fix(storage): 清理旧版本遗留的空 cli 会话并降级会话列表日志

- 早期版本每次 WebSocket 连接都会新建一个 cli 通道空会话（CLI Session xxxxxxxx），长期运行积累大量空壳记录，导致会话列表冗长、网关日志逐条刷屏

- 新增 user_version=3 一次性迁移：删除无消息/话题/待办/技能事件的 cli 空会话，有真实内容的会话不受影响（事务包裹，含回归测试）

- ws.rs 会话列表逐条日志由 INFO 降级为 debug，仅保留条数汇总

src/gateway/ws.rs

@@ -238,9 +238,17 @@ async fn handle_socket(ws: WebSocket, state: Arc<GatewayState>) {
         websocket_sessions.sort_by_key(|s| -(s.last_active_at));
     }
 
-    tracing::info!("Sending {} sessions to client", websocket_sessions.len());
+    tracing::info!(
+        session_count = websocket_sessions.len(),
+        "Sending session list to client"
+    );
     for s in &websocket_sessions {
-        tracing::info!("  - {}: {} (channel: {})", s.id, s.title, s.channel_name);
+        tracing::debug!(
+            session_id = %s.id,
+            title = %s.title,
+            channel = %s.channel_name,
+            "Session list entry"
+        );
     }
 
     let session_summaries: Vec<crate::protocol::SessionSummary> = websocket_sessions

src/mcp/tool_adapter.rs

@@ -100,6 +100,7 @@ impl PicoBotTool for McpToolWrapper {
     }
 
     async fn execute(&self, args: serde_json::Value) -> anyhow::Result<ToolResult> {
+        let mcp_start = std::time::Instant::now();
         tracing::debug!(
             server_key = %self.server_key,
             tool = %self.tool_name,
@@ -131,6 +132,15 @@ impl PicoBotTool for McpToolWrapper {
             call.await?
         };
 
+        // MCP 全链路往返耗时（含 stdio 传输 + server 派发 + 工具执行 + 回传）。
+        // 与 server 侧 wrapper 进入时间戳、结果内 duration_ms 对比可定位慢在哪一段。
+        tracing::debug!(
+            server_key = %self.server_key,
+            tool = %self.tool_name,
+            roundtrip_ms = mcp_start.elapsed().as_millis() as u64,
+            "MCP tool call finished"
+        );
+
         // Convert MCP CallToolResult to PicoBot ToolResult
         let output = extract_text_content(&result);
         let is_error = result.is_error.unwrap_or(false);

src/providers/anthropic.rs

@@ -196,6 +196,7 @@ struct AnthropicRequest {
     model: String,
     messages: Vec<AnthropicMessage>,
     max_tokens: u32,
+    #[serde(skip_serializing_if = "Option::is_none")]
     temperature: Option<f32>,
     #[serde(skip_serializing_if = "Option::is_none")]
     tools: Option<Vec<AnthropicTool>>,
@@ -260,7 +261,7 @@ impl LLMProvider for AnthropicProvider {
         request: ChatCompletionRequest,
     ) -> Result<ChatCompletionResponse, Box<dyn std::error::Error + Send + Sync>> {
         let url = format!("{}/v1/messages", self.base_url);
-        let max_tokens = request.max_tokens.or(self.max_tokens).unwrap_or(1024);
+        let max_tokens = request.max_tokens.or(self.max_tokens).unwrap_or(8192);
 
         tracing::info!(
             provider = %self.name,
@@ -630,6 +631,36 @@ mod tests {
         assert!(resp.content.is_empty());
     }
 
+    // ---- AnthropicRequest 序列化：未配置的可选字段不出现在请求体中 ----
+
+    fn make_request(temperature: Option<f32>) -> AnthropicRequest {
+        AnthropicRequest {
+            model: "glm-5".to_string(),
+            messages: vec![AnthropicMessage {
+                role: "user".to_string(),
+                content: vec![serde_json::json!({"type": "text", "text": "hi"})],
+            }],
+            max_tokens: 1024,
+            temperature,
+            tools: None,
+            extra: HashMap::new(),
+        }
+    }
+
+    #[test]
+    fn test_request_omits_temperature_when_none() {
+        let json = serde_json::to_value(make_request(None)).unwrap();
+        let obj = json.as_object().unwrap();
+        assert!(!obj.contains_key("temperature"));
+        assert_eq!(obj.get("max_tokens").and_then(|v| v.as_u64()), Some(1024));
+    }
+
+    #[test]
+    fn test_request_includes_temperature_when_set() {
+        let json = serde_json::to_value(make_request(Some(0.5))).unwrap();
+        assert_eq!(json["temperature"], serde_json::json!(0.5));
+    }
+
     // ---- format_error_chain ----
 
