feat: add system tools and state updates

backend/db/models.py

@@ -154,6 +154,8 @@ class Assistant(Base):
     enable_interrupt: Mapped[bool] = mapped_column(Boolean, default=True)
     turn_config: Mapped[dict] = mapped_column(JSON, default=dict)
     startup: Mapped[dict] = mapped_column(JSON, default=dict)
+    # Prompt 助手级系统工具；Workflow 的权限保存在各 Agent 节点中。
+    system_tools: Mapped[list] = mapped_column(JSON, default=list)
     vision_enabled: Mapped[bool] = mapped_column(Boolean, default=False)
     vision_model_resource_id: Mapped[str | None] = mapped_column(
         String(40),

backend/db/session.py

@@ -54,12 +54,13 @@ async def sync_default_tools() -> None:
             "id": "tool_end_call_default",
             "name": "结束对话",
             "function_name": "end_call",
-            "type": "end_call",
+            "type": "system",
             "description": "当用户明确要求结束对话，或任务已完成时调用。",
             "definition": {
                 "schema_version": 1,
-                "type": "end_call",
+                "type": "system",
                 "config": {
+                    "kind": "end_conversation",
                     "message_type": "none",
                     "custom_message": "",
                     "capture_reason": True,

backend/migrations/versions/20260804_0010_add_assistant_system_tools.py

@@ -0,0 +1,32 @@
+"""add assistant system tools
+
+Revision ID: 20260804_0010
+Revises: 20260801_0009
+"""
+
+from collections.abc import Sequence
+
+from alembic import op
+import sqlalchemy as sa
+
+
+revision: str = "20260804_0010"
+down_revision: str | Sequence[str] | None = "20260801_0009"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    op.add_column(
+        "assistants",
+        sa.Column(
+            "system_tools",
+            sa.JSON(),
+            server_default=sa.text("'[]'"),
+            nullable=False,
+        ),
+    )
+
+
+def downgrade() -> None:
+    op.drop_column("assistants", "system_tools")

backend/migrations/versions/20260804_0011_tool_end_call_to_system.py

@@ -0,0 +1,44 @@
+"""move end conversation tools into the system category
+
+Revision ID: 20260804_0011
+Revises: 20260804_0010
+"""
+
+from collections.abc import Sequence
+
+from alembic import op
+
+
+revision: str = "20260804_0011"
+down_revision: str | Sequence[str] | None = "20260804_0010"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+
+def upgrade() -> None:
+    op.execute(
+        """
+        UPDATE tools
+        SET type = 'system',
+            definition = jsonb_set(
+                jsonb_set(definition, '{type}', '"system"'::jsonb),
+                '{config,kind}',
+                '"end_conversation"'::jsonb,
+                true
+            )
+        WHERE type = 'end_call'
+        """
+    )
+
+
+def downgrade() -> None:
+    op.execute(
+        """
+        UPDATE tools
+        SET type = 'end_call',
+            definition = (definition #- '{config,kind}')
+                || '{"type":"end_call"}'::jsonb
+        WHERE type = 'system'
+          AND definition #>> '{config,kind}' = 'end_conversation'
+        """
+    )

backend/models.py

@@ -114,6 +114,8 @@ class AssistantConfig(BaseModel):
     # every item in ``tools``.
     tools: list[RuntimeTool] = Field(default_factory=list)
     llm_tool_ids: list[str] | None = None
+    # 助手级系统工具仅供 Prompt Pipeline；Workflow 在 Agent 节点中配置。
+    system_tools: list[str] = Field(default_factory=list)
     knowledge_base_id: str | None = None
     knowledge_base_name: str = ""
     knowledge_base_description: str = ""

backend/routes/assistants.py

@@ -36,6 +36,35 @@ def _validate_workflow(body: AssistantUpsert) -> None:
         return
     body.graph = normalize_graph(body.graph or {})
     errors = validate_graph(body.graph)
+    declared_variables = set(body.dynamic_variable_definitions)
+    for node in body.graph.get("nodes") or []:
+        node_id = str(node.get("id") or "")
+        node_type = node.get("type")
+        data = node.get("data") or {}
+        if node_type == "update_state":
+            unknown = sorted(
+                set((data.get("assignments") or {}).keys()) - declared_variables
+            )
+            if unknown:
+                errors.append(
+                    f"Update State 节点 {node_id} 引用了未声明变量:"
+                    + ",".join(unknown)
+                )
+        elif node_type == "agent":
+            authorized = set(data.get("stateVariableNames") or [])
+            unknown = sorted(authorized - declared_variables)
+            if unknown:
+                errors.append(
+                    f"Agent 节点 {node_id} 授权了未声明变量:"
+                    + ",".join(unknown)
+                )
+            if (
+                "update_state" in (data.get("systemTools") or [])
+                and not authorized
+            ):
+                errors.append(
+                    f"Agent 节点 {node_id} 启用更新状态工具时必须授权至少一个变量"
+                )
     if errors:
         raise HTTPException(400, "工作流校验失败:" + ";".join(errors))
     # Graph settings are the source of truth. The flat flag is only a session
@@ -283,6 +312,7 @@ async def _to_out(session: AsyncSession, assistant: Assistant) -> AssistantOut:
         enable_interrupt=assistant.enable_interrupt,
         turn_config=assistant.turn_config or {},
         startup=assistant.startup or {},
+        system_tools=assistant.system_tools or [],
         vision_enabled=assistant.vision_enabled,
         vision_model_resource_id=assistant.vision_model_resource_id,
         model_resource_ids=await _resource_ids(session, assistant.id),
@@ -359,6 +389,7 @@ async def duplicate_assistant(
         enable_interrupt=source.enable_interrupt,
         turn_config=dict(source.turn_config or {}),
         startup=dict(source.startup or {}),
+        system_tools=list(source.system_tools or []),
         vision_enabled=source.vision_enabled,
         vision_model_resource_id=source.vision_model_resource_id,
         knowledge_base_id=source.knowledge_base_id,

