant="secondary" className="max-w-full text-[11px]">
                     {cardTypeLabel(card.type, locale)}
                   </Badge>
                 </div>
-                <div className="mt-1 flex flex-wrap gap-x-3 gap-y-1 text-xs text-muted-foreground">
-                  {card.actorName ? <span className={containedLongTextClass}>{card.actorName}</span> : null}
-                  <span>{formatTaskRuntimeTime(card.createdAt, locale)}</span>
-                  {card.runId ? <span className="font-mono">{card.runId.slice(0, 8)}</span> : null}
+                <div className="mt-1 flex min-w-0 flex-wrap gap-x-3 gap-y-1 text-xs text-muted-foreground">
+                  {card.actorName ? <span className={`max-w-full ${containedLongTextClass}`}>{card.actorName}</span> : null}
+                  <span className="max-w-full">{formatTaskRuntimeTime(card.createdAt, locale)}</span>
+                  {card.runId ? <span className={`max-w-full font-mono ${containedLongTextClass}`}>{card.runId.slice(0, 8)}</span> : null}
                 </div>
               </div>
               {card.status ? (
                 isRuntimeStatus(card.status) ? (
-                  <TaskRuntimeStatusBadge status={card.status} />
+                  <TaskRuntimeStatusBadge status={card.status} className={`max-w-full ${containedLongTextClass}`} />
                 ) : (
-                  <Badge variant="outline" className="shrink-0 text-[11px]">
+                  <Badge variant="outline" className={`max-w-full text-[11px] ${containedLongTextClass}`}>
                     {humanStatus(card.status, locale)}
                   </Badge>
                 )
@@ -224,7 +224,7 @@ export function TaskTimelineCard({ card, resultAcceptance, reviewTargetId }: Pro
 
             {card.type === 'result_history' ? <TaskResultHistory card={card} /> : card.details ? (
               <details className="mt-3 min-w-0 max-w-full overflow-hidden rounded-md border border-border bg-muted/20 px-3 py-2 text-xs">
-                <summary className="flex min-h-[44px] cursor-pointer select-none items-center font-medium text-muted-foreground">
+                <summary className="flex min-h-[44px] min-w-0 cursor-pointer select-none items-center font-medium text-muted-foreground">
                   {pickAppText(locale, '详情 JSON', 'Details JSON')}
                 </summary>
                 <pre className={`mt-2 max-h-72 overflow-auto text-[11px] leading-5 text-muted-foreground ${containedJsonTextClass}`}>

app-instance/frontend/components/task-runtime/TaskRuntimeShared.tsx

@@ -35,7 +35,7 @@ export function TaskRuntimeStatusBadge({
   );
 }
 
-export function formatTaskRuntimeTime(value?: string | null, locale: 'zh-CN' | 'en-US' = 'zh-CN'): string {
+export function formatTaskRuntimeTime(value?: string | null, locale: string = 'zh-CN'): string {
   if (!value) return '-';
   const date = new Date(value);
   if (Number.isNaN(date.getTime())) return value;
@@ -47,7 +47,7 @@ export function formatTaskRuntimeTime(value?: string | null, locale: 'zh-CN' | '
   }).format(date);
 }
 
-export function formatTaskRuntimeDuration(durationMs: number | null, locale: 'zh-CN' | 'en-US' = 'zh-CN'): string {
+export function formatTaskRuntimeDuration(durationMs: number | null, locale: string = 'zh-CN'): string {
   if (durationMs === null || durationMs < 0) return '-';
   if (durationMs < 1000) return locale === 'en-US' ? '<1s' : '<1秒';
 

app-instance/frontend/components/ui/select.tsx

@@ -88,7 +88,7 @@ const SelectContent = React.forwardRef<
         className={cn(
           'p-1',
           position === 'popper' &&
-            'h-[var(--radix-select-trigger-height)] w-full min-w-[var(--radix-select-trigger-width)]'
+            'w-full min-w-[var(--radix-select-trigger-width)]'
         )}
       >
         {children}

app-instance/frontend/lib/api.ts

@@ -51,7 +51,7 @@ import type {
   UiMcpServerDescriptor,
   WsEvent,
 } from '@/types';
-import { getCurrentAppLocale, pickAppText } from '@/lib/i18n/core';
+import { getCurrentAppLocale, pickAppText, type AppLocale } from '@/lib/i18n/core';
 
 const API_URL = process.env.NEXT_PUBLIC_API_URL?.trim();
 const WS_URL = process.env.NEXT_PUBLIC_WS_URL?.trim();
@@ -62,6 +62,15 @@ const REQUEST_TIMEOUT_MS = 8000;
 const OUTLOOK_REQUEST_TIMEOUT_MS = 45000;
 const SKILL_LEARNING_REQUEST_TIMEOUT_MS = 120000;
 