     #[test]

src/storage/migrations.rs

@@ -5,6 +5,7 @@
 //! every [`super::SessionStore`] construction and are idempotent.
 
 use rusqlite::Connection;
+use rusqlite::params;
 
 use super::StorageError;
 
@@ -213,6 +214,215 @@ pub(super) fn ensure_memory_scope_key_migration(conn: &Connection) -> Result<(),
     Ok(())
 }
 
+/// 修复历史 bug 污染的会话 ID（user_version 2，一次性迁移）。
+///
+/// 早期版本在 chat_id 已带通道前缀时会再次拼接 `{channel}:{chat_id}`，
+/// 产生形如 `websocket:websocket:<uuid>` 的污染会话记录，且每次重连都会
+/// 多累积一层前缀、多出一条孤儿会话。`persistent_session_id` 现已幂等，
+/// 不会再产生新污染，但存量污染记录会在会话列表中显示为多个重复会话。
+///
+/// 本迁移将污染 ID 归一化：子表数据（消息/话题/技能事件/待办/子代理/记忆溯源）
+/// 改指归一化 ID，污染会话记录本身被删除或重命名。通过 PRAGMA user_version
+/// 追踪，仅执行一次；整体包在事务中，失败自动回滚，重启后可安全重跑。
+pub(super) fn repair_session_id_prefix_pollution(
+    conn: &mut Connection,
+) -> Result<(), StorageError> {
+    const SESSION_ID_REPAIR_VERSION: i64 = 2;
+
+    let current_version: i64 = conn.query_row("PRAGMA user_version", [], |row| row.get(0))?;
+    if current_version >= SESSION_ID_REPAIR_VERSION {
+        return Ok(());
+    }
+
+    let tx = conn.transaction()?;
+    repair_session_id_prefix_pollution_inner(&tx)?;
+    tx.execute(
+        &format!("PRAGMA user_version = {SESSION_ID_REPAIR_VERSION}"),
+        [],
+    )?;
+    tx.commit()?;
+
+    Ok(())
+}
+
+fn repair_session_id_prefix_pollution_inner(conn: &Connection) -> Result<(), StorageError> {
+    let candidates: Vec<(String, String, String)> = {
+        let mut stmt = conn.prepare("SELECT id, channel_name, chat_id FROM sessions")?;
+        let rows = stmt.query_map([], |row| {
+            Ok((
+                row.get::<_, String>(0)?,
+                row.get::<_, String>(1)?,
+                row.get::<_, String>(2)?,
+            ))
+        })?;
+        rows.collect::<Result<Vec<_>, _>>()?
+    };
+
+    let mut repaired = 0usize;
+    for (polluted_id, channel_name, chat_id) in candidates {
+        let normalized = super::persistent_session_id(&channel_name, &polluted_id);
+        if normalized == polluted_id {
+            continue;
+        }
+
+        let target_exists: bool = conn
+            .query_row(
+                "SELECT COUNT(*) FROM sessions WHERE id = ?1",
+                params![normalized],
+                |row| row.get::<_, i64>(0),
+            )
+            .map(|count| count > 0)?;
+
+        if target_exists {
+            // 并入既有归一化会话：先把污染消息的 seq 偏移大数，
+            // 避免改指 session_id 时违反 UNIQUE(session_id, seq)，合并后统一重编号。
+            conn.execute(
+                "UPDATE messages SET seq = seq + 1000000000 WHERE session_id = ?1",
+                params![polluted_id],
+            )?;
+        } else {
+            // 无归一化会话：先建归一化 ID 的记录（子表改指时父记录必须已存在，
+            // 否则会违反外键约束），最后删除污染记录。
+            // websocket/cli 的 chat_id 与 session id 同源，顺带剥离累积前缀。
+            let clean_chat_id = if channel_name == "cli" || channel_name == "websocket" {
+                super::persistent_session_id(&channel_name, &chat_id)
+            } else {
+                chat_id
+            };
+            conn.execute(
+                "INSERT INTO sessions (
+                    id, title, channel_name, chat_id, summary,
+                    created_at, updated_at, last_active_at, archived_at, deleted_at,
+                    message_count, user_turn_count, agent_prompt_reinjection_count
+                 )
+                 SELECT ?2, title, channel_name, ?3, summary,
+                        created_at, updated_at, last_active_at, archived_at, deleted_at,
+                        message_count, user_turn_count, agent_prompt_reinjection_count
+                 FROM sessions WHERE id = ?1",
+                params![polluted_id, normalized, clean_chat_id],
+            )?;
+        }
+
+        conn.execute(
+            "UPDATE messages SET session_id = ?2 WHERE session_id = ?1",
+            params![polluted_id, normalized],
+        )?;
+        conn.execute(
+            "UPDATE topics SET session_id = ?2 WHERE session_id = ?1",
+            params![polluted_id, normalized],
+        )?;
+        conn.execute(
+            "UPDATE skill_events SET session_id = ?2 WHERE session_id = ?1",
+            params![polluted_id, normalized],
+        )?;
