一般設定の追加(UI/Ollama設定) settings.jsonに設定を保存 UIから言語設定対応 Ollama設定でシステムプロンプト, temperature, コンテキスト長などのパラメータを設定可能

13 files changed, 832 insertions, 21 deletions

diff --git a/README.md b/README.md
index e259fb4..219d716 100644
--- a/README.md
+++ b/README.md
@@ -83,6 +83,12 @@ ollama-web
 
 UI 文言と LLM プロンプトは、それぞれ `src/ollama_web/i18n/messages/` と `src/ollama_web/prompts/` の JSON ファイルで管理されています。既定は日本語（`ja`）です。新しい言語を追加する場合は、同じディレクトリに `{lang}.json` を作成し、`OLLAMA_WEB_LANGUAGE` をその言語コードに設定してください。
 
+### 一般設定
+
+ブラウザの左ペイン下部にある「一般設定」から、表示言語、システムプロンプト、Ollama の生成Optionsを変更できます。設定は `OLLAMA_WEB_DATA_DIR/settings.json` に保存され、このデータディレクトリを利用する全セッションで共有されます。
+
+保存済みの表示言語は `OLLAMA_WEB_LANGUAGE` より優先されます。システムプロンプトは内蔵のTool用プロンプトの後に追加され、空欄の詳細Optionsと乱数モードの `seed` はOllamaへ送信されません。
+
 ### MCP サーバー設定
 
 `data/mcpServers.json` に接続先 MCP サーバーを記述します。ブラウザの左ペイン下部「MCP設定」からも編集・保存できます。
diff --git a/src/ollama_web/app.py b/src/ollama_web/app.py
index c7477c8..701cc3c 100644
--- a/src/ollama_web/app.py
+++ b/src/ollama_web/app.py
@@ -9,7 +9,6 @@ from typing import Any
 from starlette.applications import Starlette
 from starlette.middleware import Middleware
 from starlette.middleware.cors import CORSMiddleware
-from starlette.requests import Request
 from starlette.responses import Response
 from starlette.routing import Mount, Route
 from starlette.staticfiles import StaticFiles
@@ -23,6 +22,7 @@ from .routes import mcp as mcp_route
 from .routes import models as models_route
 from .routes import pages as pages_route
 from .routes import sessions as sessions_route
+from .routes import settings_route
 from .sessions import SessionStore
 
 
@@ -69,6 +69,18 @@ def create_app() -> Starlette:
             name="model_capabilities",
         ),
         Route("/api/health", models_route.health, methods=["GET"], name="health"),
+        Route(
+            "/api/settings",
+            settings_route.get_settings,
+            methods=["GET"],
+            name="settings",
+        ),
+        Route(
+            "/api/settings",
+            settings_route.put_settings,
+            methods=["PUT"],
+            name="settings_update",
+        ),
         Route("/api/sessions", sessions_route.list_sessions, methods=["GET"], name="list_sessions"),
         Route(
             "/api/sessions",
@@ -122,7 +134,7 @@ def create_app() -> Starlette:
             Middleware(
                 CORSMiddleware,
                 allow_origins=settings.allowed_origins,
-                allow_methods=["GET", "POST", "DELETE"],
+                allow_methods=["GET", "POST", "PUT", "DELETE"],
                 allow_headers=["Content-Type", "X-CSRF-Token"],
                 allow_credentials=True,
             )
@@ -135,4 +147,4 @@ def create_app() -> Starlette:
     return app
 
 
-app = create_app()
\ No newline at end of file
+app = create_app()
diff --git a/src/ollama_web/i18n/messages/en.json b/src/ollama_web/i18n/messages/en.json
index 2195c6e..8bf3913 100644
--- a/src/ollama_web/i18n/messages/en.json
+++ b/src/ollama_web/i18n/messages/en.json
@@ -4,12 +4,14 @@
     "stop": "Stop",
     "clear": "Clear",
     "save": "Save",
-    "delete": "Delete"
+    "delete": "Delete",
+    "close": "Close"
   },
   "chat": {
     "sessions": "Sessions",
     "new_session": "New session",
     "session_list": "Session list",
+    "general_settings": "General Settings",
     "mcp_settings": "MCP Settings",
     "model_label": "Model:",
     "attach_file": "Attach file",
@@ -96,5 +98,41 @@
     "save_failed": "Failed to save: {error}",
     "saved": "MCP settings saved",
     "save_error": "Failed to save MCP settings"
+  },
+  "settings": {
+    "back": "Back",
+    "general": {
+      "title": "General Settings",
+      "description": "Choose the settings you want to change."
+    },
+    "ui": {
+      "title": "UI Settings",
+      "description": "Change the display language.",
+      "language": "Language",
+      "reload_notice": "The page reloads after saving to apply the change."
+    },
+    "ollama": {
+      "title": "Ollama Settings",
+      "description": "Change the system prompt and generation options.",
+      "system_prompt": "System prompt",
+      "system_prompt_placeholder": "Instructions appended after the built-in tool prompt",
+      "temperature": "temperature",
+      "num_ctx": "Context length",
+      "seed": "seed",
+      "seed_mode": "Seed mode",
+      "seed_random": "Random (not specified)",
+      "seed_fixed": "Fixed value",
+      "seed_value": "Fixed seed value",
+      "advanced": "Advanced settings",
+      "blank_omitted": "Blank options are not sent to Ollama.",
+      "stop_placeholder": "Enter one stop sequence per line"
+    },
+    "messages": {
+      "load_failed": "Failed to load settings.",
+      "save_failed": "Failed to save settings: {error}",
+      "saved": "Settings saved.",
+      "invalid_integer": "Enter an integer.",
+      "invalid_number": "Enter a number."
+    }
   }
 }
diff --git a/src/ollama_web/i18n/messages/ja.json b/src/ollama_web/i18n/messages/ja.json
index 9d42f85..12a9e4b 100644
--- a/src/ollama_web/i18n/messages/ja.json
+++ b/src/ollama_web/i18n/messages/ja.json
@@ -4,12 +4,14 @@
     "stop": "停止",
     "clear": "クリア",
     "save": "保存",
-    "delete": "削除"
+    "delete": "削除",
+    "close": "閉じる"
   },
   "chat": {
     "sessions": "セッション",
     "new_session": "新規セッション",
     "session_list": "セッション一覧",
+    "general_settings": "一般設定",
     "mcp_settings": "MCP設定",
     "model_label": "モデル:",
     "attach_file": "ファイルを添付",
@@ -96,5 +98,41 @@
     "save_failed": "保存に失敗しました: {error}",
     "saved": "MCP設定を保存しました",
     "save_error": "MCP設定の保存に失敗しました"
+  },
+  "settings": {
+    "back": "戻る",
+    "general": {
+      "title": "一般設定",
+      "description": "変更する設定を選択してください。"
+    },
+    "ui": {
+      "title": "UI設定",
+      "description": "表示言語を変更します。",
+      "language": "言語",
+      "reload_notice": "保存後、変更を反映するためページを再読み込みします。"
+    },
+    "ollama": {
+      "title": "Ollama設定",
+      "description": "システムプロンプトと生成Optionsを変更します。",
+      "system_prompt": "システムプロンプト",
+      "system_prompt_placeholder": "内蔵ツールプロンプトの後に追加する指示",
+      "temperature": "temperature",
+      "num_ctx": "コンテキスト長",
+      "seed": "seed",
+      "seed_mode": "seed方式",
+      "seed_random": "乱数（指定しない）",
+      "seed_fixed": "固定値",
+      "seed_value": "seed固定値",
+      "advanced": "詳細設定",
+      "blank_omitted": "空欄の項目はOllamaへ送信されません。",
+      "stop_placeholder": "停止文字列を1行に1件入力"
+    },
+    "messages": {
+      "load_failed": "設定の読み込みに失敗しました。",
+      "save_failed": "設定の保存に失敗しました: {error}",
+      "saved": "設定を保存しました。",
+      "invalid_integer": "整数を入力してください。",
+      "invalid_number": "数値を入力してください。"
+    }
   }
 }
diff --git a/src/ollama_web/llm.py b/src/ollama_web/llm.py
index 80e0ba6..4e11122 100644
--- a/src/ollama_web/llm.py
+++ b/src/ollama_web/llm.py
@@ -10,7 +10,6 @@ from typing import Any, cast
 import ollama
 from ollama import Message
 