+export type PromptLocale = 'zh-Hans' | 'zh-Hant' | 'en';
+
+export function promptLocaleForAppLocale(locale: AppLocale): PromptLocale {
+  if (locale === 'zh-Hant') {
+    return 'zh-Hant';
+  }
+  return locale === 'en-US' ? 'en' : 'zh-Hans';
+}
+
 function isBrowser(): boolean {
   return typeof window !== 'undefined';
 }
@@ -271,6 +280,7 @@ export async function sendMessage(
     replyToScheduledRunId?: string;
     scheduledReplyIntent?: 'revise_once' | 'update_future' | 'continue_task';
     thinkingEnabled?: boolean;
+    promptLocale?: PromptLocale;
   }
 ): Promise<{
   response?: string;
@@ -281,7 +291,11 @@ export async function sendMessage(
   task_status?: string | null;
   evidence_status?: string | null;
 }> {
-  const body: Record<string, unknown> = { message, session_id: sessionId };
+  const body: Record<string, unknown> = {
+    message,
+    session_id: sessionId,
+    prompt_locale: options?.promptLocale || promptLocaleForAppLocale(getCurrentAppLocale()),
+  };
   if (attachments && attachments.length > 0) {
     body.attachments = attachments;
   }
@@ -356,7 +370,11 @@ export function streamMessage(
       const res = await fetch(buildApiUrl('/api/chat/stream'), {
         method: 'POST',
         headers: authHeaders(),
-        body: JSON.stringify({ message, session_id: sessionId }),
+        body: JSON.stringify({
+          message,
+          session_id: sessionId,
+          prompt_locale: promptLocaleForAppLocale(getCurrentAppLocale()),
+        }),
         signal: controller.signal,
       });
 

app-instance/frontend/lib/i18n/core.test.ts

@@ -0,0 +1,32 @@
+import { describe, expect, it } from 'vitest';
+
+import { isAppLocale, normalizeAppLocale, pickAppText } from '@/lib/i18n/core';
+
+describe('app locale normalization', () => {
+  it('accepts simplified Chinese, English, and traditional Chinese locales', () => {
+    expect(isAppLocale('zh-CN')).toBe(true);
+    expect(isAppLocale('en-US')).toBe(true);
+    expect(isAppLocale('zh-Hant')).toBe(true);
+  });
+
+  it('normalizes common traditional Chinese locale tags', () => {
+    expect(normalizeAppLocale('zh-TW')).toBe('zh-Hant');
+    expect(normalizeAppLocale('zh-HK')).toBe('zh-Hant');
+    expect(normalizeAppLocale('zh-Hant')).toBe('zh-Hant');
+  });
+});
+
+describe('app text picker', () => {
+  it('returns simplified Chinese text for zh-CN', () => {
+    expect(pickAppText('zh-CN', '任务状态', 'Task status')).toBe('任务状态');
+  });
+
+  it('returns English text for en-US', () => {
+    expect(pickAppText('en-US', '任务状态', 'Task status')).toBe('Task status');
+  });
+
+  it('returns traditional Chinese text for zh-Hant', () => {
+    expect(pickAppText('zh-Hant', '任务状态', 'Task status')).toBe('任務狀態');
+    expect(pickAppText('zh-Hant', '智能体结果', 'Agent results')).toBe('智慧體結果');
+  });
+});

app-instance/frontend/lib/i18n/core.ts

@@ -1,12 +1,12 @@
 export const APP_LOCALE_COOKIE = 'beaver_locale';
 export const APP_LOCALE_STORAGE_KEY = 'beaver_locale';
 