backend/schemas.py

@@ -19,7 +19,7 @@ ModelType = Literal["LLM", "ASR", "TTS", "Realtime", "Embedding", "Agent"]
 AssistantType = Literal["prompt", "workflow", "dify", "fastgpt", "opencode"]
 TurnEndStrategy = Literal["silence", "smart_turn"]
 KnowledgeRetrievalMode = Literal["automatic", "on_demand"]
-ToolType = Literal["end_call", "http", "mcp", "client"]
+ToolType = Literal["system", "http", "mcp", "client"]
 ToolStatus = Literal["active", "archived", "draft"]
 McpServerStatus = Literal["active", "archived", "draft"]
 McpTransport = Literal["streamable_http", "sse"]
@@ -30,6 +30,12 @@ ClientToolResponseWaitMode = Literal["timeout", "session"]
 DynamicVariableType = Literal["string", "number", "boolean"]
 PromptEntryMode = Literal["wait_user", "generate"]
 PromptOpeningMode = Literal["interruptible", "playback", "confirmation"]
+SystemToolKind = Literal[
+    "end_conversation",
+    "update_state",
+    "skip_turn",
+    "request_human_handoff",
+]
 
 # 外部应用类型:其 config.apiKey 是该助手私有密钥,读时打码 / 写时哨兵
 EXTERNAL_TYPES = {"dify", "fastgpt", "opencode"}
@@ -153,6 +159,8 @@ class AssistantUpsert(CamelModel):
     startup: StartupConfig = Field(default_factory=StartupConfig)
     vision_enabled: bool = False
     vision_model_resource_id: str | None = None
+    # 内置系统工具开关(仅 prompt 类型可用,类似 ElevenLabs Agent 的系统工具)。
+    system_tools: list[SystemToolKind] = Field(default_factory=list, max_length=4)
 
     model_resource_ids: dict[ModelType, str] = Field(default_factory=dict)
     knowledge_base_id: str | None = None
@@ -191,6 +199,8 @@ class AssistantUpsert(CamelModel):
         for field in ("prompt", "api_url", "api_key", "app_id"):
             if field not in allowed:
                 setattr(self, field, "")
+        if self.type != "prompt":
+            self.system_tools = []
         if "graph" not in allowed:
             self.graph = {}
         if self.type == "workflow":
@@ -210,6 +220,15 @@ class AssistantUpsert(CamelModel):
         # 外部托管大脑只能 cascade,拦住不兼容的 realtime
         if self.runtime_mode == "realtime" and self.type not in REALTIME_CAPABLE_TYPES:
             raise ValueError(f"类型 {self.type} 不支持 realtime 运行模式")
+        if self.type == "prompt":
+            self.system_tools = list(dict.fromkeys(self.system_tools))
+            if self.runtime_mode == "realtime" and self.system_tools:
+                raise ValueError("Prompt Realtime 模式暂不支持系统工具")
+            if (
+                "update_state" in self.system_tools
+                and not self.dynamic_variable_definitions
+            ):
+                raise ValueError("启用更新状态工具前必须声明至少一个动态变量")
         return self
 
 
@@ -250,7 +269,8 @@ class ToolParameter(CamelModel):
     required: bool = True
 
 
-class EndCallToolConfig(CamelModel):
+class SystemToolConfig(CamelModel):
+    kind: Literal["end_conversation"] = "end_conversation"
     message_type: Literal["none", "custom"] = "none"
     custom_message: str = ""
     capture_reason: bool = True
@@ -275,10 +295,10 @@ class HttpToolConfig(CamelModel):
         return value
 
 
-class EndCallToolDefinition(CamelModel):
+class SystemToolDefinition(CamelModel):
     schema_version: int = 1
-    type: Literal["end_call"] = "end_call"
-    config: EndCallToolConfig = Field(default_factory=EndCallToolConfig)
+    type: Literal["system"] = "system"
+    config: SystemToolConfig = Field(default_factory=SystemToolConfig)
 
 
 class HttpToolDefinition(CamelModel):
@@ -326,7 +346,7 @@ class McpToolDefinition(CamelModel):
 
 ToolDefinition = Annotated[
     Union[
-        EndCallToolDefinition,
+        SystemToolDefinition,
         HttpToolDefinition,
         ClientToolDefinition,
         McpToolDefinition,

backend/services/brains/prompt_brain.py

@@ -43,14 +43,14 @@ from services.message_stage import (
     MessageStageRunner,
     MessageStageSpec,
 )
-from services.runtime_variables import DynamicVariableStore
+from services.runtime_variables import DynamicVariableError, DynamicVariableStore
+from services.system_tools import SYSTEM_TOOL_KINDS, state_update_properties
 from services.tool_executor import ToolExecutionError, ToolExecutor
 from services.tool_policy import policy_for_tool
 
 
 PREFLIGHT_TIMEOUT_SECONDS = 30
 
-
 class PromptBrain(BaseBrain):
     spec = BrainSpec(
         type="prompt",
@@ -123,22 +123,37 @@ class PromptBrain(BaseBrain):
             set(cfg.llm_tool_ids) if cfg.llm_tool_ids is not None else None
         )
         schemas: list[FunctionSchema] = []
+        registered_names: set[str] = set()
         for tool in cfg.tools:
             if llm_tool_ids is not None and tool.id not in llm_tool_ids:
                 continue
-            if tool.type == "end_call":
+            if tool.type == "system":
                 schema, handler = self._make_end_call_tool(tool, runtime)
             elif tool.type in {"http", "mcp", "client"}:
                 schema, handler = self._make_remote_tool(tool, runtime)
             else:
                 continue
             schemas.append(schema)
+            registered_names.add(schema.name)
             policy = policy_for_tool(tool)
             runtime.llm.register_function(
                 tool.function_name,
                 handler,
                 cancel_on_interruption=policy.cancel_on_interruption,
             )
+        for kind in cfg.system_tools or []:
+            if kind not in SYSTEM_TOOL_KINDS:
+                logger.warning(f"忽略未知系统工具: {kind}")
+                continue
+            schema, handler = self._make_system_tool(kind, runtime)
+            if schema.name in registered_names:
+                logger.warning(
+                    f"跳过系统工具 {schema.name}: 与已绑定工具函数名冲突"
+                )
+                continue
+            registered_names.add(schema.name)
+            schemas.append(schema)
+            runtime.llm.register_function(schema.name, handler)
         runtime.set_tools(schemas)
 