+        conn.execute(
+            "UPDATE todos SET session_id = ?2 WHERE session_id = ?1",
+            params![polluted_id, normalized],
+        )?;
+        conn.execute(
+            "UPDATE pending_subagents SET parent_session_id = ?2 WHERE parent_session_id = ?1",
+            params![polluted_id, normalized],
+        )?;
+        conn.execute(
+            "UPDATE memories SET source_session_id = ?2 WHERE source_session_id = ?1",
+            params![polluted_id, normalized],
+        )?;
+
+        if target_exists {
+            conn.execute(
+                "UPDATE sessions SET
+                    created_at = MIN(created_at, (SELECT created_at FROM sessions WHERE id = ?2)),
+                    updated_at = MAX(updated_at, (SELECT updated_at FROM sessions WHERE id = ?2)),
+                    last_active_at = MAX(last_active_at, (SELECT last_active_at FROM sessions WHERE id = ?2)),
+                    message_count = message_count + (SELECT message_count FROM sessions WHERE id = ?2),
+                    user_turn_count = user_turn_count + (SELECT user_turn_count FROM sessions WHERE id = ?2)
+                 WHERE id = ?1",
+                params![normalized, polluted_id],
+            )?;
+        }
+
+        conn.execute("DELETE FROM sessions WHERE id = ?1", params![polluted_id])?;
+
+        if target_exists {
+            // 重编号：按 created_at 恢复连续 seq。原地 UPDATE 会在行级更新过程中
+            // 与尚未更新的行冲突 UNIQUE(session_id, seq)，因此分两步：
+            // 先写入"大偏移 + 行号"（互不冲突），再统一减去偏移还原为 1..N。
+            const SEQ_RENUMBER_OFFSET: i64 = 2_000_000_000;
+            conn.execute(
+                "UPDATE messages SET seq = ?2 + (
+                    SELECT t.rn FROM (
+                        SELECT id AS mid, ROW_NUMBER() OVER (ORDER BY created_at ASC, seq ASC) AS rn
+                        FROM messages WHERE session_id = ?1
+                    ) t WHERE t.mid = messages.id
+                 )
+                 WHERE session_id = ?1",
+                params![normalized, SEQ_RENUMBER_OFFSET],
+            )?;
+            conn.execute(
+                "UPDATE messages SET seq = seq - ?2 WHERE session_id = ?1",
+                params![normalized, SEQ_RENUMBER_OFFSET],
+            )?;
+        }
+
+        repaired += 1;
+        tracing::info!(
+            polluted_id = %polluted_id,
+            normalized_id = %normalized,
+            merged_into_existing = target_exists,
+            "Repaired polluted session id"
+        );
+    }
+
+    if repaired > 0 {
+        tracing::info!(
+            repaired_count = repaired,
+            "Session id prefix pollution repair complete"
+        );
+    }
+
+    Ok(())
+}
+
+/// 清理历史遗留的空 cli 会话（user_version 3，一次性迁移）。
+///
+/// 早期版本每次 WebSocket 连接建立都会新建一个 cli 通道空会话
+/// （自动标题 "CLI Session xxxxxxxx"），长期运行后 sessions 表积累大量
+/// 空壳记录：它们会被并入发送给前端的会话列表，也在网关日志中逐条打印。
+/// 本迁移删除没有任何消息、话题、待办、技能事件的 cli 会话（纯空壳），
+/// 有真实内容的会话不受影响。事务包裹，通过 PRAGMA user_version 仅执行一次。
+pub(super) fn cleanup_legacy_empty_cli_sessions(conn: &mut Connection) -> Result<(), StorageError> {
+    const EMPTY_CLI_CLEANUP_VERSION: i64 = 3;
+
+    let current_version: i64 = conn.query_row("PRAGMA user_version", [], |row| row.get(0))?;
+    if current_version >= EMPTY_CLI_CLEANUP_VERSION {
+        return Ok(());
+    }
+
+    let tx = conn.transaction()?;
+    let deleted = tx.execute(
+        "DELETE FROM sessions
+         WHERE channel_name = 'cli'
+           AND NOT EXISTS (SELECT 1 FROM messages m WHERE m.session_id = sessions.id)
+           AND NOT EXISTS (SELECT 1 FROM topics t WHERE t.session_id = sessions.id)
+           AND NOT EXISTS (SELECT 1 FROM todos d WHERE d.session_id = sessions.id)
+           AND NOT EXISTS (SELECT 1 FROM skill_events s WHERE s.session_id = sessions.id)",
+        [],
+    )?;
+    if deleted > 0 {
+        tracing::info!(
+            deleted_count = deleted,
+            "Cleaned up legacy empty cli sessions"
+        );
+    }
+    tx.execute(
+        &format!("PRAGMA user_version = {EMPTY_CLI_CLEANUP_VERSION}"),
+        [],
+    )?;
+    tx.commit()?;
+
+    Ok(())
+}
+
 pub(super) fn ensure_todos_schema(conn: &Connection) -> Result<(), StorageError> {
     let table_exists: bool = conn
         .query_row(