-export const APP_LOCALES = ['zh-CN', 'en-US'] as const;
+export const APP_LOCALES = ['zh-CN', 'en-US', 'zh-Hant'] as const;
 
 export type AppLocale = (typeof APP_LOCALES)[number];
 
 export function isAppLocale(value: string | null | undefined): value is AppLocale {
-  return value === 'zh-CN' || value === 'en-US';
+  return value === 'zh-CN' || value === 'en-US' || value === 'zh-Hant';
 }
 
 export function normalizeAppLocale(value?: string | null): AppLocale {
@@ -14,6 +14,14 @@ export function normalizeAppLocale(value?: string | null): AppLocale {
   if (probe.startsWith('en')) {
     return 'en-US';
   }
+  if (
+    probe === 'zh-hant' ||
+    probe.startsWith('zh-tw') ||
+    probe.startsWith('zh-hk') ||
+    probe.startsWith('zh-mo')
+  ) {
+    return 'zh-Hant';
+  }
   return 'zh-CN';
 }
 
@@ -71,6 +79,507 @@ export function getCurrentAppLocale(): AppLocale {
   return readBrowserAppLocale();
 }
 
-export function pickAppText<T>(locale: AppLocale, zhValue: T, enValue: T): T {
-  return locale === 'en-US' ? enValue : zhValue;
+export function pickAppText<T>(locale: string | null | undefined, zhValue: T, enValue: T): T {
+  const appLocale = normalizeAppLocale(locale);
+  if (appLocale === 'en-US') {
+    return enValue;
+  }
+  if (appLocale === 'zh-Hant') {
+    return toTraditionalValue(zhValue);
+  }
+  return zhValue;
+}
+
+function toTraditionalValue<T>(value: T): T {
+  return typeof value === 'string' ? (toTraditionalChinese(value) as T) : value;
+}
+
+const SIMPLIFIED_TO_TRADITIONAL_PHRASES: Array<[string, string]> = [
+  ['智能体', '智慧體'],
+  ['Agent Team', 'Agent Team'],
+];
+
+const SIMPLIFIED_TO_TRADITIONAL_CHARS: Record<string, string> = {
+  个: '個',
+  为: '為',
+  么: '麼',
+  义: '義',
+  习: '習',
+  书: '書',
+  了: '了',
+  于: '於',
+  云: '雲',
+  产: '產',
+  仅: '僅',
+  从: '從',
+  仓: '倉',
+  仪: '儀',
+  们: '們',
+  优: '優',
+  会: '會',
+  传: '傳',
+  体: '體',
+  余: '餘',
+  侧: '側',
+  侦: '偵',
+  促: '促',
+  俩: '倆',
+  值: '值',
+  假: '假',
+  做: '做',
+  停: '停',
+  储: '儲',
+  像: '像',
+  儿: '兒',
+  先: '先',
+  光: '光',
+  关: '關',
+  兴: '興',
+  具: '具',
+  内: '內',
+  册: '冊',
+  写: '寫',
+  军: '軍',
+  农: '農',
+  况: '況',
+  冻: '凍',
+  净: '淨',
+  准: '準',
+  几: '幾',
+  击: '擊',
+  划: '劃',
+  则: '則',
+  创: '創',
+  初: '初',
+  删: '刪',
+  别: '別',
+  到: '到',
+  制: '製',
+  剂: '劑',
+  剩: '剩',
+  办: '辦',
+  功: '功',
+  加: '加',
+  务: '務',
+  动: '動',
+  助: '助',
+  势: '勢',
+  包: '包',
+  区: '區',