     async def run_preflight(self) -> None:
@@ -582,3 +597,162 @@ class PromptBrain(BaseBrain):
             required=["reason"] if capture_reason else [],
         )
         return schema, end_call
+
+    # ---------- 内置系统工具(助手配置 system_tools 开关) ----------
+
+    def _make_system_tool(self, kind: str, runtime: BrainRuntime):
+        if kind == "end_conversation":
+            return self._make_end_conversation_tool(runtime)
+        if kind == "update_state":
+            return self._make_update_state_tool(runtime)
+        if kind == "skip_turn":
+            return self._make_skip_turn_tool()
+        if kind == "request_human_handoff":
+            return self._make_handoff_tool(runtime)
+        raise ValueError(f"未知系统工具: {kind}")
+
+    def _make_end_conversation_tool(self, runtime: BrainRuntime):
+        """结束本次对话,等待模型已生成的告别语播完后再挂断。"""
+
+        async def end_conversation(params: FunctionCallParams) -> None:
+            reason = str(
+                params.arguments.get("reason") or "end_conversation"
+            ).strip()
+            self._waiting_for_generated_end_speech = True
+            runtime.call_end.begin(reason)
+            await params.result_callback(
+                {"status": "success", "action": "ending_call"},
+                properties=FunctionCallResultProperties(run_llm=False),
+            )
+
+        schema = FunctionSchema(
+            name="end_conversation",
+            description=(
+                "礼貌地结束本次对话。当用户明确告别、表示任务已完成"
+                "或要求挂断时调用。"
+            ),
+            properties={
+                "reason": {
+                    "type": "string",
+                    "description": "结束对话的简短原因。",
+                }
+            },
+            required=[],
+        )
+        return schema, end_conversation
+
+    def _make_update_state_tool(self, runtime: BrainRuntime):
+        """更新已声明的动态变量(会话状态),并让模型继续当前回答。"""
+
+        writable = state_update_properties(self._cfg.dynamic_variable_definitions)
+
+        async def update_state(params: FunctionCallParams) -> None:
+            state = dict(params.arguments or {})
+            try:
+                changed = self._store.assign_declared_many(state)
+            except DynamicVariableError as exc:
+                await params.result_callback(
+                    {"status": "error", "message": f"状态更新失败: {exc}"}
+                )
+                return
+            if changed:
+                self._refresh_prompt()
+                await runtime.queue_frame(
+                    OutputTransportMessageUrgentFrame(
+                        message={
+                            "type": "session-variables",
+                            "reason": "update_state",
+                            "variables": self._store.public_values(),
+                            "changed": changed,
+                        }
+                    )
+                )
+            await params.result_callback(
+                {
+                    "status": "success",
+                    "changed": changed,
+                    "variables": self._store.public_values(),
+                }
+            )
+
+        schema = FunctionSchema(
+            name="update_state",
+            description=(
+                "静默更新本次对话中已经声明并明确列出的动态变量。"
+                "只提交本轮获得或确认的信息，更新后继续当前回答。"
+            ),
+            properties=writable,
+            required=[],
+        )
+        return schema, update_state
+
+    def _make_skip_turn_tool(self):
+        """跳过当前轮次,不生成任何语音回复。"""
+
+        async def skip_turn(params: FunctionCallParams) -> None:
+            reason = str(params.arguments.get("reason") or "").strip()
+            result = {"status": "success", "action": "skip_turn"}
+            if reason:
+                result["reason"] = reason
+            await params.result_callback(
+                result,
+                properties=FunctionCallResultProperties(run_llm=False),
+            )
+
+        schema = FunctionSchema(
+            name="skip_turn",
+            description=(
+                "跳过当前轮次,不生成任何语音回复。"
+                "仅当用户明确要求稍等、话还没说完，或输入可确认只是噪音时调用。"
+            ),
+            properties={
+                "reason": {
+                    "type": "string",
+                    "description": "跳过本轮的原因(可选)。",
+                }
+            },
+            required=[],
+        )
+        return schema, skip_turn
+
+    def _make_handoff_tool(self, runtime: BrainRuntime):
+        """提交人工接管请求；请求完成前保持当前 AI 会话可用。"""
+
+        async def request_human_handoff(params: FunctionCallParams) -> None:
+            reason = str(
+                params.arguments.get("reason") or "human_handoff"
+            ).strip()
+            await runtime.queue_frame(
+                OutputTransportMessageUrgentFrame(
+                    message={
+                        "type": "handoff-requested",
+                        "source": "prompt-system-tool",
+                        "reason": reason,
+                        "message": "用户请求转接人工服务。",
+                    }
+                )
+            )
+            await params.result_callback(
+                {
+                    "status": "requested",
+                    "action": "human_handoff_requested",
+                    "message": "人工接管请求已提交，请告知用户正在等待人工响应。",
+                }
+            )
+
+        schema = FunctionSchema(
+            name="request_human_handoff",
+            description=(
+                "提交人工接管请求。当用户明确要求人工服务、投诉升级或 AI 无法"
+                "解决时调用。该工具只提交请求，不代表人工已经接通；调用后继续"
+                "回复用户并说明正在等待人工响应。"
+            ),
+            properties={
+                "reason": {
+                    "type": "string",
+                    "description": "转接人工的原因。",
+                }
+            },
+            required=[],
+        )
+        return schema, request_human_handoff

backend/services/brains/workflow_brain.py

@@ -56,7 +56,8 @@ from services.message_stage import (
     MessageStageRunner,
     MessageStageSpec,
 )
-from services.runtime_variables import DynamicVariableStore
+from services.runtime_variables import DynamicVariableError, DynamicVariableStore
+from services.system_tools import SYSTEM_TOOL_KINDS, state_update_properties
 from services.tool_executor import ToolExecutionError, ToolExecutor
 from services.tool_policy import policy_for_tool
 from services.workflow.agent import WorkflowAgentStage
@@ -184,6 +185,7 @@ class WorkflowBrain(BaseBrain):
         self._output: WorkflowOutput | None = None
         self._agent_stage: WorkflowAgentStage | None = None
         self._ended = False
+        self._waiting_for_generated_end_speech = False
         self._next_message_token = 1
         self._pending_message: _MessageContinuation | None = None
 
