feat: 更新 StopExecution 命令和 CancelManager，支持按话题取消 Agent 执行

src/agent/agent_loop.rs

@@ -646,6 +646,8 @@ pub struct AgentLoop {
     observer: Option<Arc<dyn Observer>>,
     emitted_message_handler: Option<Arc<dyn EmittedMessageHandler>>,
     max_iterations: usize,
+    /// 取消信号接收端：Agent 在每次迭代开始时检查是否被取消
+    cancel_token: Option<tokio::sync::watch::Receiver<()>>,
 }
 
 #[derive(Debug, Clone)]
@@ -742,6 +744,7 @@ impl AgentLoop {
             tool_context: ToolContext::default(),
             observer: None,
             emitted_message_handler: None,
+            cancel_token: None,
             max_iterations,
         })
     }
@@ -764,6 +767,7 @@ impl AgentLoop {
             tool_context: ToolContext::default(),
             observer: None,
             emitted_message_handler: None,
+            cancel_token: None,
             max_iterations,
         })
     }
@@ -787,6 +791,7 @@ impl AgentLoop {
             tool_context: ToolContext::default(),
             observer: None,
             emitted_message_handler: None,
+            cancel_token: None,
             max_iterations,
         })
     }
@@ -814,6 +819,7 @@ impl AgentLoop {
             tool_context: ToolContext::default(),
             observer: None,
             emitted_message_handler: None,
+            cancel_token: None,
             max_iterations,
         })
     }
@@ -834,122 +840,129 @@ impl AgentLoop {
         self
     }
 
+    /// 设置取消信号接收端。
+    ///
+    /// Agent 在每次迭代开始时检查 `cancel_token.has_changed()`，
+    /// 如果已收到取消信号则提前返回。
+    pub fn with_cancel_token(mut self, token: tokio::sync::watch::Receiver<()>) -> Self {
+        self.cancel_token = Some(token);
+        self
+    }
+
     pub fn tools(&self) -> &Arc<ToolRegistry> {
         &self.tools
     }
 
-    /// Sanitize message history by removing trailing assistant messages with
-    /// tool_calls that don't have corresponding tool result messages.
+    /// Sanitize message history by removing assistant messages with tool_calls
+    /// that don't have corresponding tool result messages, at ANY position in
+    /// the history (not just trailing).
     ///
-    /// This can happen if the process was interrupted mid-execution: the
-    /// assistant message with tool_calls was persisted but the tool results
-    /// were not. Sending such incomplete sequences to the API causes errors
-    /// like "insufficient tool messages following tool_calls message".
+    /// Incomplete sequences can appear in the middle of history when:
+    /// 1. The process was interrupted mid-execution (before commit cb58d9f),
+    ///    then a new user message was appended, burying the orphan.
+    /// 2. History compaction preserves orphaned tool_calls from a pre-fix era
+    ///    or from a race condition between persistence and snapshot.
+    ///
+    /// Sending such incomplete sequences to the API causes errors like
+    /// "insufficient tool messages following tool_calls message".
     ///
     /// Returns the number of messages removed.
     fn sanitize_incomplete_tool_call_sequences(messages: &mut Vec<ChatMessage>) -> usize {
+        use std::collections::HashSet;
+
         let mut removed = 0;
 
-        // Phase 1: Remove trailing assistant messages with tool_calls that lack
-        // corresponding tool result messages. We loop because removing one may
-        // expose another incomplete sequence.
-        loop {
-            let last_assistant_idx = match messages.iter().rposition(|m| {
-                m.role == "assistant"
-                    && m.tool_calls
-                        .as_ref()
-                        .map_or(false, |calls| !calls.is_empty())
-            }) {
-                Some(idx) => idx,
-                None => break,
-            };
+        // Phase 1: Single reverse pass to find ALL assistant messages with
+        // incomplete tool_calls, regardless of position.
+        //
+        // Scanning right-to-left means we encounter tool results before their
+        // parent assistants, so we naturally know which tool_call_ids have
+        // corresponding results.
+        let mut resolved_ids: HashSet<String> = HashSet::new();
+        let mut with_parent: HashSet<String> = HashSet::new();
+        let mut remove_indices: Vec<usize> = Vec::new();
 
-            // Collect all tool_call_ids from this assistant message
-            let tool_call_ids: Vec<&str> = messages[last_assistant_idx]
-                .tool_calls
-                .as_ref()
-                .unwrap()
-                .iter()
-                .map(|tc| tc.id.as_str())
-                .collect();
+        // Phase 1: Reverse pass — collect tool result IDs first, then
+        // validate each assistant's tool_calls against already-seen results.
+        //
+        // Because we scan right-to-left, any tool result we've already seen
+        // appears AFTER the current message in forward order. This correctly
+        // identifies which assistant tool_calls have corresponding results.
+        for i in (0..messages.len()).rev() {
+            let msg = &messages[i];
 
-            // Check if ALL tool_call_ids have corresponding tool messages
-            // appearing AFTER this assistant message
-            let all_have_results = tool_call_ids.iter().all(|&tc_id| {
-                messages[last_assistant_idx + 1..]
-                    .iter()
-                    .any(|m| m.role == "tool" && m.tool_call_id.as_deref() == Some(tc_id))
-            });
-
-            if all_have_results {
-                // Complete sequence found, stop trimming
-                break;
+            if msg.role == "tool" {
+                if let Some(ref tc_id) = msg.tool_call_id {
+                    resolved_ids.insert(tc_id.clone());
+                }
             }
 