+  协: '協',
+  单: '單',
+  卖: '賣',
+  占: '佔',
+  卡: '卡',
+  历: '歷',
+  压: '壓',
+  厕: '廁',
+  厢: '廂',
+  县: '縣',
+  参: '參',
+  双: '雙',
+  发: '發',
+  变: '變',
+  叠: '疊',
+  号: '號',
+  后: '後',
+  向: '向',
+  吗: '嗎',
+  启: '啟',
+  员: '員',
+  命: '命',
+  咨: '諮',
+  哑: '啞',
+  响: '響',
+  唤: '喚',
+  问: '問',
+  單: '單',
+  喂: '餵',
+  器: '器',
+  团: '團',
+  园: '園',
+  困: '困',
+  图: '圖',
+  场: '場',
+  块: '塊',
+  坏: '壞',
+  址: '址',
+  坚: '堅',
+  坛: '壇',
+  型: '型',
+  垃: '垃',
+  域: '域',
+  堆: '堆',
+  填: '填',
+  增: '增',
+  墙: '牆',
+  声: '聲',
+  处: '處',
+  备: '備',
+  复: '復',
+  够: '夠',
+  头: '頭',
+  奖: '獎',
+  好: '好',
+  如: '如',
+  始: '始',
+  委: '委',
+  存: '存',
+  学: '學',
+  宁: '寧',
+  它: '它',
+  安: '安',
+  完: '完',
+  实: '實',
+  审: '審',
+  客: '客',
+  宪: '憲',
+  宽: '寬',
+  对: '對',
+  导: '導',
+  将: '將',
+  尔: '爾',
+  尝: '嘗',
+  层: '層',
+  属: '屬',
+  岁: '歲',
+  岛: '島',
+  州: '州',
+  工: '工',
+  币: '幣',
+  师: '師',
+  帐: '帳',
+  带: '帶',
+  帮: '幫',
+  干: '乾',
+  并: '並',
+  广: '廣',
+  庆: '慶',
+  库: '庫',
+  应: '應',
+  废: '廢',
+  开: '開',
+  异: '異',
+  弃: '棄',
+  张: '張',
+  强: '強',
+  归: '歸',
+  当: '當',
+  录: '錄',
+  彻: '徹',
+  径: '徑',
+  待: '待',
+  循: '循',
+  忆: '憶',
+  志: '誌',
+  忧: '憂',
+  念: '念',
+  态: '態',
+  总: '總',
+  恢: '恢',
+  息: '息',
+  您: '您',
+  情: '情',
+  想: '想',
+  意: '意',
+  愿: '願',
+  戏: '戲',
+  战: '戰',
+  户: '戶',
+  执: '執',
+  扩: '擴',
+  扫: '掃',
+  扬: '揚',
+  批: '批',
+  找: '找',
+  技: '技',
+  报: '報',
+  护: '護',
+  抽: '抽',
+  担: '擔',
+  拥: '擁',
+  择: '擇',
+  按: '按',
+  挥: '揮',
+  换: '換',
+  损: '損',
+  据: '據',
+  授: '授',
+  掉: '掉',
+  接: '接',
+  控: '控',
+  推: '推',
+  提: '提',
+  插: '插',
+  揭: '揭',
+  搜: '搜',
+  携: '攜',
+  摄: '攝',
+  摘: '摘',
+  播: '播',
+  操: '操',
+  支: '支',
+  收: '收',
+  改: '改',
+  放: '放',
+  效: '效',
+  数: '數',
+  文: '文',
+  断: '斷',
+  新: '新',
+  无: '無',
+  时: '時',
+  明: '明',
+  显: '顯',
+  智: '智',
+  暂: '暫',
+  更: '更',
+  替: '替',
+  术: '術',
+  机: '機',
+  权: '權',
+  条: '條',
+  来: '來',
+  极: '極',
+  构: '構',
+  标: '標',
+  栏: '欄',
+  树: '樹',
+  样: '樣',
+  核: '核',
+  案: '案',
+  档: '檔',
+  检: '檢',
+  楼: '樓',
+  次: '次',
+  款: '款',
+  步: '步',
+  残: '殘',
+  段: '段',
+  毕: '畢',
+  气: '氣',
+  汇: '匯',
+  汉: '漢',
+  没: '沒',
+  法: '法',
+  注: '註',
+  泄: '洩',
+  测: '測',
+  浏: '瀏',
+  消: '消',
+  涉: '涉',
+  涨: '漲',
+  润: '潤',
+  添: '添',
+  清: '清',
+  渠: '渠',
+  渲: '渲',
+  温: '溫',
+  滚: '滾',
+  满: '滿',
+  漏: '漏',
+  演: '演',
+  点: '點',
+  烦: '煩',
+  热: '熱',
+  然: '然',
+  照: '照',
+  爱: '愛',