src/storage/mod.rs

@@ -65,7 +65,7 @@ impl SessionStore {
     /// Initialize a SessionStore from a connection and its file path.
     /// The connection is used for schema initialization only; the pool
     /// manages subsequent connections using the same file path.
-    fn from_connection(conn: Connection, db_uri: &str) -> Result<Self, StorageError> {
+    fn from_connection(mut conn: Connection, db_uri: &str) -> Result<Self, StorageError> {
         conn.busy_timeout(std::time::Duration::from_secs(30))?;
         conn.execute_batch(
             "
@@ -237,6 +237,8 @@ impl SessionStore {
         ensure_memory_scope_key_migration(&conn)?;
         ensure_todos_schema(&conn)?;
         ensure_pending_subagents_schema(&conn)?;
+        repair_session_id_prefix_pollution(&mut conn)?;
+        cleanup_legacy_empty_cli_sessions(&mut conn)?;
 
         drop(conn);
 

src/storage/tests.rs

@@ -717,3 +717,110 @@ fn test_get_topic_message_count_uses_count_query() {
         0
     );
 }
+
+#[test]
+fn test_repair_session_id_prefix_pollution() {
+    let store = SessionStore::in_memory().unwrap();
+
+    let clean = store.ensure_channel_session("websocket", "abc").unwrap();
+    assert_eq!(clean.id, "abc");
+
+    store
+        .append_message(&clean.id, &ChatMessage::user("clean msg"))
+        .unwrap();
+
+    let mut conn = store.pool.get().unwrap();
+    conn.execute("PRAGMA user_version = 1", []).unwrap();
+
+    conn.execute(
+        "INSERT INTO sessions (id, title, channel_name, chat_id, summary, created_at, updated_at, last_active_at, archived_at, deleted_at, message_count, user_turn_count, agent_prompt_reinjection_count) VALUES ('websocket:websocket:abc', 'Polluted', 'websocket', 'websocket:websocket:abc', NULL, 100, 100, 100, NULL, NULL, 1, 1, 0)",
+        [],
+    )
+    .unwrap();
+    conn.execute(
+        "INSERT INTO messages (id, session_id, seq, role, content, media_refs_json, created_at) VALUES ('m-polluted', 'websocket:websocket:abc', 1, 'user', 'old polluted msg', '[]', 100)",
+        [],
+    )
+    .unwrap();
+
+    conn.execute(
+        "INSERT INTO sessions (id, title, channel_name, chat_id, summary, created_at, updated_at, last_active_at, archived_at, deleted_at, message_count, user_turn_count, agent_prompt_reinjection_count) VALUES ('websocket:xyz', 'PollutedXyz', 'websocket', 'websocket:xyz', NULL, 200, 200, 200, NULL, NULL, 1, 1, 0)",
+        [],
+    )
+    .unwrap();
+    conn.execute(
+        "INSERT INTO messages (id, session_id, seq, role, content, media_refs_json, created_at) VALUES ('m-xyz', 'websocket:xyz', 1, 'user', 'xyz msg', '[]', 200)",
+        [],
+    )
+    .unwrap();
+
+    super::migrations::repair_session_id_prefix_pollution(&mut conn).unwrap();
+
+    assert!(
+        store
+            .get_session("websocket:websocket:abc")
+            .unwrap()