-            let tool_call_count = tool_call_ids.len();
-            let missing_count = tool_call_ids
-                .iter()
-                .filter(|&&tc_id| {
-                    !messages[last_assistant_idx + 1..]
+            if msg.role == "assistant"
+                && msg.tool_calls.as_ref().map_or(false, |calls| !calls.is_empty())
+            {
+                let tool_calls = msg.tool_calls.as_ref().unwrap();
+                let all_have_results = tool_calls
+                    .iter()
+                    .all(|tc| resolved_ids.contains(&tc.id));
+
+                if all_have_results {
+                    for tc in tool_calls.iter() {
+                        with_parent.insert(tc.id.clone());
+                    }
+                } else {
+                    let missing_count = tool_calls
                         .iter()
-                        .any(|m| m.role == "tool" && m.tool_call_id.as_deref() == Some(tc_id))
-                })
-                .count();
+                        .filter(|tc| !resolved_ids.contains(&tc.id))
+                        .count();
 
-            tracing::warn!(
-                tool_call_count,
-                missing_tool_results = missing_count,
-                message_id = %messages[last_assistant_idx].id,
-                "Removing assistant message with incomplete tool call sequence — \
-                 tool results were never persisted (likely due to process interruption)"
-            );
+                    tracing::warn!(
+                        tool_call_count = tool_calls.len(),
+                        missing_tool_results = missing_count,
+                        message_id = %msg.id,
+                        message_index = i,
+                        "Removing assistant message with incomplete tool call sequence — \
+                         tool results were never persisted (likely due to process interruption \
+                         or history compaction preserving an orphan)"
+                    );
 
-            messages.remove(last_assistant_idx);
+                    remove_indices.push(i);
+                }
+            }
+        }
+
+        // Remove in descending index order to avoid shifting
+        for &idx in &remove_indices {
+            messages.remove(idx);
             removed += 1;
         }
 
-        // Phase 2: Remove orphaned trailing tool messages that no longer have a
-        // corresponding assistant tool_calls message before them. These are left
-        // over from Phase 1 removals.
-        //
-        // We work backwards: a tool message at the end of the sequence is
-        // orphaned if none of the preceding messages is an assistant with a
-        // matching tool_call in its tool_calls.
-        while let Some(last_idx) = messages.last().map(|_| messages.len() - 1) {
-            let last = &messages[last_idx];
-            if last.role != "tool" {
-                break;
+        // Phase 2: Forward pass to remove ALL orphaned tool messages (not just
+        // trailing ones). A tool message is orphaned if its tool_call_id has no
+        // matching parent assistant remaining in the history.
+        if !with_parent.is_empty() || !resolved_ids.is_empty() {
+            let mut i = 0;
+            while i < messages.len() {
+                let msg = &messages[i];
+                if msg.role == "tool" {
+                    let is_orphaned = match &msg.tool_call_id {
+                        Some(tc_id) => !with_parent.contains(tc_id),
+                        None => true,
+                    };
+                    if is_orphaned {
+                        tracing::warn!(
+                            tool_call_id = ?msg.tool_call_id,
+                            message_id = %msg.id,
+                            message_index = i,
+                            "Removing orphaned tool result message — its parent assistant \
+                             tool_calls message was removed or never persisted"
+                        );
+                        messages.remove(i);
+                        removed += 1;
+                        continue;
+                    }
+                }
+                i += 1;
             }
-
-            let tool_id = match &last.tool_call_id {
-                Some(id) => id.as_str(),
-                None => break, // tool message without tool_call_id — shouldn't happen, but safe
-            };
-
-            // Check if any preceding assistant message has this tool_call_id in
-            // its tool_calls
-            let has_parent = messages[..last_idx].iter().any(|m| {
-                m.role == "assistant"
-                    && m.tool_calls
-                        .as_ref()
-                        .map_or(false, |calls| {
-                            calls.iter().any(|tc| tc.id == tool_id)
-                        })
-            });
-
-            if has_parent {
-                break; // This tool message has a valid parent, stop
-            }
-
-            tracing::warn!(
-                tool_call_id = %tool_id,
-                message_id = %last.id,
-                "Removing orphaned tool result message — its parent assistant \
-                 tool_calls message was removed or never persisted"
-            );
-
-            messages.remove(last_idx);
-            removed += 1;
         }
 
         removed
@@ -990,6 +1003,25 @@ impl AgentLoop {
             #[cfg(debug_assertions)]
             tracing::debug!(iteration, "Agent iteration started");
 