+  父: '父',
+  片: '片',
+  版: '版',
+  状: '狀',
+  独: '獨',
+  环: '環',
+  现: '現',
+  理: '理',
+  画: '畫',
+  畅: '暢',
+  疗: '療',
+  登: '登',
+  监: '監',
+  盘: '盤',
+  码: '碼',
+  础: '礎',
+  确: '確',
+  碍: '礙',
+  礼: '禮',
+  离: '離',
+  种: '種',
+  称: '稱',
+  稳: '穩',
+  窗: '窗',
+  笔: '筆',
+  签: '簽',
+  简: '簡',
+  算: '算',
+  管: '管',
+  类: '類',
+  粘: '黏',
+  精: '精',
+  系: '系',
+  级: '級',
+  线: '線',
+  组: '組',
+  细: '細',
+  终: '終',
+  经: '經',
+  结: '結',
+  绝: '絕',
+  统: '統',
+  维: '維',
+  缓: '緩',
+  编: '編',
+  缩: '縮',
+  缺: '缺',
+  网: '網',
+  置: '置',
+  联: '聯',
+  聊: '聊',
+  肃: '肅',
+  背: '背',
+  能: '能',
+  脚: '腳',
+  脱: '脫',
+  脑: '腦',
+  自动: '自動',
+  舰: '艦',
+  艺: '藝',
+  节: '節',
+  范: '範',
+  荐: '薦',
+  获: '獲',
+  营: '營',
+  落: '落',
+  著: '著',
+  藏: '藏',
+  虑: '慮',
+  虚: '虛',
+  虽: '雖',
+  行: '行',
+  补: '補',
+  表: '表',
+  装: '裝',
+  规: '規',
+  视: '視',
+  觉: '覺',
+  览: '覽',
+  计: '計',
+  订: '訂',
+  认: '認',
+  议: '議',
+  讯: '訊',
+  记: '記',
+  讲: '講',
+  许: '許',
+  论: '論',
+  设: '設',
+  访: '訪',
+  证: '證',
+  评: '評',
+  识: '識',
+  诉: '訴',
+  试: '試',
+  话: '話',
+  详: '詳',
+  语: '語',
+  误: '誤',
+  请: '請',
+  读: '讀',
+  调: '調',
+  谈: '談',
+  谢: '謝',
+  谷: '谷',
+  账: '帳',
+  负: '負',
+  责: '責',
+  败: '敗',
+  货: '貨',
+  质: '質',
+  资: '資',
+  赃: '贓',
+  起: '起',
+  超: '超',
+  跃: '躍',
+  路: '路',
+  踪: '蹤',
+  车: '車',
+  轮: '輪',
+  软: '軟',
+  载: '載',
+  辑: '輯',
+  输: '輸',
+  边: '邊',
+  达: '達',
+  过: '過',
+  还: '還',
+  这: '這',
+  进: '進',
+  远: '遠',
+  连: '連',
+  迟: '遲',
+  适: '適',
+  选: '選',
+  递: '遞',
+  通: '通',
+  逻: '邏',
+  遗: '遺',
+  遥: '遙',
+  邀: '邀',
+  邮: '郵',
+  部: '部',
+  配: '配',
+  释: '釋',
+  重: '重',
+  针: '針',
+  钥: '鑰',
+  钟: '鐘',
+  钮: '鈕',
+  钱: '錢',
+  链: '鏈',
+  错: '錯',
+  键: '鍵',
+  镜: '鏡',
+  长: '長',
+  门: '門',
+  闭: '閉',
+  间: '間',
+  队: '隊',
+  阶: '階',
+  阳: '陽',
+  阴: '陰',
+  陈: '陳',
+  际: '際',
+  隐: '隱',
+  难: '難',
+  雏: '雛',
+  需: '需',
+  面: '面',
+  页: '頁',
+  项: '項',
+  顺: '順',
+  须: '須',
+  预: '預',
+  题: '題',
+  颜: '顏',
+  风: '風',
+  飞: '飛',
+  馆: '館',
+  验: '驗',
+  高: '高',
+  鱼: '魚',
+  鲜: '鮮',
+  鸟: '鳥',
+  麦: '麥',
+  黄: '黃',
+};
+
+export function toTraditionalChinese(value: string): string {
+  let converted = value;
+  for (const [source, target] of SIMPLIFIED_TO_TRADITIONAL_PHRASES) {
+    converted = converted.split(source).join(target);
+  }
+  return Array.from(converted)
+    .map((char) => SIMPLIFIED_TO_TRADITIONAL_CHARS[char] ?? char)
+    .join('');
 }

