feat: 添加定时任务执行系统提示，优化agent_task作业的提示描述，避免重复调度时间

src/gateway/session.rs

@@ -33,6 +33,7 @@ const MANAGED_AGENT_MEMORY_TITLE: &str = "## 用户记忆摘要";
 const MEMORY_MAINTENANCE_SYSTEM_PROMPT: &str =
     include_str!("memory_maintenance_system_prompt.md");
 const MEMORY_MAINTENANCE_RETRY_DELAYS_MS: &[u64] = &[1_000, 3_000];
+const SCHEDULED_TASK_EXECUTION_SYSTEM_PROMPT: &str = "系统说明：当前输入来自一次已经触发的定时任务执行。你现在需要执行任务内容本身，而不是创建、修改、恢复、暂停或查询新的定时任务。除非当前任务内容明确要求管理调度器，否则不要调用任何定时任务管理工具；像“每小时”、“每天”、“cron”、“定时”等词，只应视为任务背景，不应再解释为新的建任务请求。";
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 enum MemoryMaintenanceCategory {
@@ -1481,15 +1482,15 @@ impl SessionManager {
             session_guard.ensure_chat_loaded(chat_id)?;
             session_guard.ensure_agent_prompt_before_user_message(chat_id)?;
 
-            if let Some(system_prompt) = options.system_prompt.as_deref() {
-                session_guard.append_persisted_message(
-                    chat_id,
-                    ChatMessage::system_with_context(
-                        system_prompt,
-                        Some(SYSTEM_CONTEXT_SCHEDULED_PROMPT.to_string()),
-                    ),
-                )?;
-            }
+            let scheduled_system_prompt =
+                compose_scheduled_task_system_prompt(options.system_prompt.as_deref());
+            session_guard.append_persisted_message(
+                chat_id,
+                ChatMessage::system_with_context(
+                    &scheduled_system_prompt,
+                    Some(SYSTEM_CONTEXT_SCHEDULED_PROMPT.to_string()),
+                ),
+            )?;
 
             let user_message = session_guard.create_user_message(prompt, Vec::new());
             let user_message_id = user_message.id.clone();
@@ -1575,6 +1576,17 @@ fn should_display_message_to_user(show_tool_results: bool, message: &ChatMessage
         )
 }
 
+fn compose_scheduled_task_system_prompt(system_prompt: Option<&str>) -> String {
+    match system_prompt.map(str::trim).filter(|value| !value.is_empty()) {
+        Some(system_prompt) => format!(
+            "{}\n\n任务专属要求：{}",
+            SCHEDULED_TASK_EXECUTION_SYSTEM_PROMPT,
+            system_prompt
+        ),
+        None => SCHEDULED_TASK_EXECUTION_SYSTEM_PROMPT.to_string(),
+    }
+}
+
 fn select_provider_config(
     default_provider_config: &LLMProviderConfig,
     provider_configs: &HashMap<String, LLMProviderConfig>,
@@ -1936,6 +1948,66 @@ mod tests {
         assert!(default_outbound[0].content.contains("default-model"));
     }
 
+    #[tokio::test]
+    async fn test_run_scheduled_agent_task_persists_execution_guard_prompt() {
+        let base_url = start_mock_openai_server().await;
+        let provider_config = LLMProviderConfig {
+            provider_type: "openai".to_string(),
+            name: "default-provider".to_string(),
+            base_url,
+            api_key: "test-key".to_string(),
+            extra_headers: HashMap::new(),
+            model_id: "default-model".to_string(),
+            temperature: Some(0.0),
+            max_tokens: Some(32),
+            model_extra: HashMap::new(),
+            max_tool_iterations: 1,
+            llm_timeout_secs: 30,
+            tool_result_max_chars: 20_000,
+            context_tool_result_trim_chars: 20_000,
+        };
+
+        let session_manager = SessionManager::new(
+            4,
+            100,
+            false,
+            provider_config.clone(),
+            HashMap::from([("default".to_string(), provider_config)]),
+            Arc::new(SkillRuntime::default()),
+        )
+        .unwrap();
+
+        session_manager
+            .run_scheduled_agent_task(
+                "feishu",
+                "chat-guard",
+                "每小时执行以下流程：检查邮箱并同步待办",
+                ScheduledAgentTaskOptions {
+                    fresh_session: true,
+                    system_prompt: Some("你是邮箱待办同步助手。".to_string()),
+                    ..Default::default()
+                },
+            )
+            .await
+            .unwrap();
+
+        let session = session_manager.get("feishu").await.unwrap();
+        let session_guard = session.lock().await;
+        let persisted_messages = session_guard
+            .store
+            .load_messages(&session_guard.persistent_session_id("chat-guard"))
+            .unwrap();
+
+        let scheduled_prompt = persisted_messages
+            .iter()
+            .find(|message| message.has_system_context(SYSTEM_CONTEXT_SCHEDULED_PROMPT))
+            .expect("missing scheduled system prompt");
+
+        assert!(scheduled_prompt.content.contains("已经触发的定时任务执行"));
+        assert!(scheduled_prompt.content.contains("不要调用任何定时任务管理工具"));
+        assert!(scheduled_prompt.content.contains("你是邮箱待办同步助手。"));
+    }
+
     #[tokio::test]
     async fn test_summarize_memory_maintenance_for_scope_uses_model_output() {
         let base_url = start_mock_openai_server().await;