+            // 检查取消信号
+            if let Some(ref token) = self.cancel_token {
+                if token.has_changed().unwrap_or(false) {
+                    tracing::info!(iteration, "Agent execution cancelled by user");
+                    let cancel_message = format!(
+                        "\n\n[用户已取消执行。已迭代 {} 次，取消前共生成了 {} 条消息。]",
+                        iteration,
+                        emitted_messages.len()
+                    );
+                    let assistant_message = ChatMessage::assistant(cancel_message);
+                    emitted_messages.push(assistant_message.clone());
+                    self.emit_live_tool_call_message(assistant_message.clone()).await;
+                    return Ok(AgentProcessResult {
+                        final_response: assistant_message,
+                        emitted_messages,
+                    });
+                }
+            }
+
             // Build request
             let tool_defs = self.tools.get_definitions();
             let tools = if tool_defs.is_empty() {
@@ -2096,6 +2128,190 @@ mod tests {
         assert_eq!(messages[3].content, "the answer is 2");
         assert_eq!(messages[4].content, "second question");
     }
+
+    #[test]
+    fn test_sanitize_removes_mid_history_orphaned_tool_calls() {
+        // Bug scenario: orphaned tool_calls in the MIDDLE of history,
+        // followed by a complete sequence. The old trailing-only sanitizer
+        // would stop at the complete sequence and never remove the orphan.
+        let mut messages = vec![
+            ChatMessage::user("first question"),
+            ChatMessage::assistant_with_tool_calls(
+                "orphaned tool call",
+                vec![ToolCall {
+                    id: "call_1".to_string(),
+                    name: "calculator".to_string(),
+                    arguments: serde_json::json!({"expression": "1+1"}),
+                }],
+            ),
+            // Missing tool result for call_1 — ORPHAN in the middle
+            ChatMessage::user("second question"),
+            ChatMessage::assistant_with_tool_calls(
+                "valid tool call",
+                vec![ToolCall {
+                    id: "call_2".to_string(),
+                    name: "read".to_string(),
+                    arguments: serde_json::json!({"path": "README.md"}),
+                }],
+            ),
+            ChatMessage::tool("call_2", "read", "file contents"),
+        ];
+
+        let removed = AgentLoop::sanitize_incomplete_tool_call_sequences(&mut messages);
+        // call_1 assistant removed (1), rest preserved (4)
+        assert_eq!(removed, 1);
+        assert_eq!(messages.len(), 4);
+        assert_eq!(messages[0].role, "user");
+        assert_eq!(messages[0].content, "first question");
+        assert_eq!(messages[1].role, "user");
+        assert_eq!(messages[1].content, "second question");
+        // The complete call_2 sequence is preserved
+        assert_eq!(messages[2].role, "assistant");
+        assert_eq!(messages[3].role, "tool");
+    }
+
+    #[test]
+    fn test_sanitize_removes_multiple_mid_history_orphans() {
+        // Multiple orphaned tool_calls scattered throughout history
+        let mut messages = vec![
+            ChatMessage::user("first"),
+            ChatMessage::assistant_with_tool_calls(
+                "orphan 1",
+                vec![ToolCall {
+                    id: "orphan_1".to_string(),
+                    name: "tool_a".to_string(),
+                    arguments: serde_json::json!({}),
+                }],
+            ),
+            // Missing result for orphan_1
+            ChatMessage::user("second"),
+            ChatMessage::assistant_with_tool_calls(
+                "orphan 2",
+                vec![ToolCall {
+                    id: "orphan_2".to_string(),
+                    name: "tool_b".to_string(),
+                    arguments: serde_json::json!({}),
+                }],
+            ),
+            // Missing result for orphan_2
+            ChatMessage::user("third"),
+        ];
+
+        let removed = AgentLoop::sanitize_incomplete_tool_call_sequences(&mut messages);
+        assert_eq!(removed, 2);
+        assert_eq!(messages.len(), 3);
+        assert_eq!(messages[0].content, "first");
+        assert_eq!(messages[1].content, "second");
+        assert_eq!(messages[2].content, "third");
+    }
+
+    #[test]
+    fn test_sanitize_removes_orphaned_tool_results_for_removed_mid_assistant() {
+        // When removing a mid-history assistant with partial tool results,
+        // both the assistant AND its orphaned tool results must be removed.
+        // Assistant has 2 tool calls, only 1 has a result → assistant is
+        // incomplete → both assistant and its lone tool result removed.
+        let mut messages = vec![
+            ChatMessage::user("first question"),
+            ChatMessage::assistant_with_tool_calls(
+                "two tool calls, only one has result",
+                vec![
+                    ToolCall {
+                        id: "call_has_result".to_string(),
+                        name: "tool_a".to_string(),
+                        arguments: serde_json::json!({}),
+                    },
+                    ToolCall {
+                        id: "call_no_result".to_string(),
+                        name: "tool_b".to_string(),
+                        arguments: serde_json::json!({}),
+                    },
+                ],
+            ),
+            ChatMessage::tool("call_has_result", "tool_a", "some result"),
+            // Missing tool result for call_no_result → incomplete sequence
+            ChatMessage::user("second question"),
+            ChatMessage::assistant_with_tool_calls(
+                "valid tool call",
+                vec![ToolCall {
+                    id: "call_valid".to_string(),
+                    name: "good_tool".to_string(),
+                    arguments: serde_json::json!({}),
+                }],
+            ),
+            ChatMessage::tool("call_valid", "good_tool", "valid result"),
+        ];
+
+        let removed = AgentLoop::sanitize_incomplete_tool_call_sequences(&mut messages);
+        // call_has_result/call_no_result assistant (1) + its orphaned tool result (1) = 2 removed
+        assert_eq!(removed, 2);
+        assert_eq!(messages.len(), 4);
+        assert_eq!(messages[0].content, "first question");
+        assert_eq!(messages[1].content, "second question");
+        assert_eq!(messages[2].role, "assistant");
+        assert_eq!(messages[3].role, "tool");
+        // Verify the remaining tool belongs to call_valid
+        assert_eq!(messages[3].tool_call_id.as_deref(), Some("call_valid"));
+    }
+
+    #[test]
+    fn test_sanitize_handles_complex_interleaved_history() {
+        // Complete → Orphaned → Complete: a realistic scenario after
+        // history compaction
+        let mut messages = vec![
+            ChatMessage::user("task 1"),
+            ChatMessage::assistant_with_tool_calls(
+                "doing task 1",
+                vec![ToolCall {
+                    id: "t1_call".to_string(),
+                    name: "read".to_string(),
+                    arguments: serde_json::json!({"path": "a.txt"}),
+                }],
+            ),
+            ChatMessage::tool("t1_call", "read", "content A"),
+            ChatMessage::assistant("task 1 is done"),
+            // End of task 1 — complete sequence
+
+            ChatMessage::user("task 2"),
+            ChatMessage::assistant_with_tool_calls(
+                "doing task 2 — this got interrupted",
+                vec![
+                    ToolCall {
+                        id: "t2_call_1".to_string(),
+                        name: "write".to_string(),
+                        arguments: serde_json::json!({"path": "b.txt"}),
+                    },
+                    ToolCall {
+                        id: "t2_call_2".to_string(),
+                        name: "calculator".to_string(),
+                        arguments: serde_json::json!({"expression": "2+2"}),
+                    },
+                ],
+            ),
+            // Missing BOTH tool results — process was killed here
+            // End of task 2 — orphaned sequence in the middle
+
+            ChatMessage::user("task 3"),
+            ChatMessage::assistant_with_tool_calls(
+                "doing task 3",
+                vec![ToolCall {
+                    id: "t3_call".to_string(),
+                    name: "search".to_string(),
+                    arguments: serde_json::json!({"query": "hello"}),
+                }],
+            ),
+            ChatMessage::tool("t3_call", "search", "found results"),
+            ChatMessage::assistant("task 3 is done"),
+        ];
+
+        let removed = AgentLoop::sanitize_incomplete_tool_call_sequences(&mut messages);
+        // Removed: assistant with t2_call_1/t2_call_2 (1 message)
+        assert_eq!(removed, 1);
+        // Original 10 messages - 1 = 9
+        assert_eq!(messages.len(), 9);
+        assert_eq!(messages[4].content, "task 2");
+        assert_eq!(messages[5].content, "task 3");
+    }
 }
 