app-instance/frontend/lib/task-timeline-view.test.ts

@@ -40,9 +40,11 @@ describe('buildTaskTimelineView', () => {
     const view = buildTaskTimelineView({
       task: task(),
       liveEvents,
+      locale: 'en-US',
     });
 
     expect(view?.cards.map((card) => card.type)).toEqual(['task_created', 'plan']);
+    expect(view?.cards.map((card) => card.title)).toEqual(['Task created', 'Execution plan']);
     expect(view?.process.events.map((event) => event.event_id)).toEqual(['plan']);
   });
 

app-instance/frontend/lib/task-timeline-view.ts

@@ -1,9 +1,11 @@
 import { selectTaskProcess, type SelectTaskProcessInput, type TaskProcessSelection } from '@/lib/task-process';
 import { buildTaskTimelineCards } from '@/lib/task-timeline';
+import type { AppLocale } from '@/lib/i18n/core';
 import type { BackendTask, TaskTimelineCard } from '@/types';
 
 export type BuildTaskTimelineViewInput = Omit<SelectTaskProcessInput, 'task'> & {
   task: BackendTask | null;
+  locale?: AppLocale | string;
 };
 
 export type TaskTimelineView = {
@@ -16,6 +18,7 @@ export function buildTaskTimelineView({
   liveRuns,
   liveEvents,
   liveArtifacts,
+  locale,
 }: BuildTaskTimelineViewInput): TaskTimelineView | null {
   if (!task) return null;
 
@@ -32,6 +35,7 @@ export function buildTaskTimelineView({
       processRuns: process.runs,
       processEvents: process.events,
       processArtifacts: process.artifacts,
+      locale,
     }),
   };
 }

app-instance/frontend/lib/task-timeline.test.ts

@@ -143,6 +143,48 @@ describe('buildTaskTimelineCards', () => {
     expect(cards[6].relatedArtifactIds).toEqual(['artifact-summary']);
   });
 
+  it('localizes generated milestone titles for English and Traditional Chinese', () => {
+    const task = makeTask();
+    const processEvents: ProcessEvent[] = [
+      {
+        event_id: 'evt-plan',
+        run_id: 'run-main',
+        parent_run_id: null,
+        kind: 'task_planned',
+        actor_type: 'agent',
+        actor_id: 'planner',
+        actor_name: 'Task Planner',
+        text: 'Plan created.',
+        created_at: '2026-05-26T10:01:00.000Z',
+      },
+      {
+        event_id: 'evt-tool-start',
+        run_id: 'run-main',
+        parent_run_id: null,
+        kind: 'tool_call_started',
+        actor_type: 'mcp',
+        actor_id: 'user_files_list',
+        actor_name: 'user_files_list',
+        text: 'Calling tool: user_files_list.',
+        created_at: '2026-05-26T10:02:00.000Z',
+      },
+    ];
+
+    const englishCards = buildTaskTimelineCards({ task, processEvents, locale: 'en-US' });
+    const traditionalCards = buildTaskTimelineCards({ task, processEvents, locale: 'zh-Hant' });
+
+    expect(englishCards.map((card) => card.title)).toEqual([
+      'Task created',
+      'Execution plan',
+      'Calling tool: user_files_list',
+    ]);
+    expect(traditionalCards.map((card) => card.title)).toEqual([
+      '任務已創建',
+      '執行計劃',
+      '調用工具：user_files_list',
+    ]);
+  });
+
   it('appends result and acceptance cards for closed tasks with feedback', () => {
     const task = makeTask({
       is_open: false,

app-instance/frontend/lib/task-timeline.ts

@@ -6,12 +6,14 @@ import type {
   TaskTimelineCard,
   TaskTimelineCardType,
 } from '@/types';
+import { getCurrentAppLocale, pickAppText, type AppLocale } from '@/lib/i18n/core';
 
 export type BuildTaskTimelineCardsInput = {
   task: BackendTask;
   processRuns?: ProcessRun[];
   processEvents?: ProcessEvent[];
   processArtifacts?: ProcessArtifact[];
+  locale?: AppLocale | string;
 };
 
 const TIMELINE_CARD_TYPES = new Set<TaskTimelineCardType>([
@@ -110,36 +112,40 @@ function cardTypeForEvent(event: ProcessEvent): TaskTimelineCardType | null {
   }
 }
 