@@ -229,6 +231,7 @@ class WorkflowBrain(BaseBrain):
             runtime=runtime,
         )
         self._ended = False
+        self._waiting_for_generated_end_speech = False
         self._next_message_token = 1
         self._pending_message = None
         self._manager = ConfiguredFlowManager(
@@ -494,18 +497,30 @@ class WorkflowBrain(BaseBrain):
             return None
         return decision.edge
 
+    async def on_assistant_text_start(self, _turn_id: str) -> None:
+        if self._runtime is not None:
+            self._runtime.call_end.begin_response()
+
     async def on_assistant_text_end(
         self,
         _turn_id: str,
         content: str,
         interrupted: bool,
     ) -> None:
-        if not content or interrupted or self._ended:
-            return
-        self._store.record("agent", content, completed_agent_turn=True)
-        self._state.consume_user_turn()
-        if self._engine.node_type(self._state.current_node_id) == "agent":
-            self._state.status = WorkflowStatus.WAITING_USER
+        if content and not interrupted and not self._ended:
+            self._store.record("agent", content, completed_agent_turn=True)
+            self._state.consume_user_turn()
+            if self._engine.node_type(self._state.current_node_id) == "agent":
+                self._state.status = WorkflowStatus.WAITING_USER
+        if (
+            self._waiting_for_generated_end_speech
+            and self._runtime is not None
+            and self._runtime.call_end.ending
+        ):
+            self._waiting_for_generated_end_speech = False
+            await self._runtime.call_end.finish_after_current_speech(
+                has_text=bool(content.strip()) and not interrupted
+            )
 
     async def _refresh_agent_prompt(self, node_id: str) -> None:
         await self._require_agent_stage().refresh_prompt(node_id)
@@ -528,15 +543,43 @@ class WorkflowBrain(BaseBrain):
     ) -> NodeConfig:
         stage = self._engine.agent_stage_config(node_id)
         functions: list[FlowsFunctionSchema] = []
+        registered_names: set[str] = set()
+
+        def append_function(function: FlowsFunctionSchema | None) -> None:
+            if function is None:
+                return
+            function_name = getattr(function, "name", "")
+            if not function_name:
+                # Runtime-provided global functions are opaque in a few
+                # adapters; FlowManager remains responsible for those names.
+                functions.append(function)
+                return
+            if function_name in registered_names:
+                logger.warning(
+                    f"跳过 Agent {node_id} 的函数 {function_name}: 函数名冲突"
+                )
+                return
+            registered_names.add(function_name)
+            functions.append(function)
+
         for tool_id in stage.tool_ids:
             tool = self._tool_by_id.get(str(tool_id))
             if tool and tool.type in {"http", "mcp", "client"}:
-                functions.append(self._flow_tool(tool, node_id))
-        knowledge_function = self._knowledge_function(node_id)
-        if knowledge_function:
-            functions.append(knowledge_function)
+                append_function(self._flow_tool(tool, node_id))
+        append_function(self._knowledge_function(node_id))
         if stage.vision_enabled and self._require_runtime().vision_function:
-            functions.append(self._require_runtime().vision_function)
+            append_function(self._require_runtime().vision_function)
+        for kind in stage.system_tools:
+            if kind not in SYSTEM_TOOL_KINDS:
+                logger.warning(f"忽略 Agent {node_id} 的未知系统工具: {kind}")
+                continue
+            append_function(
+                self._workflow_system_tool(
+                    kind,
+                    node_id=node_id,
+                    state_variable_names=stage.state_variable_names,
+                )
+            )
         return self._require_agent_stage().node_config(
             node_id,
             functions=functions,
@@ -693,6 +736,159 @@ class WorkflowBrain(BaseBrain):
             ),
         )
 