 #[derive(Debug)]

src/channels/feishu.rs

@@ -1931,15 +1931,24 @@ impl FeishuChannel {
             );
         }
 
+        /// Restore all code block placeholders in the given text.
+        fn restore_code_blocks(text: &str, code_blocks: &[String]) -> String {
+            let mut result = text.to_string();
+            for (i, cb) in code_blocks.iter().enumerate() {
+                result = result.replace(&format!("\x00CODE{}\x00", i), cb);
+            }
+            result
+        }
+
         let mut elements: Vec<serde_json::Value> = Vec::new();
         let mut last_end = 0;
 
         for m in patterns.heading_re.find_iter(&protected) {
-            let before = &protected[last_end..m.start()].trim();
+            let before = protected[last_end..m.start()].trim();
             if !before.is_empty() {
                 elements.push(serde_json::json!({
                     "tag": "markdown",
-                    "content": before
+                    "content": restore_code_blocks(before, &code_blocks)
                 }));
             }
 
@@ -1963,14 +1972,9 @@ impl FeishuChannel {
 
         let remaining = protected[last_end..].trim();
         if !remaining.is_empty() {
-            // Restore code blocks
-            let mut final_content = remaining.to_string();
-            for (i, cb) in code_blocks.iter().enumerate() {
-                final_content = final_content.replace(&format!("\x00CODE{}\x00", i), cb);
-            }
             elements.push(serde_json::json!({
                 "tag": "markdown",
-                "content": final_content
+                "content": restore_code_blocks(remaining, &code_blocks)
             }));
         }
 

src/command/adapters/channel.rs

@@ -133,6 +133,11 @@ impl InputAdapter for ChannelInputAdapter {
             return Ok(Some(Command::GetCurrentSession));
         }
 
+        // 解析 /stop 命令 - 停止当前执行的 Agent
+        if trimmed == "/stop" {
+            return Ok(Some(Command::StopExecution));
+        }
+
         // 解析 /help 命令 - 显示所有支持的命令
         if trimmed == "/help" {
             return Ok(Some(Command::Help));

src/command/adapters/cli.rs

@@ -134,6 +134,11 @@ impl InputAdapter for CliInputAdapter {
             return Ok(Some(Command::GetCurrentSession));
         }
 
+        // 解析 /stop 命令 - 停止当前执行的 Agent
+        if trimmed == "/stop" {
+            return Ok(Some(Command::StopExecution));
+        }
+
         // 解析 /help 命令 - 显示所有支持的命令
         if trimmed == "/help" {
             return Ok(Some(Command::Help));

src/command/handlers/mod.rs

@@ -11,6 +11,7 @@ pub mod load_topic;
 pub mod save_session;
 pub mod save_topic;
 pub mod session;
+pub mod stop_execution;
 pub mod switch_topic;
 
 // 导出公共函数供其他模块复用

src/command/handlers/stop_execution.rs

@@ -0,0 +1,57 @@
+use async_trait::async_trait;
+
+use crate::command::context::CommandContext;
+use crate::command::handler::{CommandHandler, CommandMetadata};
+use crate::command::response::{CommandError, CommandResponse, MessageKind};
+use crate::command::Command;
+use crate::gateway::cancel_manager::CancelManager;
+
+/// 处理 StopExecution 命令：按话题取消当前正在执行的 Agent。
+pub struct StopExecutionCommandHandler {
+    cancel_manager: CancelManager,
+}
+
+impl StopExecutionCommandHandler {
+    pub fn new(cancel_manager: CancelManager) -> Self {
+        Self { cancel_manager }
+    }
+}
+
+#[async_trait]
+impl CommandHandler for StopExecutionCommandHandler {
+    fn can_handle(&self, cmd: &Command) -> bool {
+        matches!(cmd, Command::StopExecution)
+    }
+
+    fn metadata(&self) -> Option<CommandMetadata> {
+        Some(CommandMetadata {
+            name: "stop",
+            description: "停止当前话题正在执行的 Agent",
+            usage: "/stop",
+        })
+    }
+
+    async fn handle(
+        &self,
+        _cmd: Command,
+        ctx: CommandContext,
+    ) -> Result<CommandResponse, CommandError> {
+        let topic_id = match ctx.topic_id.as_deref() {
+            Some(id) => id,
+            None => {
+                return Ok(CommandResponse::success(ctx.request_id)
+                    .with_message(MessageKind::Notification, "当前没有活跃的话题，无法停止"));
+            }
+        };
+
+        let cancelled = self.cancel_manager.cancel_by_topic(topic_id).await;
+
+        if cancelled {
+            Ok(CommandResponse::success(ctx.request_id)
+                .with_message(MessageKind::Notification, "正在停止当前任务..."))
+        } else {
+            Ok(CommandResponse::success(ctx.request_id)
+                .with_message(MessageKind::Notification, "当前没有正在执行的任务"))
+        }
+    }
+}

src/command/mod.rs

@@ -52,6 +52,8 @@ pub enum Command {
         channel: String,
         chat_id: String,
     },
+    /// 停止当前正在执行的 Agent
+    StopExecution,
 }
 