-
 from .config import settings
 from .i18n import t
 from .mcp import redact_secrets
@@ -186,6 +185,8 @@ def chat_with_tools(
     registry: ToolRegistry | None = None,
     host: str | None = None,
     capabilities: set[str] | None = None,
+    options: dict[str, Any] | None = None,
+    language: str | None = None,
 ) -> Iterator[dict[str, Any]]:
     """Run a multi-round tool-calling chat and yield progress events.
 
@@ -234,6 +235,7 @@ def chat_with_tools(
                 messages=messages,
                 tools=effective_tools,
                 think=effective_think,
+                options=options or None,
                 stream=False,
             )
         except Exception as exc:  # noqa: BLE001
@@ -292,12 +294,12 @@ def chat_with_tools(
     )
     yield {
         "type": "status",
-        "message": t("status.tool_limit_reached"),
+        "message": t("status.tool_limit_reached", lang=language),
     }
     messages.append(
         Message(
             role="user",
-            content=get_prompt("tool_limit_instruction"),
+            content=get_prompt("tool_limit_instruction", lang=language),
         )
     )
     try:
@@ -306,6 +308,7 @@ def chat_with_tools(
             messages=messages,
             tools=effective_tools,
             think=effective_think,
+            options=options or None,
             stream=False,
         )
     except Exception as exc:  # noqa: BLE001
@@ -341,6 +344,8 @@ def stream_chat_with_tools(
     registry: ToolRegistry | None = None,
     host: str | None = None,
     capabilities: set[str] | None = None,
+    options: dict[str, Any] | None = None,
+    language: str | None = None,
 ) -> Iterator[dict[str, Any]]:
     """Run a tool-calling chat loop and yield real streaming events from ollama.
 
@@ -386,6 +391,7 @@ def stream_chat_with_tools(
                 messages=messages,
                 tools=effective_tools,
                 think=effective_think,
+                options=options or None,
                 stream=True,
             )
         except Exception as exc:  # noqa: BLE001
@@ -487,12 +493,12 @@ def stream_chat_with_tools(
     )
     yield {
         "type": "status",
-        "message": t("status.tool_limit_reached"),
+        "message": t("status.tool_limit_reached", lang=language),
     }
     messages.append(
         Message(
             role="user",
-            content=get_prompt("tool_limit_instruction"),
+            content=get_prompt("tool_limit_instruction", lang=language),
         )
     )
     t0 = time.time()
@@ -502,6 +508,7 @@ def stream_chat_with_tools(
             messages=messages,
             tools=effective_tools,
             think=effective_think,
+            options=options or None,
             stream=True,
         )
     except Exception as exc:  # noqa: BLE001
@@ -529,12 +536,21 @@ async def astream_chat_with_tools(
     registry: ToolRegistry | None = None,
     host: str | None = None,
     capabilities: set[str] | None = None,
+    options: dict[str, Any] | None = None,
+    language: str | None = None,
 ) -> AsyncIterator[dict[str, Any]]:
     """Async wrapper that yields events from ``stream_chat_with_tools``."""
     import anyio
 
     gen = stream_chat_with_tools(
-        messages, model, think=think, registry=registry, host=host, capabilities=capabilities
+        messages,
+        model,
+        think=think,
+        registry=registry,
+        host=host,
+        capabilities=capabilities,
+        options=options,
+        language=language,
     )
 
     def _next() -> dict[str, Any] | None:
diff --git a/src/ollama_web/routes/chat.py b/src/ollama_web/routes/chat.py
index 30794be..c8cbcff 100644
--- a/src/ollama_web/routes/chat.py
+++ b/src/ollama_web/routes/chat.py
@@ -20,6 +20,7 @@ from ..i18n import t
 from ..mcp import collect_mcp_tools, make_mcp_executor
 from ..prompts import get_prompt
 from ..sessions import SessionStore, is_valid_id
+from ..settings_store import load_app_settings
 from ..tools.fetch import pop_fetched_files
 from ..tools.helper.image import resize_image
 from ..tools.registry import ToolRegistry, default_registry
@@ -27,17 +28,18 @@ from ..tools.registry import ToolRegistry, default_registry
 logger = logging.getLogger("ollama_web.chat")
 