+    def _workflow_system_tool(
+        self,
+        kind: str,
+        *,
+        node_id: str,
+        state_variable_names: tuple[str, ...],
+    ) -> FlowsFunctionSchema:
+        """Build one platform-owned tool scoped to the active Agent node."""
+        if kind == "update_state":
+            return self._workflow_update_state_tool(
+                node_id,
+                state_variable_names=state_variable_names,
+            )
+        if kind == "skip_turn":
+            return self._workflow_skip_turn_tool()
+        if kind == "request_human_handoff":
+            return self._workflow_handoff_tool(node_id)
+        if kind == "end_conversation":
+            return self._workflow_end_conversation_tool()
+        raise ValueError(f"未知系统工具: {kind}")
+
+    def _workflow_update_state_tool(
+        self,
+        node_id: str,
+        *,
+        state_variable_names: tuple[str, ...],
+    ) -> FlowsFunctionSchema:
+        allowed = frozenset(state_variable_names)
+
+        async def handler(args, _flow_manager):
+            values = dict(args or {})
+            unauthorized = sorted(set(values) - allowed)
+            if unauthorized:
+                return {
+                    "status": "error",
+                    "message": "状态变量未获当前节点授权: " + ",".join(unauthorized),
+                }
+            try:
+                changed = self._store.assign_declared_many(values)
+            except DynamicVariableError as exc:
+                return {"status": "error", "message": f"状态更新失败: {exc}"}
+            if changed:
+                await self._emit_variables(
+                    reason="update_state",
+                    node_id=node_id,
+                    changed=changed,
+                )
+                await self._refresh_agent_prompt(node_id)
+            return {
+                "status": "success",
+                "changed": changed,
+                "variables": self._store.public_values(),
+            }
+
+        return FlowsFunctionSchema(
+            name="update_state",
+            description=(
+                "静默更新当前阶段明确授权的动态变量。"
+                "只提交本轮获得或确认的信息，更新后继续当前回答。"
+            ),
+            properties=state_update_properties(
+                self._cfg.dynamic_variable_definitions if self._cfg else {},
+                allowed_names=state_variable_names,
+            ),
+            required=[],
+            handler=handler,
+        )
+
+    @staticmethod
+    def _workflow_skip_turn_tool() -> FlowsFunctionSchema:
+        async def handler(args, _flow_manager):
+            reason = str((args or {}).get("reason") or "").strip()
+            result = {"status": "success", "action": "skip_turn"}
+            if reason:
+                result["reason"] = reason
+            return result
+
+        setattr(handler, "_suppress_followup_llm", True)
+        return FlowsFunctionSchema(
+            name="skip_turn",
+            description=(
+                "跳过当前轮次，不生成任何语音回复。"
+                "仅当用户明确要求稍等、话还没说完，或输入可确认只是噪音时调用。"
+            ),
+            properties={
+                "reason": {
+                    "type": "string",
+                    "description": "跳过本轮的原因（可选）。",
+                }
+            },
+            required=[],
+            handler=handler,
+        )
+
+    def _workflow_handoff_tool(self, node_id: str) -> FlowsFunctionSchema:
+        async def handler(args, _flow_manager):
+            reason = str((args or {}).get("reason") or "human_handoff").strip()
+            await self._require_runtime().queue_frame(
+                OutputTransportMessageUrgentFrame(
+                    message={
+                        "type": "handoff-requested",
+                        "source": "workflow-system-tool",
+                        "nodeId": node_id,
+                        "reason": reason,
+                        "message": "用户请求转接人工服务。",
+                    }
+                )
+            )
+            self._store.values["system__handoff_status"] = "requested"
+            return {
+                "status": "requested",
+                "action": "human_handoff_requested",
+                "message": "人工接管请求已提交，请告知用户正在等待人工响应。",
+            }
+
+        return FlowsFunctionSchema(
+            name="request_human_handoff",
+            description=(
+                "提交人工接管请求。当用户明确要求人工服务、投诉升级或 AI 无法"
+                "解决时调用。该工具只提交请求，不代表人工已经接通；调用后继续"
+                "回复用户并说明正在等待人工响应。"
+            ),
+            properties={
+                "reason": {"type": "string", "description": "转接人工的原因。"}
+            },
+            required=[],
+            handler=handler,
+        )
+
+    def _workflow_end_conversation_tool(self) -> FlowsFunctionSchema:
+        async def handler(args, _flow_manager):
+            reason = str((args or {}).get("reason") or "end_conversation").strip()
+            self._waiting_for_generated_end_speech = True
+            self._require_runtime().call_end.begin(reason)
+            return {"status": "success", "action": "ending_call"}
+
+        setattr(handler, "_suppress_followup_llm", True)
+        return FlowsFunctionSchema(
+            name="end_conversation",
+            description=(
+                "礼貌地结束本次对话。当用户明确告别、表示任务已完成"
+                "或要求挂断时调用。"
+            ),
+            properties={
+                "reason": {
+                    "type": "string",
+                    "description": "结束对话的简短原因。",
+                }
+            },
+            required=[],
+            handler=handler,
+        )
+
     def _flow_managed_transition_config(
         self,
         node_config: NodeConfig,
@@ -838,6 +1034,8 @@ class WorkflowBrain(BaseBrain):
                 outcome = await self._enter_action(node_id)
                 if not outcome.should_route:
                     return self._passive_node_config(node_id, context_messages)
+            elif node_type == "update_state":
+                await self._enter_update_state(node_id)
             elif node_type == "message":
                 self._prepare_message_continuation(
                     node_id,
@@ -862,6 +1060,22 @@ class WorkflowBrain(BaseBrain):
             node_id = str(edge.get("target") or "")
         raise RuntimeError("工作流连续自动跳转超过安全上限")
 
+    async def _enter_update_state(self, node_id: str) -> None:
+        """Apply one deterministic, atomic dynamic-variable update."""
+        self._state.enter(node_id, WorkflowStatus.RUNNING_ACTION)
+        await self._emit_node_active(node_id)
+        raw_assignments = self._engine.data(node_id).get("assignments") or {}
+        rendered = self._store.render_data(raw_assignments)
+        if not isinstance(rendered, dict):
+            raise DynamicVariableError("Update State 节点赋值必须是对象")
+        changed = self._store.assign_declared_many(rendered)
+        if changed:
+            await self._emit_variables(
+                reason="update_state",
+                node_id=node_id,
+                changed=changed,
+            )
+
     def _prepare_message_continuation(
         self,
         node_id: str,

backend/services/config_resolver.py

@@ -266,6 +266,7 @@ async def resolve_runtime_config(
         enableInterrupt=assistant.enable_interrupt,
         turnConfig=assistant.turn_config or {},
         startup=assistant.startup or {},
+        system_tools=assistant.system_tools or [],
         tools=runtime_tools,
         llm_tool_ids=llm_tool_ids,
         knowledge_base_id=assistant.knowledge_base_id,

backend/services/node_specs.py

@@ -11,15 +11,30 @@ from services.message_policy import (
     MESSAGE_CONFIRMATION,
     MESSAGE_PLAYBACK,
 )
+from services.system_tools import SYSTEM_TOOL_KINDS, normalize_system_tools
 