-function titleForCard(type: TaskTimelineCardType, actorName?: string): string {
+function titleForCard(type: TaskTimelineCardType, actorName?: string, locale: AppLocale | string = getCurrentAppLocale()): string {
   switch (type) {
     case 'task_created':
-      return '任务已创建';
+      return pickAppText(locale, '任务已创建', 'Task created');
     case 'plan':
-      return '执行计划';
+      return pickAppText(locale, '执行计划', 'Execution plan');
     case 'skill':
-      return '选择 Skill';
+      return pickAppText(locale, '选择 Skill', 'Skill selected');
     case 'tool_call':
-      return actorName ? `调用工具：${actorName}` : '调用工具';
+      return actorName
+        ? pickAppText(locale, `调用工具：${actorName}`, `Calling tool: ${actorName}`)
+        : pickAppText(locale, '调用工具', 'Tool call');
     case 'tool_result':
-      return actorName ? `工具结果：${actorName}` : '工具结果';
+      return actorName
+        ? pickAppText(locale, `工具结果：${actorName}`, `Tool result: ${actorName}`)
+        : pickAppText(locale, '工具结果', 'Tool result');
     case 'next_step':
-      return '下一步';
+      return pickAppText(locale, '下一步', 'Next step');
     case 'agent_team':
-      return '启动 Agent Team';
+      return pickAppText(locale, '启动 Agent Team', 'Agent team started');
     case 'agent_progress':
-      return actorName || 'Agent 进展';
+      return actorName || pickAppText(locale, 'Agent 进展', 'Agent progress');
     case 'agent_handoff':
-      return 'Agent 交接';
+      return pickAppText(locale, 'Agent 交接', 'Agent handoff');
     case 'artifact':
-      return '生成产物';
+      return pickAppText(locale, '生成产物', 'Artifact generated');
     case 'error':
-      return '执行遇到问题';
+      return pickAppText(locale, '执行遇到问题', 'Execution issue');
     case 'result':
-      return '本轮结果';
+      return pickAppText(locale, '本轮结果', 'Run result');
     case 'result_history':
-      return '历史结果版本';
+      return pickAppText(locale, '历史结果版本', 'Previous result versions');
     case 'acceptance':
-      return '任务验收';
+      return pickAppText(locale, '任务验收', 'Task acceptance');
   }
 }
 
@@ -286,7 +292,12 @@ function buildToolResultStatusByCall(processEvents: ProcessEvent[]): Map<string,
   return statuses;
 }
 
-function buildResultHistoryCard(task: BackendTask, resultCards: TaskTimelineCard[], acceptanceCards: TaskTimelineCard[]): TaskTimelineCard {
+function buildResultHistoryCard(
+  task: BackendTask,
+  resultCards: TaskTimelineCard[],
+  acceptanceCards: TaskTimelineCard[],
+  locale: AppLocale | string,
+): TaskTimelineCard {
   const versions = resultCards.map((resultCard) => {
     const acceptanceCard = acceptanceCards
       .filter((card) => card.runId === resultCard.runId)
@@ -307,14 +318,18 @@ function buildResultHistoryCard(task: BackendTask, resultCards: TaskTimelineCard
     id: `${task.task_id}:result-history`,
     taskId: task.task_id,
     type: 'result_history',
-    title: titleForCard('result_history'),
-    summary: `${resultCards.length} 历史结果版本`,
+    title: titleForCard('result_history', undefined, locale),
+    summary: pickAppText(
+      locale,
+      `${resultCards.length} 历史结果版本`,
+      `${resultCards.length} previous result ${resultCards.length === 1 ? 'version' : 'versions'}`,
+    ),
     createdAt: resultCards[0]?.createdAt ?? task.created_at,
     details: { versions },
   };
 }
 