 
-# System prompt injected when tools are enabled. Encourages the model to use
-# tools iteratively rather than firing many searches at once.
-_TOOL_SYSTEM_PROMPT = get_prompt("tool_system")
-
-
 def _limit_text(text: str, limit: int) -> str:
     if len(text) <= limit:
         return text
     return text[:limit] + "\n…[truncated]"
 
 
+def _compose_system_prompt(language: str, custom_prompt: str) -> str:
+    """Combine the localized built-in tool prompt with the user prompt."""
+    tool_prompt = get_prompt("tool_system", lang=language)
+    return f"{tool_prompt}\n\n{custom_prompt}" if custom_prompt else tool_prompt
+
+
 def _parse_messages(raw: list[dict[str, Any]]) -> list[Message]:
     """Convert raw JSON message dicts into ``ollama.Message`` objects."""
     out: list[Message] = []
@@ -153,6 +155,13 @@ async def _chat_event_stream(
     """Core chat loop yielding events. Exceptions are converted to SSE error events."""
     model = payload.get("model") or request.app.state.settings.default_model
     think = payload.get("think")
+    runtime_settings = request.app.state.settings
+    app_settings = load_app_settings(runtime_settings.data_dir, runtime_settings.language)
+    language = str(app_settings["ui"]["language"])
+    ollama_settings = app_settings["ollama"]
+    ollama_options = dict(ollama_settings["options"])
+    custom_prompt = str(ollama_settings["system_prompt"])
+    system_prompt = _compose_system_prompt(language, custom_prompt)
 
     store: SessionStore = request.app.state.session_store
     file_ids: list[str] = [
@@ -202,7 +211,7 @@ async def _chat_event_stream(
         # are available. Avoid duplicate injection if the session already has
         # a system message.
         if not any(getattr(m, "role", None) == "system" for m in messages):
-            messages.insert(0, Message(role="system", content=_TOOL_SYSTEM_PROMPT))
+            messages.insert(0, Message(role="system", content=system_prompt))
 
         host = request.app.state.settings.ollama_host
 
@@ -238,7 +247,7 @@ async def _chat_event_stream(
 
         async for event in llm.astream_chat_with_tools(
             messages, model, think=think, host=host, registry=registry,
-            capabilities=capabilities,
+            capabilities=capabilities, options=ollama_options, language=language,
         ):
             if event.get("type") == "delta":
                 assistant_text = _limit_text(
@@ -255,7 +264,7 @@ async def _chat_event_stream(
         # and re-renders in the chat pane.
         assistant_text = (
             f"[ERROR] {error_msg}\n\n"
-            f"{t('errors.vision_model_required')}"
+            f"{t('errors.vision_model_required', lang=language)}"
         )
 
     finally:
diff --git a/src/ollama_web/routes/pages.py b/src/ollama_web/routes/pages.py
index 45a3a01..7bf81e1 100644
--- a/src/ollama_web/routes/pages.py
+++ b/src/ollama_web/routes/pages.py
@@ -10,24 +10,34 @@ from starlette.templating import Jinja2Templates
 
 from ollama_web import llm
 from ollama_web.i18n import get_messages, t
+from ollama_web.settings_store import load_app_settings
 
 _TEMPLATES_DIR = Path(__file__).resolve().parent.parent / "templates"
 templates = Jinja2Templates(directory=str(_TEMPLATES_DIR))
 templates.env.globals["t"] = t
 
 
+def _page_i18n(request: Request) -> tuple[str, dict[str, object]]:
+    runtime = request.app.state.settings
+    app_settings = load_app_settings(runtime.data_dir, runtime.language)
+    language = str(app_settings["ui"]["language"])
+    return language, get_messages(language)
+
+
 async def index(request: Request) -> Response:
     """Render the chat page with the available model list."""
     host = request.app.state.settings.ollama_host
     models = llm.list_models(host=host)
     default_model = request.app.state.settings.default_model
+    language, messages = _page_i18n(request)
     return templates.TemplateResponse(
         request,
         "index.html",
         {
             "models": models,
             "default_model": default_model,
-            "messages": get_messages(),
+            "messages": messages,
+            "t": lambda key, fallback=None: t(key, lang=language, fallback=fallback),
         },
         media_type="text/html; charset=utf-8",
         headers={"Cache-Control": "no-store, no-cache, must-revalidate, max-age=0"},
@@ -36,11 +46,13 @@ async def index(request: Request) -> Response:
 