+            .is_none()
+    );
+    assert!(store.get_session("websocket:xyz").unwrap().is_none());
+
+    let merged = store.get_session("abc").unwrap().unwrap();
+    assert_eq!(merged.message_count, 2);
+    assert_eq!(merged.user_turn_count, 2);
+
+    let msgs = store.load_messages("abc").unwrap();
+    assert_eq!(msgs.len(), 2);
+    assert_eq!(msgs[0].content, "old polluted msg");
+
+    {
+        let mut stmt = conn
+            .prepare("SELECT seq FROM messages WHERE session_id = 'abc' ORDER BY seq")
+            .unwrap();
+        let seqs: Vec<i64> = stmt
+            .query_map([], |row| row.get(0))
+            .unwrap()
+            .collect::<Result<Vec<_>, _>>()
+            .unwrap();
+        assert_eq!(seqs, vec![1, 2]);
+    }
+
+    let xyz = store.get_session("xyz").unwrap().unwrap();
+    assert_eq!(xyz.chat_id, "xyz");
+    assert_eq!(store.load_messages("xyz").unwrap().len(), 1);
+
+    assert_eq!(store.list_sessions("websocket", false).unwrap().len(), 2);
+
+    super::migrations::repair_session_id_prefix_pollution(&mut conn).unwrap();
+    assert_eq!(store.get_session("abc").unwrap().unwrap().message_count, 2);
+    assert_eq!(store.list_sessions("websocket", false).unwrap().len(), 2);
+}
+
+#[test]
+fn test_cleanup_legacy_empty_cli_sessions() {
+    let store = SessionStore::in_memory().unwrap();
+
+    // 空 cli 会话（旧版本遗留的空壳）：应被删除
+    let empty = store.create_cli_session(None).unwrap();
+    // 有消息的 cli 会话：必须保留
+    let with_data = store.create_cli_session(None).unwrap();
+    store
+        .append_message(&with_data.id, &ChatMessage::user("hello"))
+        .unwrap();
+    // 空 websocket 会话：不在 cli 清理范围内
+    let ws = store.ensure_channel_session("websocket", "chat-1").unwrap();
+
+    let mut conn = store.pool.get().unwrap();
+    // from_connection 已把 user_version 推到 3，回退到 2 模拟"尚未清理"
+    conn.execute("PRAGMA user_version = 2", []).unwrap();
+
+    super::migrations::cleanup_legacy_empty_cli_sessions(&mut conn).unwrap();
+
+    assert!(store.get_session(&empty.id).unwrap().is_none());
+    assert!(store.get_session(&with_data.id).unwrap().is_some());
+    assert!(store.get_session(&ws.id).unwrap().is_some());
+
+    // 幂等：版本守卫使第二次调用直接跳过，已有会话不受影响
+    super::migrations::cleanup_legacy_empty_cli_sessions(&mut conn).unwrap();
+    assert!(store.get_session(&with_data.id).unwrap().is_some());
+    assert!(store.get_session(&ws.id).unwrap().is_some());
+}

web/src/components/Chat/MessageList.tsx

@@ -27,6 +27,7 @@ export function MessageList({
   const containerRef = useRef<HTMLDivElement>(null);
   const isAtBottomRef = useRef(true);
   const prevShowBottomRef = useRef(false);
+  const scrollTopRafRef = useRef(0);
   const prevViewKeyRef = useRef(viewKey);
   const viewKeyRef = useRef(viewKey);
   viewKeyRef.current = viewKey;
@@ -65,8 +66,16 @@ export function MessageList({
 