 impl Command {
@@ -72,6 +74,7 @@ impl Command {
             Command::LoadTaskMessages { .. } => "load_task_messages",
             Command::ListSchedulerJobs => "list_scheduler_jobs",
             Command::LoadChatMessages { .. } => "load_chat_messages",
+            Command::StopExecution => "stop_execution",
         }
     }
 }

src/gateway/agent_factory.rs

@@ -23,6 +23,8 @@ pub(crate) struct AgentBuildRequest<'a> {
     pub(crate) sender_id: Option<&'a str>,
     pub(crate) message_id: Option<&'a str>,
     pub(crate) provider_config: LLMProviderConfig,
+    /// 取消信号接收端（可选）：Agent 在每次迭代时检查是否被取消
+    pub(crate) cancel_token: Option<tokio::sync::watch::Receiver<()>>,
 }
 
 impl AgentFactory {
@@ -64,7 +66,7 @@ impl AgentFactory {
             let tool_chat_id = request
                 .notification_chat_id
                 .unwrap_or(request.session_chat_id);
-            agent.with_tool_context(ToolContext {
+            let mut agent = agent.with_tool_context(ToolContext {
                 channel_name: Some(request.channel_name.to_string()),
                 sender_id: request.sender_id.map(str::to_string),
                 chat_id: Some(tool_chat_id.to_string()),
@@ -73,7 +75,12 @@ impl AgentFactory {
                 message_id: request.message_id.map(str::to_string),
                 message_seq: None,
                 subagent_description: None,
-            })
+            });
+            // 如果有取消信号接收端，注入 Agent
+            if let Some(token) = request.cancel_token {
+                agent = agent.with_cancel_token(token);
+            }
+            agent
         })
     }
 }

src/gateway/cancel_manager.rs

@@ -0,0 +1,61 @@
+use std::collections::HashMap;
+use std::sync::Arc;
+use tokio::sync::{Mutex, watch};
+
+/// 共享的 Agent 取消注册表。
+///
+/// 每个正在执行的 Agent 在启动前按 topic_id 注册一个 watch::Sender，
+/// 外部（如 /stop 命令）通过 cancel_by_topic() 发送取消信号。
+/// Agent 循环内部通过 watch::Receiver::has_changed() 检测取消。
+///
+/// key 使用 topic_id（UUID），全局唯一，精确到话题级别。
+#[derive(Clone)]
+pub struct CancelManager {
+    tokens: Arc<Mutex<HashMap<String, watch::Sender<()>>>>,
+}
+
+impl CancelManager {
+    pub fn new() -> Self {
+        Self {
+            tokens: Arc::new(Mutex::new(HashMap::new())),
+        }
+    }
+
+    /// 按 topic_id 注册一个取消通道，返回 receiver 供 Agent 持有。
+    ///
+    /// 如果同 topic_id 已有注册，旧 sender 被覆盖并 drop，
+    /// 旧 receiver 将收到通道关闭信号。
+    pub async fn register(&self, topic_id: &str) -> watch::Receiver<()> {
+        let (tx, rx) = watch::channel(());
+        self.tokens.lock().await.insert(topic_id.to_string(), tx);
+        rx
+    }
+
+    /// 按 topic_id 发送取消信号并移除注册条目。
+    ///
+    /// 返回 `true` 表示找到了对应的任务并发送了取消信号，
+    /// 返回 `false` 表示没有找到对应的任务（可能已经完成或从未注册）。
+    pub async fn cancel_by_topic(&self, topic_id: &str) -> bool {
+        if let Some(tx) = self.tokens.lock().await.remove(topic_id) {
+            // send 可能失败（receiver 已被 drop），这不影响语义
+            let _ = tx.send(());
+            true
+        } else {
+            false
+        }
+    }
+
+    /// 按 topic_id 正常完成后清理注册条目（幂等）。
+    ///
+    /// 与 cancel_by_topic() 不同，此方法不发送取消信号，仅移除条目。
+    /// 如果条目已被 cancel_by_topic() 移除，此调用为 no-op。
+    pub async fn remove_by_topic(&self, topic_id: &str) {
+        self.tokens.lock().await.remove(topic_id);
+    }
+}
+
+impl Default for CancelManager {
+    fn default() -> Self {
+        Self::new()
+    }
+}

src/gateway/mod.rs

@@ -1,6 +1,7 @@
 pub mod agent_factory;
 pub mod agent_prompt_provider;
 pub mod agent_task_executor;
+pub mod cancel_manager;
 pub mod cli_session;
 pub mod command;
 pub mod compaction;
@@ -42,6 +43,7 @@ use crate::scheduler::Scheduler;
 use crate::skills::SkillRuntime;
 use crate::tools::task::repository::TaskRepository;
 use agent_task_executor::{AgentTaskExecutor, SchedulerMaintenanceService};
+use cancel_manager::CancelManager;
 use outbound_dispatcher::OutboundDispatcher;
 use processor::InboundProcessor;
 use runtime::build_session_manager_with_sender;
@@ -55,6 +57,7 @@ pub struct GatewayState {
     pub channel_manager: ChannelManager,
     pub bus: Arc<MessageBus>,
     pub task_repository: Arc<dyn TaskRepository>,
+    pub cancel_manager: CancelManager,
 }
 
 impl GatewayState {
@@ -96,12 +99,15 @@ impl GatewayState {
             Some(bus.clone()),
         )?;
 
+        let cancel_manager = CancelManager::new();
+
         Ok(Self {
             config,
             session_manager,
             channel_manager,
             bus,
             task_repository,
+            cancel_manager,
         })
     }
 
@@ -122,7 +128,7 @@ impl GatewayState {
             }
         };
         let inbound_processor =
-            InboundProcessor::new(self.bus.clone(), self.session_manager.clone(), semaphore, provider_config);
+            InboundProcessor::new(self.bus.clone(), self.session_manager.clone(), semaphore, provider_config, self.cancel_manager.clone());
         tokio::spawn(inbound_processor.run());
 