 async def login(request: Request) -> Response:
     """Render the PIN login page."""
+    language, messages = _page_i18n(request)
     return templates.TemplateResponse(
         request,
         "login.html",
         {
-            "messages": get_messages(),
+            "messages": messages,
+            "t": lambda key, fallback=None: t(key, lang=language, fallback=fallback),
         },
         media_type="text/html; charset=utf-8",
         headers={"Cache-Control": "no-store, no-cache, must-revalidate, max-age=0"},
diff --git a/src/ollama_web/routes/settings_route.py b/src/ollama_web/routes/settings_route.py
new file mode 100644
index 0000000..560f8d9
--- /dev/null
+++ b/src/ollama_web/routes/settings_route.py
@@ -0,0 +1,30 @@
+"""Application settings API endpoints."""
+
+from __future__ import annotations
+
+from starlette.requests import Request
+from starlette.responses import JSONResponse
+
+from ..settings_store import (
+    SettingsValidationError,
+    load_app_settings,
+    save_app_settings,
+)
+
+
+async def get_settings(request: Request) -> JSONResponse:
+    """GET /api/settings: return effective persisted application settings."""
+    runtime = request.app.state.settings
+    return JSONResponse(load_app_settings(runtime.data_dir, runtime.language))
+
+
+async def put_settings(request: Request) -> JSONResponse:
+    """PUT /api/settings: validate and persist application settings."""
+    try:
+        body = await request.json()
+        cleaned = save_app_settings(request.app.state.settings.data_dir, body)
+    except SettingsValidationError as exc:
+        return JSONResponse({"error": str(exc)}, status_code=400)
+    except Exception:  # noqa: BLE001
+        return JSONResponse({"error": "Invalid JSON body"}, status_code=400)
+    return JSONResponse(cleaned)
diff --git a/src/ollama_web/settings_store.py b/src/ollama_web/settings_store.py
new file mode 100644
index 0000000..6cdd022
--- /dev/null
+++ b/src/ollama_web/settings_store.py
@@ -0,0 +1,166 @@
+"""Persistent application settings stored under ``OLLAMA_WEB_DATA_DIR``."""
+
+from __future__ import annotations
+
+import json
+import math
+import threading
+from copy import deepcopy
+from pathlib import Path
+from typing import Any
+
+NUM_CTX_VALUES = (4096, 8192, 16384, 32768, 65536, 131072, 262144)
+INTEGER_OPTIONS = {
+    "num_ctx",
+    "num_keep",
+    "seed",
+    "num_predict",
+    "top_k",
+    "repeat_last_n",
+    "mirostat",
+}
+FLOAT_OPTIONS = {
+    "temperature",
+    "top_p",
+    "min_p",
+    "typical_p",
+    "tfs_z",
+    "repeat_penalty",
+    "presence_penalty",
+    "frequency_penalty",
+    "mirostat_tau",
+    "mirostat_eta",
+}
+OPTION_KEYS = INTEGER_OPTIONS | FLOAT_OPTIONS | {"stop"}
+SUPPORTED_LANGUAGES = {"ja", "en"}
+
+_LOCK = threading.RLock()
+
+
+class SettingsValidationError(ValueError):
+    """Raised when persisted settings do not match the public schema."""
+
+
+def default_app_settings(language: str = "ja") -> dict[str, Any]:
+    """Return a fresh settings object with required slider defaults."""
+    if language not in SUPPORTED_LANGUAGES:
+        language = "ja"
+    return {
+        "ui": {"language": language},
+        "ollama": {
+            "system_prompt": "",
+            "options": {"temperature": 0.8, "num_ctx": 8192},
+        },
+    }
+
+
+def settings_file(data_dir: str | Path) -> Path:
+    return Path(data_dir).resolve() / "settings.json"
+
+
+def _require_keys(value: dict[str, Any], allowed: set[str], where: str) -> None:
+    unknown = set(value) - allowed
+    if unknown:
+        raise SettingsValidationError(
+            f"Unknown {where} field(s): {', '.join(sorted(unknown))}"
+        )
+
+
+def _validate_options(raw: Any) -> dict[str, Any]:
+    if not isinstance(raw, dict):
+        raise SettingsValidationError("ollama.options must be an object")
+    _require_keys(raw, OPTION_KEYS, "option")
+
+    cleaned: dict[str, Any] = {}
+    for key, value in raw.items():
+        if key in INTEGER_OPTIONS:
+            if isinstance(value, bool) or not isinstance(value, int):
+                raise SettingsValidationError(f"ollama.options.{key} must be an integer")
+            cleaned[key] = value
+        elif key in FLOAT_OPTIONS:
+            if isinstance(value, bool) or not isinstance(value, (int, float)):
+                raise SettingsValidationError(f"ollama.options.{key} must be a number")
+            number = float(value)
+            if not math.isfinite(number):
+                raise SettingsValidationError(f"ollama.options.{key} must be finite")
+            cleaned[key] = number
+        elif key == "stop":
+            if not isinstance(value, list) or not all(
+                isinstance(item, str) and item for item in value
+            ):
+                raise SettingsValidationError(
+                    "ollama.options.stop must be an array of non-empty strings"
+                )
+            cleaned[key] = list(value)
+
+    if "temperature" not in cleaned or not 0 <= cleaned["temperature"] <= 2:
+        raise SettingsValidationError("ollama.options.temperature must be between 0 and 2")
+    if cleaned.get("num_ctx") not in NUM_CTX_VALUES:
+        raise SettingsValidationError("ollama.options.num_ctx is not an allowed context size")
+    return cleaned
+
+
+def validate_app_settings(raw: Any) -> dict[str, Any]:
+    """Validate and normalize the settings API payload."""
+    if not isinstance(raw, dict):
+        raise SettingsValidationError("Settings must be an object")
+    _require_keys(raw, {"ui", "ollama"}, "settings")
+    if set(raw) != {"ui", "ollama"}:
+        raise SettingsValidationError("Settings must contain ui and ollama")
+
+    ui = raw["ui"]
+    if not isinstance(ui, dict):
+        raise SettingsValidationError("ui must be an object")
+    _require_keys(ui, {"language"}, "ui")
+    language = ui.get("language")
+    if language not in SUPPORTED_LANGUAGES:
+        raise SettingsValidationError("ui.language must be ja or en")
+
+    ollama = raw["ollama"]
+    if not isinstance(ollama, dict):
+        raise SettingsValidationError("ollama must be an object")