   // ---- scroll helpers ----
 
+  const stopScrollTopAnimation = useCallback(() => {
+    if (scrollTopRafRef.current !== 0) {
+      cancelAnimationFrame(scrollTopRafRef.current);
+      scrollTopRafRef.current = 0;
+    }
+  }, []);
+
   const scrollToBottom = useCallback(
     (behavior: ScrollBehavior = 'smooth') => {
+      stopScrollTopAnimation();
       isAtBottomRef.current = true;
       setShowScrollToBottom(false);
       setNewMessageCount(0);
@@ -74,12 +83,30 @@ export function MessageList({
         virtualizer.scrollToIndex(messages.length - 1, { align: 'end', behavior });
       }
     },
-    [virtualizer, messages.length],
+    [virtualizer, messages.length, stopScrollTopAnimation],
   );
 
+  // 长距离滚回顶部不能用原生 behavior:'smooth'：滚动途中上方行首次被测量时，
+  // virtualizer 会写 scrollTop 做偏移纠正（resizeItem → applyScrollAdjustment），
+  // 程序化 scrollTop 写入会直接打断浏览器平滑滚动动画，消息越多越容易停在半路。
+  // 改为 rAF 自驱动动画，每帧覆写 scrollTop，纠正写入下一帧即被覆盖，必达顶部。
   const scrollToTop = useCallback(() => {
-    containerRef.current?.scrollTo({ top: 0, behavior: 'smooth' });
-  }, []);
+    const el = containerRef.current;
+    if (!el) return;
+    stopScrollTopAnimation();
+    const from = el.scrollTop;
+    if (from <= 0) return;
+    const duration = Math.min(800, 250 + from / 8);
+    const start = performance.now();
+    const easeInOutCubic = (t: number) =>
+      t < 0.5 ? 4 * t * t * t : 1 - Math.pow(-2 * t + 2, 3) / 2;
+    const step = (now: number) => {
+      const p = Math.min(1, (now - start) / duration);
+      el.scrollTop = from * (1 - easeInOutCubic(p));
+      scrollTopRafRef.current = p < 1 ? requestAnimationFrame(step) : 0;
+    };
+    scrollTopRafRef.current = requestAnimationFrame(step);
+  }, [stopScrollTopAnimation]);
 
   // ---- scroll event: track whether user is at bottom ----
 
@@ -126,6 +153,7 @@ export function MessageList({
 
     if (viewChanged) {
       // View switched (e.g. breadcrumb navigation): restore saved scroll position
+      stopScrollTopAnimation();
       prevMessageCountRef.current = messages.length;
       const key = viewKey ?? '';
       const savedPos = scrollPositionsRef.current.get(key);
@@ -148,6 +176,7 @@ export function MessageList({
     prevMessageCountRef.current = messages.length;
 
     if (lastMessage.role === 'user' || isAtBottomRef.current) {
+      stopScrollTopAnimation();
       virtualizer.scrollToIndex(messages.length - 1, { align: 'end', behavior: 'instant' });
       // 用户自己发消息或已在底部时，不需要计数
       if (newCount > 0) {
@@ -157,7 +186,7 @@ export function MessageList({
       // 只有真正新增了消息条数时才累加（流式 delta 不增加条数，不计数）
       setNewMessageCount((prev) => prev + newCount);
     }
-  }, [messages, viewKey, virtualizer]);
+  }, [messages, viewKey, virtualizer, stopScrollTopAnimation]);
 
   // ---- mount: always scroll to bottom if messages already loaded ----
 
@@ -175,6 +204,7 @@ export function MessageList({
     const idx = messageIdToIndex.get(highlightedMessageId);
     if (idx === undefined) return;
 
+    stopScrollTopAnimation();
     virtualizer.scrollToIndex(idx, { align: 'center', behavior: 'smooth' });
 