         // Spawn outbound dispatcher

src/gateway/processor.rs

@@ -14,9 +14,11 @@ use crate::command::handlers::load_topic::LoadTopicCommandHandler;
 use crate::command::handlers::save_session::SaveSessionCommandHandler;
 use crate::command::handlers::save_topic::SaveTopicCommandHandler;
 use crate::command::handlers::session::SessionCommandHandler;
+use crate::command::handlers::stop_execution::StopExecutionCommandHandler;
 use crate::command::handlers::switch_topic::SwitchTopicCommandHandler;
 use crate::config::LLMProviderConfig;
 use crate::gateway::agent_prompt_provider::AgentPromptProvider;
+use crate::gateway::cancel_manager::CancelManager;
 use crate::providers::{create_provider, ProviderRuntimeConfig};
 use crate::skills::SkillPromptProvider;
 use crate::storage::persistent_session_id;
@@ -31,6 +33,7 @@ pub struct InboundProcessor {
     semaphore: Arc<Semaphore>,
     provider_config: LLMProviderConfig,
     command_router: Arc<CommandRouter>,
+    cancel_manager: CancelManager,
 }
 
 impl InboundProcessor {
@@ -39,6 +42,7 @@ impl InboundProcessor {
         session_manager: SessionManager,
         semaphore: Arc<Semaphore>,
         provider_config: LLMProviderConfig,
+        cancel_manager: CancelManager,
     ) -> Self {
         // 创建命令路由器并注册处理器
         let mut command_router = CommandRouter::new();
@@ -97,12 +101,18 @@ impl InboundProcessor {
         let metadata = command_router.metadata_arc();
         command_router.register(Box::new(HelpCommandHandler::new(metadata)));
 
+        // 注册 stop_execution 处理器
+        command_router.register(Box::new(StopExecutionCommandHandler::new(
+            cancel_manager.clone(),
+        )));
+
         Self {
             bus,
             session_manager,
             semaphore,
             provider_config,
             command_router: Arc::new(command_router),
+            cancel_manager,
         }
     }
 
@@ -236,6 +246,18 @@ impl InboundProcessor {
             current_topic.clone(),
         ));
 
+        // 保存 channel 和 chat_id 用于后续清理（因 match 中可能 move inbound）
+        let channel = inbound.channel.clone();
+        let chat_id = inbound.chat_id.clone();
+
+        // 按 topic_id 注册取消信号：Agent 构建时通过 Session 消费该 receiver
+        if let Some(ref topic_id) = current_topic {
+            let cancel_rx = self.cancel_manager.register(topic_id).await;
+            self.session_manager
+                .set_agent_cancel_token(&channel, &chat_id, cancel_rx)
+                .await;
+        }
+
         match self
             .session_manager
             .handle_message(
@@ -308,6 +330,11 @@ impl InboundProcessor {
             }
         }
 
+        // 清理取消信号注册（幂等：如果已被 cancel_by_topic() 移除则为 no-op）
+        if let Some(ref topic_id) = current_topic {
+            self.cancel_manager.remove_by_topic(topic_id).await;
+        }
+
         Ok(())
     }
 }

src/gateway/session.rs

@@ -45,6 +45,9 @@ pub struct Session {
     compressor: ContextCompressor,
     history: SessionHistory,
     store: Arc<SessionStore>,
+    /// 等待中的取消信号接收端（按 chat_id 索引）。
+    /// 在 Agent 执行前由外部注入，Agent 构建时消费。
+    pending_cancel_tokens: HashMap<String, tokio::sync::watch::Receiver<()>>,
 }
 
 pub struct BusToolCallEmitter {
@@ -163,6 +166,7 @@ impl Session {
                 skill_events,
             ),
             store,
+            pending_cancel_tokens: HashMap::new(),
         })
     }
 
@@ -179,6 +183,19 @@ impl Session {
         }
     }
 
+    /// 存入待使用的取消信号接收端。
+    ///
+    /// 在 Agent 执行前由处理器调用，Agent 构建时（create_agent）自动消费。
+    /// 每个 chat_id 同时只允许一个 pending token；新 token 会替换旧 token。
+    pub fn set_cancel_receiver(
+        &mut self,
+        chat_id: &str,
+        receiver: tokio::sync::watch::Receiver<()>,
+    ) {
+        self.pending_cancel_tokens
+            .insert(chat_id.to_string(), receiver);
+    }
+
     /// 获取当前话题 ID（指定 chat）
     pub fn current_topic(&self, chat_id: &str) -> Option<&str> {
         self.history.chat_topic(chat_id)
@@ -420,7 +437,7 @@ impl Session {
 
     /// 创建一个临时的 AgentLoop 实例来处理消息
     pub fn create_agent(
-        &self,
+        &mut self,
         chat_id: &str,
         sender_id: Option<&str>,
         message_id: Option<&str>,
@@ -435,13 +452,15 @@ impl Session {
     }
 
     pub fn create_agent_with_provider_config(
-        &self,
+        &mut self,
         session_chat_id: &str,
         notification_chat_id: Option<&str>,
         sender_id: Option<&str>,
         message_id: Option<&str>,
         provider_config: LLMProviderConfig,
     ) -> Result<AgentLoop, AgentError> {
+        // 消费 pending 的取消信号接收端（如果存在）
+        let cancel_token = self.pending_cancel_tokens.remove(session_chat_id);
         self.agent_factory.create(AgentBuildRequest {
             channel_name: &self.channel_name,
             session_chat_id,
@@ -449,6 +468,7 @@ impl Session {
             sender_id,
             message_id,
             provider_config,
+            cancel_token,
         })
     }
 }
@@ -607,6 +627,20 @@ impl SessionManager {
         }
     }
 