+    _require_keys(ollama, {"system_prompt", "options"}, "ollama")
+    if set(ollama) != {"system_prompt", "options"}:
+        raise SettingsValidationError("ollama must contain system_prompt and options")
+    system_prompt = ollama["system_prompt"]
+    if not isinstance(system_prompt, str):
+        raise SettingsValidationError("ollama.system_prompt must be a string")
+    if len(system_prompt) > 20_000:
+        raise SettingsValidationError("ollama.system_prompt is too long")
+
+    return {
+        "ui": {"language": language},
+        "ollama": {
+            "system_prompt": system_prompt,
+            "options": _validate_options(ollama["options"]),
+        },
+    }
+
+
+def load_app_settings(data_dir: str | Path, default_language: str = "ja") -> dict[str, Any]:
+    """Load validated settings, falling back safely when absent or malformed."""
+    default = default_app_settings(default_language)
+    path = settings_file(data_dir)
+    with _LOCK:
+        if not path.exists():
+            return default
+        try:
+            raw = json.loads(path.read_text(encoding="utf-8"))
+            return validate_app_settings(raw)
+        except (OSError, json.JSONDecodeError, SettingsValidationError):
+            return default
+
+
+def save_app_settings(data_dir: str | Path, raw: Any) -> dict[str, Any]:
+    """Validate and atomically persist settings, returning the normalized value."""
+    cleaned = validate_app_settings(raw)
+    path = settings_file(data_dir)
+    temp_path = path.with_suffix(".json.tmp")
+    with _LOCK:
+        path.parent.mkdir(parents=True, exist_ok=True)
+        temp_path.write_text(
+            json.dumps(cleaned, ensure_ascii=False, indent=2) + "\n",
+            encoding="utf-8",
+        )
+        temp_path.replace(path)
+    return deepcopy(cleaned)
diff --git a/src/ollama_web/static/settings-actions.js b/src/ollama_web/static/settings-actions.js
new file mode 100644
index 0000000..3411c54
--- /dev/null
+++ b/src/ollama_web/static/settings-actions.js
@@ -0,0 +1,151 @@
+"use strict";
+(function () {
+  const $ = (id) => document.getElementById(id);
+  const modal = $("settings-modal");
+  const screens = [...document.querySelectorAll("[data-settings-screen]")];
+  const advanced = [...document.querySelectorAll("[data-option]")];
+  const ctxValues = [4096, 8192, 16384, 32768, 65536, 131072, 262144];
+  const ctxLabels = ["4k", "8k", "16k", "32k", "64k", "128k", "256k"];
+  let screen = "general";
+
+  function cookie(name) {
+    const found = document.cookie.split(";").map((v) => v.trim())
+      .find((v) => v.startsWith(`${name}=`));
+    return found ? decodeURIComponent(found.slice(name.length + 1)) : "";
+  }
+  async function request(url, options = {}) {
+    const headers = { ...(options.headers || {}) };
+    if ((options.method || "GET").toUpperCase() !== "GET") {
+      headers["X-CSRF-Token"] = cookie("ollama_web_csrf");
+    }
+    const response = await fetch(url, { ...options, headers });
+    if (response.status === 401) location.assign(`/login?next=${encodeURIComponent(location.pathname)}`);
+    return response;
+  }
+  function status(message, error = false) {
+    $("settings-status").textContent = message;
+    $("settings-status").classList.toggle("error", error);
+  }
+  function show(name) {
+    screen = name;
+    screens.forEach((el) => { el.hidden = el.dataset.settingsScreen !== name; });
+    $("settings-back-btn").hidden = name === "general";
+    $("settings-modal-footer").hidden = name === "general";
+    const key = name === "ui" ? "settings.ui.title"
+      : name === "ollama" ? "settings.ollama.title" : "settings.general.title";
+    $("settings-modal-title").textContent = t(key);
+    status("");
+  }
+  function sliders() {
+    $("temperature-value").textContent = Number($("settings-temperature").value).toFixed(1);
+    $("num-ctx-value").textContent = ctxLabels[Number($("settings-num-ctx").value)];
+  }
+  function seedMode() {
+    const fixed = $("settings-seed-mode").value === "fixed";
+    $("settings-seed").hidden = !fixed;
+    $("settings-seed").required = fixed;
+    if (!fixed) $("settings-seed").value = "";
+  }
+  function populate(data) {
+    const options = data.ollama.options;
+    $("settings-language").value = data.ui.language;
+    $("settings-system-prompt").value = data.ollama.system_prompt;
+    $("settings-temperature").value = String(options.temperature);
+    $("settings-num-ctx").value = String(Math.max(0, ctxValues.indexOf(options.num_ctx)));
+    $("settings-seed-mode").value = options.seed === undefined ? "random" : "fixed";
+    $("settings-seed").value = options.seed === undefined ? "" : String(options.seed);
+    advanced.forEach((input) => {
+      input.value = options[input.dataset.option] === undefined
+        ? "" : String(options[input.dataset.option]);
+    });
+    $("settings-stop").value = Array.isArray(options.stop) ? options.stop.join("\n") : "";
+    sliders();
+    seedMode();
+  }
+  function number(input, integer) {
+    const raw = input.value.trim();
+    if (!raw) return null;
+    const valid = integer ? /^-?\d+$/.test(raw) : Number.isFinite(Number(raw));
+    input.setCustomValidity(valid ? "" : t(integer
+      ? "settings.messages.invalid_integer" : "settings.messages.invalid_number"));
+    if (!input.reportValidity()) throw new Error(input.validationMessage);
+    return integer ? Number.parseInt(raw, 10) : Number(raw);
+  }
+  function collect() {
+    const options = {
+      temperature: Number($("settings-temperature").value),
+      num_ctx: ctxValues[Number($("settings-num-ctx").value)],
+    };
+    if ($("settings-seed-mode").value === "fixed") {
+      const value = number($("settings-seed"), true);
+      if (value === null) {
+        $("settings-seed").setCustomValidity(t("settings.messages.invalid_integer"));
+        $("settings-seed").reportValidity();
+        throw new Error("seed");
+      }
+      options.seed = value;
+    }
+    advanced.forEach((input) => {
+      input.setCustomValidity("");
+      const value = number(input, input.dataset.type === "int");