src/providers/openai.rs

@@ -36,6 +36,13 @@ pub struct OpenAIProvider {
     model_extra: HashMap<String, serde_json::Value>,
 }
 
+#[derive(Deserialize)]
+#[serde(untagged)]
+enum OAIFunctionArguments {
+    Json(Value),
+    String(String),
+}
+
 impl OpenAIProvider {
     pub fn new(
         name: String,
@@ -67,6 +74,23 @@ impl OpenAIProvider {
         }
     }
 
+    fn uses_json_tool_arguments(&self) -> bool {
+        self.model_extra
+            .get("tool_call_arguments_json")
+            .and_then(|value| value.as_bool())
+            .unwrap_or(false)
+    }
+
+    fn serialize_tool_arguments(&self, arguments: &Value) -> Value {
+        if self.uses_json_tool_arguments() {
+            arguments.clone()
+        } else {
+            Value::String(
+                serde_json::to_string(arguments).unwrap_or_else(|_| "null".to_string()),
+            )
+        }
+    }
+
     fn build_request_body(&self, request: &ChatCompletionRequest) -> Value {
         let mut body = json!({
             "model": self.model_id,
@@ -88,7 +112,7 @@ impl OpenAIProvider {
                                 "type": "function",
                                 "function": {
                                     "name": call.name,
-                                    "arguments": serde_json::to_string(&call.arguments).unwrap_or_else(|_| "null".to_string())
+                                    "arguments": self.serialize_tool_arguments(&call.arguments)
                                 }
                             })).collect::<Vec<_>>()
                         })
@@ -170,7 +194,7 @@ struct OpenAIToolCall {
 #[derive(Deserialize)]
 struct OAIFunction {
     name: String,
-    arguments: String,
+    arguments: OAIFunctionArguments,
 }
 
 #[derive(Deserialize, Default)]
@@ -260,7 +284,12 @@ impl LLMProvider for OpenAIProvider {
             .map(|tc| ToolCall {
                 id: tc.id.clone(),
                 name: tc.function.name.clone(),
-                arguments: serde_json::from_str(&tc.function.arguments).unwrap_or(serde_json::Value::Null),
+                arguments: match &tc.function.arguments {
+                    OAIFunctionArguments::Json(arguments) => arguments.clone(),
+                    OAIFunctionArguments::String(arguments) => {
+                        serde_json::from_str(arguments).unwrap_or(serde_json::Value::Null)
+                    }
+                },
             })
             .collect();
 
@@ -339,6 +368,48 @@ mod tests {
         assert_eq!(tool_calls[0]["function"]["arguments"], "{\"expression\":\"1+1\"}");
     }
 