 
 SPEC_VERSION = "3"
-NODE_TYPES = {"start", "agent", "message", "action", "handoff", "end"}
+NODE_TYPES = {
+    "start",
+    "agent",
+    "message",
+    "action",
+    "update_state",
+    "handoff",
+    "end",
+}
 EDGE_MODES = {"llm", "expression", "always"}
 AGENT_ENTRY_MODES = {"wait_user", "generate"}
 ACTION_RESULT_ASSIGNMENT_MODES = {"inherit", "override", "none"}
 ACTION_USER_INPUT_POLICIES = {"queue", "block"}
-AUTOMATIC_NODE_TYPES = {"start", "message", "action", "handoff"}
+AUTOMATIC_NODE_TYPES = {
+    "start",
+    "message",
+    "action",
+    "update_state",
+    "handoff",
+}
 EXPRESSION_OPERATORS = {
     "eq",
     "neq",
@@ -98,6 +113,24 @@ NODE_SPECS: list[dict[str, Any]] = [
             {"key": "name", "label": "节点名称", "type": "text", "default": "Action"},
         ],
     },
+    {
+        "name": "update_state",
+        "displayName": "Update State",
+        "category": "execution_node",
+        "description": "原子更新已声明的动态变量，然后使用新状态继续路由。",
+        "icon": "Braces",
+        "accent": "mint",
+        "addable": True,
+        "constraints": {"minIncoming": 1, "minOutgoing": 0},
+        "fields": [
+            {
+                "key": "name",
+                "label": "节点名称",
+                "type": "text",
+                "default": "Update State",
+            },
+        ],
+    },
     {
         "name": "handoff",
         "displayName": "Handoff",
@@ -160,6 +193,11 @@ def _normalize_agent_data(data: dict[str, Any]) -> None:
     if data.get("entryMode") not in AGENT_ENTRY_MODES:
         data["entryMode"] = "wait_user"
     data.pop("entrySpeech", None)
+    data["systemTools"] = list(normalize_system_tools(data.get("systemTools")))
+    state_names = data.get("stateVariableNames")
+    data["stateVariableNames"] = list(
+        dict.fromkeys(str(name) for name in state_names or [] if str(name))
+    )
     if "inheritGlobalConfig" not in data:
         has_node_overrides = any(
             (
@@ -194,6 +232,12 @@ def _normalize_action_data(data: dict[str, Any]) -> None:
     data.pop("speech", None)
 
 
+def _normalize_update_state_data(data: dict[str, Any]) -> None:
+    """Keep deterministic state updates as one explicit assignment object."""
+    assignments = data.get("assignments")
+    data["assignments"] = dict(assignments) if isinstance(assignments, dict) else {}
+
+
 def _normalize_message_data(data: dict[str, Any]) -> None:
     """Fill the small built-in Message contract used by runtime and editor."""
     data.setdefault("speech", "")
@@ -246,6 +290,8 @@ def normalize_graph(graph: dict[str, Any] | None) -> dict[str, Any]:
                 _normalize_message_data(data)
             elif node.get("type") == "action":
                 _normalize_action_data(data)
+            elif node.get("type") == "update_state":
+                _normalize_update_state_data(data)
         return source
 
     nodes = source.get("nodes") or []
@@ -262,6 +308,7 @@ def normalize_graph(graph: dict[str, Any] | None) -> dict[str, Any]:
         "agent": "agent",
         "message": "message",
         "action": "action",
+        "update_state": "update_state",
         "handoff": "handoff",
         "end": "end",
     }
@@ -283,6 +330,8 @@ def normalize_graph(graph: dict[str, Any] | None) -> dict[str, Any]:
             _normalize_message_data(data)
         elif new_type == "action":
             _normalize_action_data(data)
+        elif new_type == "update_state":
+            _normalize_update_state_data(data)
         elif new_type == "start":
             prompt = str(data.pop("prompt", "") or "").strip()
             data.pop("greeting", None)
@@ -390,6 +439,16 @@ def validate_graph(graph: dict[str, Any]) -> list[str]:
             entry_mode = data.get("entryMode", "wait_user")
             if entry_mode not in AGENT_ENTRY_MODES:
                 errors.append(f"Agent 节点 {node_id} 的进入模式无效:{entry_mode}")
+            system_tools = data.get("systemTools", [])
+            if not isinstance(system_tools, list) or any(
+                tool not in SYSTEM_TOOL_KINDS for tool in system_tools
+            ):
+                errors.append(f"Agent 节点 {node_id} 的系统工具配置无效")
+            state_names = data.get("stateVariableNames", [])
+            if not isinstance(state_names, list) or any(
+                not isinstance(name, str) for name in state_names
+            ):
+                errors.append(f"Agent 节点 {node_id} 的状态变量授权必须是列表")
         elif node_type == "message":
             data = node.get("data") or {}
             speech = data.get("speech")
@@ -447,6 +506,13 @@ def validate_graph(graph: dict[str, Any]) -> list[str]:
                 errors.append(
                     f"Action 节点 {node_id} 的用户输入策略无效:{input_policy}"
                 )
+        elif node_type == "update_state":
+            data = node.get("data") or {}
+            assignments = data.get("assignments")
+            if not isinstance(assignments, dict) or not assignments:
+                errors.append(
+                    f"Update State 节点 {node_id} 必须配置至少一个变量赋值"
+                )
 
     if counts["start"] != 1:
         errors.append("工作流必须有且仅有一个 Start 节点")

backend/services/system_tools.py

@@ -0,0 +1,54 @@
+"""Shared contracts for platform-owned conversation system tools."""
+
+from __future__ import annotations
+
+from collections.abc import Iterable, Mapping
+from typing import Any
+
+
+SYSTEM_TOOL_KINDS = frozenset(
+    {
+        "end_conversation",
+        "update_state",
+        "skip_turn",
+        "request_human_handoff",
+    }
+)
+
+
+def normalize_system_tools(values: Iterable[Any] | None) -> tuple[str, ...]:
+    """Return known tool names once each while preserving editor order."""
+    return tuple(
+        dict.fromkeys(
+            str(value)
+            for value in values or ()
+            if str(value) in SYSTEM_TOOL_KINDS
+        )
+    )
+
+
+def state_update_properties(
+    definitions: Mapping[str, Mapping[str, Any]] | None,
+    *,
+    allowed_names: Iterable[str] | None = None,
+) -> dict[str, dict[str, Any]]:
+    """Build an explicit LLM schema for writable declared variables."""
+    definitions = definitions or {}
+    names = (
+        list(dict.fromkeys(str(name) for name in allowed_names))
+        if allowed_names is not None
+        else list(definitions)
+    )
+    properties: dict[str, dict[str, Any]] = {}
+    for name in names:
+        definition = definitions.get(name)
+        if not isinstance(definition, Mapping):
+            continue
+        variable_type = str(definition.get("type") or "string")
+        if variable_type not in {"string", "number", "boolean"}:
+            continue
+        properties[name] = {
+            "type": variable_type,
+            "description": f"更新动态变量 {name}。",
+        }
+    return properties

backend/services/workflow_engine.py

@@ -11,6 +11,7 @@ from typing import Any
 
 from services.node_specs import normalize_graph
 from services.runtime_variables import DynamicVariableStore
+from services.system_tools import normalize_system_tools
 