+      if (value !== null) options[input.dataset.option] = value;
+    });
+    const stop = $("settings-stop").value.split(/\r?\n/).filter((line) => line.length);
+    if (stop.length) options.stop = stop;
+    return {
+      ui: { language: $("settings-language").value },
+      ollama: { system_prompt: $("settings-system-prompt").value, options },
+    };
+  }
+  async function open() {
+    modal.classList.add("open");
+    modal.setAttribute("aria-hidden", "false");
+    show("general");
+    try {
+      const response = await request("/api/settings");
+      if (!response.ok) throw new Error(response.statusText);
+      populate(await response.json());
+    } catch (error) {
+      console.error(error);
+      status(t("settings.messages.load_failed"), true);
+    }
+  }
+  function close() {
+    modal.classList.remove("open");
+    modal.setAttribute("aria-hidden", "true");
+  }
+  async function save() {
+    let payload;
+    try { payload = collect(); } catch { return; }
+    $("settings-save-btn").disabled = true;
+    try {
+      const response = await request("/api/settings", {
+        method: "PUT", headers: { "Content-Type": "application/json" },
+        body: JSON.stringify(payload),
+      });
+      const body = await response.json().catch(() => ({}));
+      if (!response.ok) throw new Error(body.error || response.statusText);
+      if (body.ui.language !== document.documentElement.lang) {
+        location.reload();
+        return;
+      }
+      status(t("settings.messages.saved"));
+    } catch (error) {
+      status(t("settings.messages.save_failed").replace("{error}", error.message), true);
+    } finally { $("settings-save-btn").disabled = false; }
+  }
+
+  $("general-settings-btn").addEventListener("click", open);
+  $("settings-modal-close").addEventListener("click", close);
+  $("settings-back-btn").addEventListener("click", () => show("general"));
+  $("open-ui-settings").addEventListener("click", () => show("ui"));
+  $("open-ollama-settings").addEventListener("click", () => show("ollama"));
+  $("settings-save-btn").addEventListener("click", save);
+  $("settings-temperature").addEventListener("input", sliders);
+  $("settings-num-ctx").addEventListener("input", sliders);
+  $("settings-seed-mode").addEventListener("change", seedMode);
+  modal.addEventListener("click", (event) => { if (event.target === modal) close(); });
+  document.addEventListener("keydown", (event) => {
+    if (event.key === "Escape" && modal.classList.contains("open")) close();
+  });
+})();
diff --git a/src/ollama_web/static/settings.css b/src/ollama_web/static/settings.css
new file mode 100644
index 0000000..c2c778e
--- /dev/null
+++ b/src/ollama_web/static/settings.css
@@ -0,0 +1,52 @@
+.sidebar-footer { display: flex; flex-direction: column; gap: 8px; }
+.settings-modal-content { width: min(760px, 100%); }
+.settings-heading { display: flex; align-items: center; gap: 8px; }
+.settings-back-btn {
+  background: transparent; color: var(--text); border: 1px solid var(--border);
+  border-radius: 6px; padding: 3px 9px; cursor: pointer;
+}
+.settings-menu {
+  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px;
+}
+.settings-menu-card {
+  display: flex; flex-direction: column; align-items: flex-start; gap: 6px;
+  min-height: 100px; padding: 16px; text-align: left; color: var(--text);
+  background: var(--bg); border: 1px solid var(--border); border-radius: 8px;
+  cursor: pointer;
+}
+.settings-menu-card:hover { border-color: var(--accent); }
+.settings-menu-card span, .field-help { color: var(--muted); font-size: 13px; }
+.settings-field {
+  display: flex; flex-direction: column; gap: 6px; margin-bottom: 16px;
+}
+.settings-field > span { color: var(--muted); font-size: 13px; }
+.settings-field input:not([type="range"]),
+.settings-field textarea, .settings-field select,
+.seed-controls input, .seed-controls select {
+  width: 100%; padding: 8px; color: var(--text); background: var(--panel);
+  border: 1px solid var(--border); border-radius: 6px; font: inherit;
+}
+.settings-field textarea { resize: vertical; }
+.settings-field input[type="range"] { width: 100%; accent-color: var(--accent); }
+.range-labels {
+  display: flex; justify-content: space-between; color: var(--muted); font-size: 11px;
+}
+.seed-controls {
+  display: grid; grid-template-columns: minmax(180px, 1fr) minmax(120px, 1fr); gap: 8px;
+}
+.advanced-settings {
+  margin-top: 8px; padding: 12px; background: var(--bg);
+  border: 1px solid var(--border); border-radius: 8px;
+}
+.advanced-settings summary { cursor: pointer; font-weight: 600; }
+.option-grid {
+  display: grid; grid-template-columns: repeat(2, minmax(0, 1fr));
+  gap: 0 12px; margin-top: 14px;
+}
+.settings-status { min-height: 20px; color: var(--muted); font-size: 13px; }
+.settings-status.error { color: var(--danger); }
+@media (max-width: 600px) {
+  .settings-menu, .option-grid, .seed-controls { grid-template-columns: 1fr; }
+  .settings-modal-content { max-height: 95vh; }
+  .range-labels { font-size: 9px; }
+}
diff --git a/src/ollama_web/templates/index.html b/src/ollama_web/templates/index.html
index df877fa..f30b32e 100644
--- a/src/ollama_web/templates/index.html
+++ b/src/ollama_web/templates/index.html
@@ -5,6 +5,7 @@
   <meta name="viewport" content="width=device-width, initial-scale=1.0" />
   <title>ollama-web</title>
   <link rel="stylesheet" href="{{ url_for('static', path='style.css') }}" />
+  <link rel="stylesheet" href="{{ url_for('static', path='settings.css') }}" />
   <link rel="stylesheet" href="{{ url_for('static', path='vendor/github-dark.min.css') }}" />
   <link rel="stylesheet" href="{{ url_for('static', path='vendor/katex.min.css') }}" />
   <script src="{{ url_for('static', path='vendor/marked.min.js') }}"></script>
@@ -22,6 +23,7 @@
     </div>
     <ul id="session-list"></ul>
     <div class="sidebar-footer">
+      <button id="general-settings-btn" type="button">{{ t('chat.general_settings') }}</button>
       <button id="mcp-settings-btn" type="button">{{ t('chat.mcp_settings') }}</button>
     </div>
   </aside>
@@ -67,6 +69,111 @@
     </form>
   </div>
 