+    #[test]
+    fn test_build_request_body_uses_json_tool_arguments_when_enabled() {
+        let provider = OpenAIProvider::new(
+            "test".to_string(),
+            "key".to_string(),
+            "https://example.com/v1".to_string(),
+            HashMap::new(),
+            120,
+            "gpt-test".to_string(),
+            None,
+            None,
+            HashMap::from([(
+                "tool_call_arguments_json".to_string(),
+                Value::Bool(true),
+            )]),
+        );
+
+        let request = ChatCompletionRequest {
+            messages: vec![Message {
+                role: "assistant".to_string(),
+                content: vec![ContentBlock::text("calling tool")],
+                reasoning_content: None,
+                tool_call_id: None,
+                name: None,
+                tool_calls: Some(vec![ToolCall {
+                    id: "call_1".to_string(),
+                    name: "calculator".to_string(),
+                    arguments: json!({"expression": "1+1"}),
+                }]),
+            }],
+            temperature: None,
+            max_tokens: None,
+            tools: None,
+        };
+
+        let body = provider.build_request_body(&request);
+        let messages = body["messages"].as_array().unwrap();
+        let tool_calls = messages[0]["tool_calls"].as_array().unwrap();
+
+        assert_eq!(tool_calls[0]["function"]["arguments"], json!({"expression": "1+1"}));
+    }
+
     #[test]
     fn test_build_request_body_includes_assistant_reasoning_content() {
         let provider = OpenAIProvider::new(
@@ -395,4 +466,37 @@ mod tests {
 
         assert_eq!(response.choices[0].message.reasoning_content.as_deref(), Some("hidden reasoning"));
     }
+
+    #[test]
+    fn test_openai_response_parses_json_tool_arguments() {
+        let response: OpenAIResponse = serde_json::from_value(json!({
+            "id": "resp_1",
+            "model": "gpt-test",
+            "choices": [{
+                "message": {
+                    "content": "",
+                    "tool_calls": [{
+                        "id": "call_1",
+                        "function": {
+                            "name": "scheduler_manage",
+                            "arguments": {"action": "list"}
+                        }
+                    }]
+                }
+            }],
+            "usage": {
+                "prompt_tokens": 1,
+                "completion_tokens": 1,
+                "total_tokens": 2
+            }
+        }))
+        .unwrap();
+
+        match &response.choices[0].message.tool_calls[0].function.arguments {
+            OAIFunctionArguments::Json(arguments) => {
+                assert_eq!(arguments, &json!({"action": "list"}));
+            }
+            OAIFunctionArguments::String(_) => panic!("expected JSON tool arguments"),
+        }
+    }
 }

src/tools/scheduler_manage.rs

@@ -31,10 +31,25 @@ impl Tool for SchedulerManageTool {
     }
 
     fn description(&self) -> &str {
-        "Manage DB-backed scheduled jobs. Supports actions: list, get, put, delete, pause, resume. Jobs persist in SQLite and are executed by the scheduler runtime."
+        "Manage DB-backed scheduled jobs. Supports actions: list, get, put, delete, pause, resume. Jobs persist in SQLite and are executed by the scheduler runtime. When creating agent_task jobs, keep prompt/system_prompt focused on the work to perform; do not restate execution times unless the task logic truly depends on them, because the trigger already controls timing."
     }
 
     fn parameters_schema(&self) -> serde_json::Value {
+        let mut allowed_agents = self
+            .known_agents
+            .iter()
+            .cloned()
+            .collect::<Vec<_>>();
+        allowed_agents.sort();
+        let agent_hint = if allowed_agents.is_empty() {
+            "agent_task payload.agent may be omitted or set to 'default'.".to_string()
+        } else {
+            format!(
+                "agent_task payload.agent may be omitted, set to 'default', or use one of configured agents: {}.",
+                allowed_agents.join(", ")
+            )
+        };
+
         json!({
             "type": "object",
             "properties": {
@@ -63,7 +78,7 @@ impl Tool for SchedulerManageTool {
                 },
                 "payload": {
                     "type": "object",
-                    "description": "Job payload. agent_task supports prompt, agent, fresh_session, system_prompt, sender_id, metadata. outbound_message expects content. internal_event expects event."
+                    "description": format!("Job payload. agent_task supports prompt, agent, fresh_session, system_prompt, sender_id, metadata. For agent_task, write prompt/system_prompt as execution instructions and avoid repeating schedule phrases or execution times such as 每天9点 or 每小时 unless the task itself must reason about time. {} outbound_message expects content. internal_event expects event.", agent_hint)
                 },
                 "max_runs": {
                     "type": ["integer", "null"]
@@ -83,6 +98,18 @@ impl Tool for SchedulerManageTool {
         context: &crate::tools::ToolContext,
         args: serde_json::Value,
     ) -> anyhow::Result<ToolResult> {
+        if args.is_null() {
+            return Ok(error_result(
+                "Missing required parameters: scheduler_manage expects a JSON object like {\"action\":\"list\"}",
+            ));
+        }
+
+        if !args.is_object() {
+            return Ok(error_result(
+                "Invalid parameters: scheduler_manage expects a JSON object",
+            ));
+        }
+
         let action = match args.get("action").and_then(|value| value.as_str()) {
             Some(action) => action,
             None => return Ok(error_result("Missing required parameter: action")),
@@ -263,7 +290,28 @@ fn validate_agent_task_payload(payload: &serde_json::Value, known_agents: &HashS
         return Ok(());
     }
 