+    /// 存入 Agent 取消信号接收端，供 Agent 构建时消费。
+    ///
+    /// 在 Agent 执行前由处理器调用。Agent 在 create_agent() 时自动取出。
+    pub async fn set_agent_cancel_token(
+        &self,
+        channel_name: &str,
+        chat_id: &str,
+        token: tokio::sync::watch::Receiver<()>,
+    ) {
+        if let Some(session) = self.get(channel_name).await {
+            session.lock().await.set_cancel_receiver(chat_id, token);
+        }
+    }
+
     /// 更新最后活跃时间
     pub async fn touch(&self, channel_name: &str) {
         self.lifecycle.touch(channel_name).await;

src/gateway/ws.rs

@@ -17,6 +17,7 @@ use crate::command::handlers::load_task_messages::LoadTaskMessagesCommandHandler
 use crate::command::handlers::load_topic::LoadTopicCommandHandler;
 use crate::command::handlers::save_session::SaveSessionCommandHandler;
 use crate::command::handlers::session::SessionCommandHandler;
+use crate::command::handlers::stop_execution::StopExecutionCommandHandler;
 use crate::command::handlers::switch_topic::SwitchTopicCommandHandler;
 use crate::gateway::agent_prompt_provider::AgentPromptProvider;
 use crate::protocol::{WsInbound, WsOutbound, MediaSummary, parse_inbound, serialize_outbound};
@@ -405,6 +406,10 @@ async fn handle_inbound(
             router.register(Box::new(ListSchedulerJobsCommandHandler::new(store.clone())));
             // 注册 load_chat_messages 处理器
             router.register(Box::new(LoadChatMessagesCommandHandler::new()));
+            // 注册 stop_execution 处理器
+            router.register(Box::new(StopExecutionCommandHandler::new(
+                state.cancel_manager.clone(),
+            )));
 
             // 构建命令上下文
             tracing::debug!(

src/protocol/mod.rs

@@ -187,6 +187,8 @@ pub enum WsOutbound {
     SchedulerJobList {
         jobs: Vec<SchedulerJobSummary>,
     },
+    #[serde(rename = "execution_cancelled")]
+    ExecutionCancelled { message: String },
     #[serde(rename = "pong")]
     Pong,
 }

tests/test_request_format.rs

@@ -155,6 +155,7 @@ fn test_tool_result_outbound_serialization() {
         content: "工具结果: calculator\n\n2".to_string(),
         role: "tool".to_string(),
         subagent_task_id: None,
+        duration_ms: None,
     };
 
     let json = serde_json::to_string(&msg).unwrap();

web/src/App.tsx

@@ -51,6 +51,7 @@ function App() {
     requestTopicList,
     enterSubAgentView,
     exitSubAgentView,
+    handleStop,
   } = useChat()
 
   const { status, sendMessage } = useWebSocket({
@@ -127,6 +128,9 @@ function App() {
           case 'save':
             cmd = { type: 'save_topic', filepath: args[0] || undefined, include_subagents: false }
             break
+          case 'stop':
+            cmd = { type: 'stop_execution' }
+            break
           default:
             alert(`Unknown command: /${command}`)
             return
@@ -147,6 +151,12 @@ function App() {
     [sendMessage, handleMessage, handleCommand, sessionId, chatId, isReadOnly]
   )
 
+  const handleStopExecution = useCallback(() => {
+    const cmd = handleStop()
+    handleCommand(cmd)
+    sendMessage({ type: 'command', payload: JSON.stringify(cmd) })
+  }, [sendMessage, handleCommand, handleStop])
+
   const handleCreateTopic = useCallback(() => {
     if (isReadOnly || !sessionId) {
       return
@@ -415,6 +425,7 @@ function App() {
               }
               onSendMessage={subAgentView || schedulerView ? () => {} : handleSendMessage}
               onNavigateToSubAgent={handleNavigateToSubAgent}
+              onStop={handleStopExecution}
             />
           </div>
         </div>

web/src/components/Chat/ChatContainer.tsx

@@ -9,6 +9,7 @@ interface ChatContainerProps {
   channelName?: string
   onSendMessage: (content: string, attachments: Attachment[]) => void
   onNavigateToSubAgent?: (taskId: string, description: string) => void
+  onStop?: () => void
 }
 
 export function ChatContainer({
@@ -18,6 +19,7 @@ export function ChatContainer({
   channelName,
   onSendMessage,
   onNavigateToSubAgent,
+  onStop,
 }: ChatContainerProps) {
   return (
     <div className="flex h-full flex-col">
@@ -26,6 +28,7 @@ export function ChatContainer({
       </div>
       <MessageInput
         onSend={onSendMessage}
+        onStop={onStop}
         disabled={isLoading}
         isLoading={isLoading}
         isReadOnly={isReadOnly}

web/src/components/Chat/MessageBubble.tsx

@@ -207,7 +207,7 @@ export function MessageBubble({ message, onNavigateToSubAgent }: MessageBubblePr
     const displayContent = hasResult ? stripToolResultPrefix(message.resultContent!) : ''
 
     const isTaskTool = message.toolName === 'task'
-    const taskResult = isTaskTool && hasResult ? parseTaskResult(message.resultContent!) : null
+    const taskResult = isTaskTool && hasResult ? parseTaskResult(displayContent) : null
     const isSubAgent = !!message.subagentTaskId
     const subagentType = (message.arguments as Record<string, unknown> | null)?.subagent_type as string || 'general'
     const taskDescription = (message.arguments as Record<string, unknown> | null)?.description as string || ''

web/src/components/Chat/MessageInput.tsx

@@ -1,4 +1,4 @@
-import { Send, Loader2, Sparkles, Eye, Paperclip, X, FileIcon, ImageIcon, MusicIcon, VideoIcon } from 'lucide-react'
+import { Send, Loader2, Square, Sparkles, Eye, Paperclip, X, FileIcon, ImageIcon, MusicIcon, VideoIcon } from 'lucide-react'
 import { useState, useRef, useEffect } from 'react'
 import type { Attachment } from '../../types/protocol'
 