+  <div id="settings-modal" class="modal" aria-hidden="true">
+    <div class="modal-content settings-modal-content" role="dialog" aria-modal="true"
+         aria-labelledby="settings-modal-title">
+      <div class="modal-header">
+        <div class="settings-heading">
+          <button id="settings-back-btn" type="button" class="settings-back-btn"
+                  aria-label="{{ t('settings.back') }}">&larr;</button>
+          <h2 id="settings-modal-title">{{ t('settings.general.title') }}</h2>
+        </div>
+        <button id="settings-modal-close" type="button" class="close-btn"
+                aria-label="{{ t('common.close') }}">&times;</button>
+      </div>
+      <div class="modal-body">
+        <section class="settings-screen" data-settings-screen="general">
+          <p class="modal-help">{{ t('settings.general.description') }}</p>
+          <div class="settings-menu">
+            <button id="open-ui-settings" type="button" class="settings-menu-card">
+              <strong>{{ t('settings.ui.title') }}</strong>
+              <span>{{ t('settings.ui.description') }}</span>
+            </button>
+            <button id="open-ollama-settings" type="button" class="settings-menu-card">
+              <strong>{{ t('settings.ollama.title') }}</strong>
+              <span>{{ t('settings.ollama.description') }}</span>
+            </button>
+          </div>
+        </section>
+
+        <section class="settings-screen" data-settings-screen="ui" hidden>
+          <label class="settings-field" for="settings-language">
+            <span>{{ t('settings.ui.language') }}</span>
+            <select id="settings-language">
+              <option value="ja">日本語</option>
+              <option value="en">English</option>
+            </select>
+          </label>
+          <p class="field-help">{{ t('settings.ui.reload_notice') }}</p>
+        </section>
+
+        <section class="settings-screen" data-settings-screen="ollama" hidden>
+          <label class="settings-field" for="settings-system-prompt">
+            <span>{{ t('settings.ollama.system_prompt') }}</span>
+            <textarea id="settings-system-prompt" rows="7"
+                      placeholder="{{ t('settings.ollama.system_prompt_placeholder') }}"></textarea>
+          </label>
+
+          <label class="settings-field" for="settings-temperature">
+            <span>{{ t('settings.ollama.temperature') }}: <output id="temperature-value">0.8</output></span>
+            <input id="settings-temperature" type="range" min="0" max="2" step="0.1" value="0.8" />
+          </label>
+
+          <label class="settings-field" for="settings-num-ctx">
+            <span>{{ t('settings.ollama.num_ctx') }}: <output id="num-ctx-value">8k</output></span>
+            <input id="settings-num-ctx" type="range" min="0" max="6" step="1" value="1" />
+            <div class="range-labels" aria-hidden="true">
+              <span>4k</span><span>8k</span><span>16k</span><span>32k</span>
+              <span>64k</span><span>128k</span><span>256k</span>
+            </div>
+          </label>
+
+          <div class="settings-field">
+            <span>{{ t('settings.ollama.seed') }}</span>
+            <div class="seed-controls">
+              <select id="settings-seed-mode" aria-label="{{ t('settings.ollama.seed_mode') }}">
+                <option value="random">{{ t('settings.ollama.seed_random') }}</option>
+                <option value="fixed">{{ t('settings.ollama.seed_fixed') }}</option>
+              </select>
+              <input id="settings-seed" type="number" step="1"
+                     aria-label="{{ t('settings.ollama.seed_value') }}" hidden />
+            </div>
+          </div>
+
+          <details class="advanced-settings">
+            <summary>{{ t('settings.ollama.advanced') }}</summary>
+            <p class="field-help">{{ t('settings.ollama.blank_omitted') }}</p>
+            <div class="option-grid">
+              <label class="settings-field"><span>num_keep</span><input data-option="num_keep" data-type="int" type="number" step="1" /></label>
+              <label class="settings-field"><span>num_predict</span><input data-option="num_predict" data-type="int" type="number" step="1" /></label>
+              <label class="settings-field"><span>top_k</span><input data-option="top_k" data-type="int" type="number" step="1" /></label>
+              <label class="settings-field"><span>top_p</span><input data-option="top_p" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>min_p</span><input data-option="min_p" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>typical_p</span><input data-option="typical_p" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>tfs_z</span><input data-option="tfs_z" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>repeat_last_n</span><input data-option="repeat_last_n" data-type="int" type="number" step="1" /></label>
+              <label class="settings-field"><span>repeat_penalty</span><input data-option="repeat_penalty" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>presence_penalty</span><input data-option="presence_penalty" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>frequency_penalty</span><input data-option="frequency_penalty" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>mirostat</span><input data-option="mirostat" data-type="int" type="number" step="1" /></label>
+              <label class="settings-field"><span>mirostat_tau</span><input data-option="mirostat_tau" data-type="float" type="number" step="any" /></label>
+              <label class="settings-field"><span>mirostat_eta</span><input data-option="mirostat_eta" data-type="float" type="number" step="any" /></label>
+            </div>
+            <label class="settings-field" for="settings-stop">
+              <span>stop</span>
+              <textarea id="settings-stop" rows="4"
+                        placeholder="{{ t('settings.ollama.stop_placeholder') }}"></textarea>
+            </label>
+          </details>
+        </section>
+        <div id="settings-status" class="settings-status" role="status" aria-live="polite"></div>
+      </div>
+      <div id="settings-modal-footer" class="modal-footer" hidden>
+        <button id="settings-save-btn" type="button">{{ t('common.save') }}</button>
+      </div>
+    </div>
+  </div>
+
   <div id="mcp-modal" class="modal">
     <div class="modal-content">
       <div class="modal-header">
@@ -85,6 +192,7 @@
 