-    anyhow::bail!("Unknown agent '{}' for agent_task payload.agent", normalized)
+    anyhow::bail!(unknown_agent_message(normalized, known_agents))
+}
+
+fn unknown_agent_message(agent_name: &str, known_agents: &HashSet<String>) -> String {
+    let mut configured_agents = known_agents.iter().cloned().collect::<Vec<_>>();
+    configured_agents.sort();
+
+    let configured_hint = if configured_agents.is_empty() {
+        "No named agents are configured; use payload.agent='default' or omit payload.agent.".to_string()
+    } else {
+        format!(
+            "payload.agent must be omitted, set to 'default', or use one of configured agents: default, {}.",
+            configured_agents.join(", ")
+        )
+    };
+
+    format!(
+        "Unknown agent '{}' for agent_task payload.agent. {} '{}' is not an agent. If you mean a skill, do not put it in payload.agent.",
+        agent_name,
+        configured_hint,
+        agent_name,
+    )
 }
 
 fn validate_outbound_message_payload(payload: &serde_json::Value) -> anyhow::Result<()> {
@@ -524,6 +572,66 @@ mod tests {
 
         assert!(put_result.is_err());
         let error = put_result.err().unwrap().to_string();
-        assert!(error.contains("Unknown agent 'missing-agent'"));
+        assert!(error.contains("Unknown agent 'missing-agent' for agent_task payload.agent"));
+        assert!(error.contains("payload.agent must be omitted, set to 'default', or use one of configured agents: default, planner"));
+        assert!(error.contains("If you mean a skill, do not put it in payload.agent"));
+    }
+
+    #[tokio::test]
+    async fn test_scheduler_manage_accepts_default_agent() {
+        let store = Arc::new(SessionStore::in_memory().unwrap());
+        let tool = SchedulerManageTool::new(store, HashSet::from(["planner".to_string()]));
+
+        let put_result = tool
+            .execute(json!({
+                "action": "put",
+                "id": "agent.default_summary",
+                "kind": "agent_task",
+                "schedule": {
+                    "type": "cron",
+                    "expression": "0 9 * * *"
+                },
+                "target": {
+                    "channel": "feishu",
+                    "chat_id": "oc_demo"
+                },
+                "payload": {
+                    "prompt": "请总结今天待办",
+                    "agent": "default"
+                }
+            }))
+            .await
+            .unwrap();
+
+        assert!(put_result.success);
+    }
+
+    #[tokio::test]
+    async fn test_scheduler_manage_rejects_null_args_locally() {
+        let store = Arc::new(SessionStore::in_memory().unwrap());
+        let tool = SchedulerManageTool::new(store, HashSet::new());
+
+        let result = tool.execute(serde_json::Value::Null).await.unwrap();
+
+        assert!(!result.success);
+        assert_eq!(
+            result.error.as_deref(),
+            Some("Missing required parameters: scheduler_manage expects a JSON object like {\"action\":\"list\"}")
+        );
+    }
+
+    #[test]
+    fn test_scheduler_manage_schema_advises_against_repeating_schedule_in_agent_task_prompt() {
+        let store = Arc::new(SessionStore::in_memory().unwrap());
+        let tool = SchedulerManageTool::new(store, HashSet::new());
+
+        let schema = tool.parameters_schema();
+        let payload_description = schema["properties"]["payload"]["description"]
+            .as_str()
+            .unwrap();
+
+        assert!(payload_description.contains("avoid repeating schedule phrases or execution times"));
+        assert!(payload_description.contains("每天9点"));
+        assert!(payload_description.contains("每小时"));
     }
 }