 
 @dataclass(frozen=True)
@@ -24,6 +25,8 @@ class AgentStageConfig:
     vision_enabled: bool
     vision_model_resource_id: str | None
     tool_ids: tuple[str, ...]
+    system_tools: tuple[str, ...]
+    state_variable_names: tuple[str, ...]
     knowledge_base_id: str | None
     knowledge_mode: str
     knowledge_top_n: int
@@ -145,6 +148,16 @@ class WorkflowEngine:
                 str(source.get("visionModelResourceId") or "") or None
             ),
             tool_ids=tuple(str(tool_id) for tool_id in source.get("toolIds") or []),
+            # System tools and their writable state scope always belong to the
+            # Agent node. They are permissions, not inheritable model config.
+            system_tools=normalize_system_tools(data.get("systemTools")),
+            state_variable_names=tuple(
+                dict.fromkeys(
+                    str(name)
+                    for name in data.get("stateVariableNames") or []
+                    if str(name)
+                )
+            ),
             knowledge_base_id=knowledge_base_id or None,
             knowledge_mode=(
                 str(source.get("knowledgeMode") or "automatic")

backend/tests/test_brains.py

@@ -154,6 +154,46 @@ class BrainRegistryTests(unittest.TestCase):
         )
         self.assertIn("user_name", assistant.dynamic_variable_definitions)
 
+    def test_system_tools_are_prompt_pipeline_only(self):
+        assistant = AssistantUpsert(
+            name="prompt",
+            type="prompt",
+            systemTools=["end_conversation", "skip_turn", "end_conversation"],
+        )
+        self.assertEqual(assistant.system_tools, ["end_conversation", "skip_turn"])
+
+        workflow = AssistantUpsert(
+            name="workflow",
+            type="workflow",
+            systemTools=["update_state"],
+            graph={},
+        )
+        self.assertEqual(workflow.system_tools, [])
+
+        with self.assertRaises(ValueError):
+            AssistantUpsert(
+                name="realtime prompt",
+                type="prompt",
+                runtimeMode="realtime",
+                systemTools=["skip_turn"],
+            )
+
+    def test_system_tools_reject_unknown_kind(self):
+        with self.assertRaises(ValueError):
+            AssistantUpsert(
+                name="prompt",
+                type="prompt",
+                systemTools=["update_state", "magic"],
+            )
+
+    def test_prompt_update_state_requires_a_declared_variable(self):
+        with self.assertRaisesRegex(ValueError, "必须声明至少一个动态变量"):
+            AssistantUpsert(
+                name="prompt",
+                type="prompt",
+                systemTools=["update_state"],
+            )
+
     def test_workflow_keeps_dynamic_variables_and_tool_bindings(self):
         assistant = AssistantUpsert(
             name="workflow",
@@ -757,7 +797,7 @@ class PromptBrainTests(unittest.IsolatedAsyncioTestCase):
         self.assertEqual(prompts, ["面板状态：true"])
         self.assertEqual(queued_frames, [])
 
-    async def test_end_call_tool_is_owned_by_prompt_brain(self):
+    async def test_end_conversation_system_tool_is_owned_by_prompt_brain(self):
         brain = build_brain(
             AssistantConfig(
                 type="prompt",
@@ -766,9 +806,10 @@ class PromptBrainTests(unittest.IsolatedAsyncioTestCase):
                         id="end-call",
                         name="结束通话",
                         function_name="end_call",
-                        type="end_call",
+                        type="system",
                         definition={
                             "config": {
+                                "kind": "end_conversation",
                                 "message_type": "none",
                                 "capture_reason": True,
                             }
@@ -792,8 +833,13 @@ class PromptBrainTests(unittest.IsolatedAsyncioTestCase):
                         id="end-call",
                         name="结束通话",
                         function_name="end_call",
-                        type="end_call",
-                        definition={"config": {"capture_reason": True}},
+                        type="system",
+                        definition={
+                            "config": {
+                                "kind": "end_conversation",
+                                "capture_reason": True,
+                            }
+                        },
                     )
                 ],
             ),
@@ -819,13 +865,18 @@ class PromptBrainTests(unittest.IsolatedAsyncioTestCase):
         self.assertTrue(call_end.response_started)
         self.assertEqual(params.result["action"], "ending_call")
 
-    async def test_end_call_waits_for_prompt_generated_closing_speech(self):
+    async def test_system_end_conversation_waits_for_generated_closing_speech(self):
         tool = RuntimeTool(
             id="end-call",
             name="结束通话",
             function_name="end_call",
-            type="end_call",
-            definition={"config": {"message_type": "none"}},
+            type="system",
+            definition={
+                "config": {
+                    "kind": "end_conversation",
+                    "message_type": "none",
+                }
+            },
         )
         cfg = AssistantConfig(type="prompt", tools=[tool])
         brain = build_brain(cfg)
@@ -855,6 +906,279 @@ class PromptBrainTests(unittest.IsolatedAsyncioTestCase):
         self.assertTrue(call_end.armed)
         self.assertTrue(call_end.waited_for_text)
 