   <script src="{{ url_for('static', path='tools.js') }}"></script>
   <script src="{{ url_for('static', path='mcp.js') }}"></script>
+  <script src="{{ url_for('static', path='settings-actions.js') }}"></script>
   <script src="{{ url_for('static', path='app.js') }}"></script>
 </body>
 </html>
diff --git a/tests/test_settings.py b/tests/test_settings.py
new file mode 100644
index 0000000..6da1272
--- /dev/null
+++ b/tests/test_settings.py
@@ -0,0 +1,173 @@
+"""Tests for persisted general settings and Ollama integration."""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+from typing import Any
+
+import pytest
+from ollama import Message
+from starlette.testclient import TestClient
+
+from ollama_web import llm
+from ollama_web.app import create_app
+from ollama_web.config import settings
+from ollama_web.prompts import get_prompt
+from ollama_web.routes.chat import _compose_system_prompt
+from ollama_web.settings_store import (
+    SettingsValidationError,
+    load_app_settings,
+    save_app_settings,
+    validate_app_settings,
+)
+from ollama_web.tools.registry import ToolRegistry
+
+
+def test_missing_settings_uses_slider_defaults_and_environment_language(tmp_path: Path) -> None:
+    data = load_app_settings(tmp_path, "en")
+    assert data == {
+        "ui": {"language": "en"},
+        "ollama": {
+            "system_prompt": "",
+            "options": {"temperature": 0.8, "num_ctx": 8192},
+        },
+    }
+
+
+def test_settings_round_trip_preserves_valid_options(tmp_path: Path) -> None:
+    value = {
+        "ui": {"language": "ja"},
+        "ollama": {
+            "system_prompt": "Be concise.",
+            "options": {
+                "temperature": 0.4,
+                "num_ctx": 16384,
+                "seed": 42,
+                "num_predict": 512,
+                "top_p": 0.9,
+                "stop": ["END", "<|eot_id|>"],
+            },
+        },
+    }
+    assert save_app_settings(tmp_path, value) == value
+    assert load_app_settings(tmp_path, "en") == value
+    on_disk = json.loads((tmp_path / "settings.json").read_text(encoding="utf-8"))
+    assert on_disk == value
+
+
+def test_malformed_settings_file_falls_back_safely(tmp_path: Path) -> None:
+    (tmp_path / "settings.json").write_text("{not-json", encoding="utf-8")
+    assert load_app_settings(tmp_path, "ja")["ollama"]["options"] == {
+        "temperature": 0.8,
+        "num_ctx": 8192,
+    }
+
+
+@pytest.mark.parametrize(
+    "mutate",
+    [
+        lambda data: data.update({"unknown": True}),
+        lambda data: data["ollama"]["options"].update({"num_ctx": 12345}),
+        lambda data: data["ollama"]["options"].update({"temperature": 2.1}),
+        lambda data: data["ollama"]["options"].update({"seed": 1.5}),
+        lambda data: data["ollama"]["options"].update({"top_p": "0.9"}),
+        lambda data: data["ollama"]["options"].update({"stop": [""]}),
+    ],
+)
+def test_invalid_settings_are_rejected(mutate: Any) -> None:
+    data = {
+        "ui": {"language": "ja"},
+        "ollama": {
+            "system_prompt": "",
+            "options": {"temperature": 0.8, "num_ctx": 8192},
+        },
+    }
+    mutate(data)
+    with pytest.raises(SettingsValidationError):
+        validate_app_settings(data)
+
+
+def test_settings_api_and_page_elements(tmp_path: Path) -> None:
+    original_data_dir = settings.data_dir
+    settings.data_dir = str(tmp_path)
+    try:
+        with TestClient(create_app()) as client:
+            login = client.post("/api/auth/login", json={"pin": settings.pin})
+            csrf = login.headers["x-csrf-token"]
+            response = client.get("/api/settings")
+            assert response.status_code == 200
+            payload = response.json()
+            payload["ui"]["language"] = "en"
+            payload["ollama"]["options"]["stop"] = ["END"]
+            saved = client.put(
+                "/api/settings",
+                json=payload,
+                headers={"X-CSRF-Token": csrf},
+            )
+            assert saved.status_code == 200
+            assert client.get("/api/settings").json() == payload
+
+            bad = dict(payload)
+            bad["extra"] = True
+            rejected = client.put(
+                "/api/settings",
+                json=bad,
+                headers={"X-CSRF-Token": csrf},
+            )
+            assert rejected.status_code == 400
+
+            html = client.get("/").text
+            assert 'id="general-settings-btn"' in html
+            assert 'data-settings-screen="general"' in html
+            assert 'data-settings-screen="ui"' in html
+            assert 'data-settings-screen="ollama"' in html
+            assert html.index('id="general-settings-btn"') < html.index('id="mcp-settings-btn"')
+    finally:
+        settings.data_dir = original_data_dir
+
+
+def test_system_prompt_is_localized_and_appended() -> None:
+    custom = "Always answer briefly."
+    assert _compose_system_prompt("en", "") == get_prompt("tool_system", lang="en")
+    assert _compose_system_prompt("en", custom) == (
+        f"{get_prompt('tool_system', lang='en')}\n\n{custom}"
+    )
+
+
+def test_options_are_forwarded_to_tool_and_final_rounds(monkeypatch: pytest.MonkeyPatch) -> None:
+    class FakeClient:
+        def __init__(self) -> None:
+            self.calls: list[dict[str, Any]] = []
+
+        def chat(self, **kwargs: Any) -> dict[str, Any]:
+            self.calls.append(kwargs)
+            if len(self.calls) == 1:
+                return {
+                    "message": {
+                        "role": "assistant",
+                        "content": "",
+                        "tool_calls": [
+                            {"function": {"name": "missing_tool", "arguments": {}}}
+                        ],
+                    }
+                }
+            return {"message": {"role": "assistant", "content": "done"}}
+
+    client = FakeClient()
+    monkeypatch.setattr(llm, "get_client", lambda _host=None: client)
+    monkeypatch.setattr(llm, "MAX_TOOL_ROUNDS", 1)
+    options = {"temperature": 0.8, "num_ctx": 8192, "top_p": 0.9}
+    events = list(
+        llm.chat_with_tools(
+            [Message(role="user", content="hello")],
+            "test-model",
+            capabilities={"tools"},
+            registry=ToolRegistry(),
+            options=options,
+            language="en",
+        )
+    )
+    assert events[-1] == {"type": "done"}
+    assert len(client.calls) == 2
+    assert all(call["options"] == options for call in client.calls)