-function collapseHistoricalResults(task: BackendTask, cards: TaskTimelineCard[]): TaskTimelineCard[] {
+function collapseHistoricalResults(task: BackendTask, cards: TaskTimelineCard[], locale: AppLocale | string): TaskTimelineCard[] {
   const resultCards = cards.filter((card) => card.type === 'result');
   if (resultCards.length <= 1) return cards;
 
@@ -334,7 +349,7 @@ function collapseHistoricalResults(task: BackendTask, cards: TaskTimelineCard[])
     .filter((card) => card.type === 'acceptance' && oldRunIds.has(card.runId))
     .sort((a, b) => cardTime(a) - cardTime(b));
   const foldedIds = new Set([...oldResults, ...oldAcceptances].map((card) => card.id));
-  const historyCard = buildResultHistoryCard(task, oldResults, oldAcceptances);
+  const historyCard = buildResultHistoryCard(task, oldResults, oldAcceptances, locale);
   const firstOldResultIndex = cards.findIndex((card) => card.id === oldResults[0].id);
   const output: TaskTimelineCard[] = [];
 
@@ -352,6 +367,7 @@ function collapseHistoricalResults(task: BackendTask, cards: TaskTimelineCard[])
 
 export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): TaskTimelineCard[] {
   const { task } = input;
+  const locale = input.locale ?? getCurrentAppLocale();
   const processRuns = input.processRuns ?? task.process_runs ?? [];
   const processEvents = input.processEvents ?? task.process_events ?? [];
   const processArtifacts = input.processArtifacts ?? task.process_artifacts ?? [];
@@ -365,7 +381,7 @@ export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): Task
       id: `${task.task_id}:created`,
       taskId: task.task_id,
       type: 'task_created',
-      title: titleForCard('task_created'),
+      title: titleForCard('task_created', undefined, locale),
       summary: firstString(task.short_title, task.description, task.goal),
       actorName: task.creator,
       status: task.status,
@@ -396,7 +412,7 @@ export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): Task
       runId: event.run_id,
       parentRunId: event.parent_run_id,
       type,
-      title: titleForCard(type, event.actor_name),
+      title: titleForCard(type, event.actor_name, locale),
       summary: type === 'result' ? resultSummaryForEvent(task, event) : summaryForEvent(event),
       actorName: event.actor_name,
       status:
@@ -418,7 +434,7 @@ export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): Task
       runId: run.run_id,
       parentRunId: run.parent_run_id,
       type: 'agent_progress',
-      title: titleForCard('agent_progress', run.actor_name),
+      title: titleForCard('agent_progress', run.actor_name, locale),
       summary: firstString(run.summary, run.title),
       actorName: run.actor_name,
       status: run.status,
@@ -435,7 +451,7 @@ export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): Task
       runId: artifact.run_id,
       parentRunId: run?.parent_run_id,
       type: 'artifact',
-      title: titleForCard('artifact'),
+      title: titleForCard('artifact', undefined, locale),
       summary: firstString(artifact.title),
       actorName: artifact.actor_name,
       createdAt: artifact.created_at,
@@ -454,7 +470,7 @@ export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): Task
       taskId: task.task_id,
       runId: lastItem(task.run_ids),
       type: 'result',
-      title: titleForCard('result'),
+      title: titleForCard('result', undefined, locale),
       summary: fallbackResultSummary(task),
       status: task.status,
       createdAt: task.closed_at ?? task.updated_at ?? task.created_at,
@@ -473,7 +489,7 @@ export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): Task
       taskId: task.task_id,
       runId,
       type: 'acceptance',
-      title: titleForCard('acceptance'),
+      title: titleForCard('acceptance', undefined, locale),
       summary: feedbackSummary(feedback),
       status: firstString(feedback.acceptance_type),
       createdAt,
@@ -486,5 +502,5 @@ export function buildTaskTimelineCards(input: BuildTaskTimelineCardsInput): Task
     .sort(compareCardsByCreatedAt)
     .map(({ card }) => card);
 
-  return collapseHistoricalResults(task, sortedCards);
+  return collapseHistoricalResults(task, sortedCards, locale);
 }