@@ -6,6 +6,7 @@ const MAX_FILE_SIZE = 50 * 1024 * 1024 // 50MB
 
 interface MessageInputProps {
   onSend: (content: string, attachments: Attachment[]) => void
+  onStop?: () => void
   disabled?: boolean
   isLoading?: boolean
   placeholder?: string
@@ -29,6 +30,7 @@ function getMediaType(mimeType: string): string {
 
 export function MessageInput({
   onSend,
+  onStop,
   disabled = false,
   isLoading = false,
   placeholder = '输入消息...按 / 查看命令',
@@ -366,18 +368,28 @@ export function MessageInput({
             <Sparkles className="absolute right-3 top-1/2 -translate-y-1/2 h-4 w-4 text-zinc-600 pointer-events-none" />
           </div>
 
-          {/* 发送按钮 */}
-          <button
-            onClick={handleSend}
-            disabled={disabled || (!content.trim() && attachments.length === 0)}
-            className="flex h-10 w-10 shrink-0 items-center justify-center rounded-xl bg-gradient-to-r from-[#00f0ff] to-[#3b82f6] text-white shadow-lg shadow-[#00f0ff]/20 hover:shadow-xl hover:shadow-[#00f0ff]/30 hover:scale-105 disabled:opacity-50 disabled:hover:scale-100 disabled:cursor-not-allowed transition-all"
-          >
-            {disabled ? (
-              <Loader2 className="h-4 w-4 animate-spin" />
-            ) : (
-              <Send className="h-4 w-4" />
-            )}
-          </button>
+          {/* 发送/停止按钮 */}
+          {isLoading && onStop ? (
+            <button
+              onClick={onStop}
+              title="停止执行"
+              className="flex h-10 w-10 shrink-0 items-center justify-center rounded-xl bg-red-500/10 border border-red-500/20 text-red-400 hover:bg-red-500/20 hover:text-red-300 transition-all"
+            >
+              <Square className="h-4 w-4" />
+            </button>
+          ) : (
+            <button
+              onClick={handleSend}
+              disabled={disabled || (!content.trim() && attachments.length === 0)}
+              className="flex h-10 w-10 shrink-0 items-center justify-center rounded-xl bg-gradient-to-r from-[#00f0ff] to-[#3b82f6] text-white shadow-lg shadow-[#00f0ff]/20 hover:shadow-xl hover:shadow-[#00f0ff]/30 hover:scale-105 disabled:opacity-50 disabled:hover:scale-100 disabled:cursor-not-allowed transition-all"
+            >
+              {disabled ? (
+                <Loader2 className="h-4 w-4 animate-spin" />
+              ) : (
+                <Send className="h-4 w-4" />
+              )}
+            </button>
+          )}
         </div>
 
         {/* 提示 */}

web/src/hooks/useChat.ts

@@ -72,6 +72,9 @@ interface UseChatReturn {
   schedulerView: SchedulerJobView | null
   enterSchedulerJobView: (lookup: SchedulerJobSessionLookup, jobId: string, description: string) => Command
   exitSchedulerJobView: () => void
+
+  // 停止当前 Agent 执行
+  handleStop: () => Command
 }
 
 interface SubAgentView {
@@ -257,8 +260,8 @@ export function useChat(): UseChatReturn {
       const msgSubagentTaskId = getSubagentTaskId(message)
       if (msgSubagentTaskId && msgSubagentTaskId === currentSubAgentView.taskId) {
         appendToSubAgentViewMessage(message)
+        return
       }
-      return
     }
 
     // In main view, skip sub-agent messages (they belong to sub-agent view).
@@ -410,6 +413,21 @@ export function useChat(): UseChatReturn {
         break
       }
 
+      case 'execution_cancelled': {
+        setMessages((prev) => [
+          ...prev,
+          {
+            id: generateMessageId(),
+            role: 'assistant',
+            content: (message as { type: 'execution_cancelled'; message: string }).message,
+            timestamp: Date.now(),
+            type: 'message',
+          },
+        ])
+        setIsLoading(false)
+        break
+      }
+
       case 'error': {
         setMessages((prev) => [
           ...prev,
@@ -568,6 +586,10 @@ export function useChat(): UseChatReturn {
     setSchedulerView(null)
   }, [])
 
+  const handleStop = useCallback((): Command => {
+    return { type: 'stop_execution' }
+  }, [])
+
   // Memoize messages: sub-agent view > scheduler view > main
   const resolvedMessages = useMemo(() => {
     if (subAgentView) {
@@ -612,5 +634,6 @@ export function useChat(): UseChatReturn {
     schedulerView,
     enterSchedulerJobView,
     exitSchedulerJobView,
+    handleStop,
   }
 }

web/src/types/protocol.ts

@@ -192,6 +192,11 @@ export interface TaskMessagesLoaded {
   summary?: string
 }
 
+export interface ExecutionCancelled {
+  type: 'execution_cancelled'
+  message: string
+}
+
 export type WsOutbound =
   | AssistantResponse
   | ToolCall
@@ -207,6 +212,7 @@ export type WsOutbound =
   | ChannelList
   | TaskMessagesLoaded
   | SchedulerJobList
+  | ExecutionCancelled
   | Pong
 
 // ============================================================================
@@ -284,6 +290,10 @@ export interface LoadChatMessagesCommand {
   chat_id: string
 }
 
+export interface StopExecutionCommand {
+  type: 'stop_execution'
+}
+
 export type Command =
   | CreateSessionCommand
   | ListSessionsCommand
@@ -299,6 +309,7 @@ export type Command =
   | LoadTaskMessagesCommand
   | ListSchedulerJobsCommand
   | LoadChatMessagesCommand
+  | StopExecutionCommand
 
 // ============================================================================
 // UI Types