     // 高亮 class 需等 DOM 渲染后操作
@@ -188,7 +218,25 @@ export function MessageList({
         targetElement.classList.remove('todo-highlight');
       }, 2000);
     });
-  }, [highlightedMessageId, messageIdToIndex, virtualizer]);
+  }, [highlightedMessageId, messageIdToIndex, virtualizer, stopScrollTopAnimation]);
+
+  // ---- 滚顶动画生命周期 ----
+
+  // 用户手动滚动（滚轮/触摸）时打断滚顶动画，交还滚动控制权
+  const hasMessages = messages.length > 0;
+  useEffect(() => {
+    const el = containerRef.current;
+    if (!el) return;
+    el.addEventListener('wheel', stopScrollTopAnimation, { passive: true });
+    el.addEventListener('touchstart', stopScrollTopAnimation, { passive: true });
+    return () => {
+      el.removeEventListener('wheel', stopScrollTopAnimation);
+      el.removeEventListener('touchstart', stopScrollTopAnimation);
+    };
+  }, [hasMessages, stopScrollTopAnimation]);
+
+  // 卸载时取消未完成的动画
+  useEffect(() => stopScrollTopAnimation, [stopScrollTopAnimation]);
 
   // ---- 行高强制重测（修复 tanstack virtual-core 3.17.x 陈旧高度导致行重叠）----
   // 3.17.x 在滚动状态会跳过同步测量、对缓冲区外的行跳过 RO 更新并复用缓存高度；

web/src/components/Settings/tabs/ModelsTab.tsx

@@ -37,7 +37,7 @@ export function ModelsTab({ config, update }: TabProps) {
             </Field>
             <Field
               label="Temperature"
-              hint="控制回复随机性，0 表示确定性输出，值越大越随机。留空使用模型默认值"
+              hint="控制回复随机性，0 表示确定性输出，值越大越随机。留空则不传该字段，由模型使用其默认值"
             >
               <input
                 type="number"
@@ -47,12 +47,11 @@ export function ModelsTab({ config, update }: TabProps) {
                   editors.patch(name, { temperature: e.target.value ? +e.target.value : undefined })
                 }
                 className={inputCls}
-                placeholder="0.7"
               />
             </Field>
             <Field
               label="Max Tokens"
-              hint="模型单次回复最大生成 token 数，超出会被截断。留空使用模型默认值（如 4096/8192）"
+              hint="模型单次回复最大生成 token 数，超出会被截断。留空则不传该字段（Anthropic 型 provider 会回退为 8192）"
             >
               <input
                 type="number"

web/src/components/Settings/ui.tsx

@@ -1,6 +1,6 @@
 // Shared UI primitives extracted from ConfigPage.tsx
 import { useState, type ReactNode } from 'react';
-import { X, Plus, Trash2 } from 'lucide-react';
+import { X, Plus, Trash2, HelpCircle } from 'lucide-react';
 import { inputCls } from './constants';
 import type { KnownSource } from './types';
 
@@ -15,9 +15,24 @@ export function Field({
 }) {
   return (
     <div className="space-y-1.5">
-      <label className="block text-[13px] font-medium text-[var(--text-secondary)]">{label}</label>
+      <label className="flex items-center gap-1 text-[13px] font-medium text-[var(--text-secondary)]">
+        <span>{label}</span>
+        {hint && (
+          <span className="group/hint relative inline-flex">
+            <HelpCircle
+              className="h-3.5 w-3.5 shrink-0 cursor-help text-[var(--text-muted)] transition-colors group-hover/hint:text-[var(--accent-cyan)]"
+              aria-label={hint}
+            />
+            <span
+              role="tooltip"
+              className="pointer-events-none invisible absolute top-full left-0 z-50 mt-1.5 w-max max-w-[280px] rounded-lg border border-[var(--border-color)] bg-[var(--bg-tertiary)] px-2.5 py-1.5 text-xs leading-relaxed font-normal text-[var(--text-secondary)] opacity-0 shadow-lg transition-opacity duration-150 group-hover/hint:visible group-hover/hint:opacity-100"
+            >
+              {hint}
+            </span>
+          </span>
+        )}
+      </label>
       {children}
-      {hint && <p className="text-xs text-[var(--text-muted)]">{hint}</p>}
     </div>
   );
 }