+    async def test_system_tools_register_with_fixed_names(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            dynamic_variable_definitions={
+                "user_name": {
+                    "type": "string",
+                    "required": False,
+                    "default": None,
+                }
+            },
+            system_tools=[
+                "end_conversation",
+                "update_state",
+                "skip_turn",
+                "request_human_handoff",
+            ],
+        )
+        brain = build_brain(cfg)
+        llm = FakeLLM()
+        visible_tools = []
+
+        await brain.setup(
+            cfg,
+            BrainRuntime(
+                context=LLMContext(messages=[]),
+                llm=llm,
+                queue_frame=lambda _frame: None,
+                set_system_prompt=lambda _prompt: None,
+                set_tools=lambda tools: visible_tools.extend(tools or []),
+                call_end=FakeCallEnd(),
+            ),
+        )
+
+        self.assertEqual(
+            [tool.name for tool in visible_tools],
+            [
+                "end_conversation",
+                "update_state",
+                "skip_turn",
+                "request_human_handoff",
+            ],
+        )
+        update_schema = next(
+            tool for tool in visible_tools if tool.name == "update_state"
+        )
+        self.assertEqual(
+            update_schema.properties,
+            {
+                "user_name": {
+                    "type": "string",
+                    "description": "更新动态变量 user_name。",
+                }
+            },
+        )
+        for name in (
+            "end_conversation",
+            "update_state",
+            "skip_turn",
+            "request_human_handoff",
+        ):
+            self.assertIn(name, llm.functions)
+
+    async def test_end_conversation_ends_call_after_generated_speech(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            system_tools=["end_conversation"],
+        )
+        brain = build_brain(cfg)
+        llm = FakeLLM()
+        call_end = FakeCallEnd()
+
+        await brain.setup(
+            cfg,
+            BrainRuntime(
+                context=LLMContext(messages=[]),
+                llm=llm,
+                queue_frame=lambda _frame: None,
+                set_system_prompt=lambda _prompt: None,
+                set_tools=lambda _tools: None,
+                call_end=call_end,
+            ),
+        )
+
+        await brain.on_assistant_text_start("turn-1")
+        params = FakeFunctionParams({"reason": "用户已完成咨询"})
+        await llm.functions["end_conversation"](params)
+        self.assertEqual(call_end.reason, "用户已完成咨询")
+        self.assertTrue(call_end.ending)
+        self.assertFalse(call_end.finished)
+        self.assertEqual(params.result["action"], "ending_call")
+        self.assertFalse(params.properties.run_llm)
+
+        await brain.on_assistant_text_end(
+            "turn-1",
+            "好的，再见。",
+            False,
+        )
+        self.assertFalse(call_end.finished)
+        self.assertTrue(call_end.armed)
+
+    async def test_end_conversation_finishes_when_no_speech(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            system_tools=["end_conversation"],
+        )
+        brain = build_brain(cfg)
+        llm = FakeLLM()
+        call_end = FakeCallEnd()
+
+        await brain.setup(
+            cfg,
+            BrainRuntime(
+                context=LLMContext(messages=[]),
+                llm=llm,
+                queue_frame=lambda _frame: None,
+                set_system_prompt=lambda _prompt: None,
+                set_tools=lambda _tools: None,
+                call_end=call_end,
+            ),
+        )
+
+        await brain.on_assistant_text_start("turn-1")
+        await llm.functions["end_conversation"](FakeFunctionParams({}))
+        await brain.on_assistant_text_end("turn-1", "", False)
+        self.assertTrue(call_end.finished)
+
+    async def test_update_state_updates_declared_variables(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            prompt="当前用户名: {{user_name}}",
+            dynamic_variable_definitions={
+                "user_name": {"type": "string", "required": False, "default": None}
+            },
+            system_tools=["update_state"],
+        )
+        brain = build_brain(cfg)
+        llm = FakeLLM()
+        prompts = []
+        queued_frames = []
+
+        async def collect(frame):
+            queued_frames.append(frame)
+
+        await brain.setup(
+            cfg,
+            BrainRuntime(
+                context=LLMContext(messages=[]),
+                llm=llm,
+                queue_frame=collect,
+                set_system_prompt=prompts.append,
+                set_tools=lambda _tools: None,
+                call_end=FakeCallEnd(),
+            ),
+        )
+
+        params = FakeFunctionParams({"user_name": "王小明"})
+        await llm.functions["update_state"](params)
+
+        self.assertEqual(params.result["status"], "success")
+        self.assertEqual(params.result["changed"], ["user_name"])
+        self.assertIsNone(params.properties)
+        self.assertEqual(
+            [frame.message for frame in queued_frames],
+            [
+                {
+                    "type": "session-variables",
+                    "reason": "update_state",
+                    "variables": {"user_name": "王小明"},
+                    "changed": ["user_name"],
+                }
+            ],
+        )
+        self.assertTrue(prompts[-1].endswith("当前用户名: 王小明"))
+
+    async def test_update_state_rejects_undeclared_variable(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            system_tools=["update_state"],
+        )
+        brain = build_brain(cfg)
+        llm = FakeLLM()
+
+        await brain.setup(
+            cfg,
+            BrainRuntime(
+                context=LLMContext(messages=[]),
+                llm=llm,
+                queue_frame=lambda _frame: None,
+                set_system_prompt=lambda _prompt: None,
+                set_tools=lambda _tools: None,
+                call_end=FakeCallEnd(),
+            ),
+        )
+
+        params = FakeFunctionParams({"unknown_key": "x"})
+        await llm.functions["update_state"](params)
+        self.assertEqual(params.result["status"], "error")
+        self.assertIn("未声明", params.result["message"])
+
+    async def test_skip_turn_suppresses_response(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            system_tools=["skip_turn"],
+        )
+        brain = build_brain(cfg)
+        llm = FakeLLM()
+
+        await brain.setup(
+            cfg,
+            BrainRuntime(
+                context=LLMContext(messages=[]),
+                llm=llm,
+                queue_frame=lambda _frame: None,
+                set_system_prompt=lambda _prompt: None,
+                set_tools=lambda _tools: None,
+                call_end=FakeCallEnd(),
+            ),
+        )
+
+        params = FakeFunctionParams({"reason": "无需回复"})
+        await llm.functions["skip_turn"](params)
+        self.assertEqual(params.result["action"], "skip_turn")
+        self.assertEqual(params.result["reason"], "无需回复")
+        self.assertFalse(params.properties.run_llm)
+
+    async def test_request_human_handoff_keeps_call_available(self):
+        cfg = AssistantConfig(
+            type="prompt",
+            system_tools=["request_human_handoff"],
+        )
+        brain = build_brain(cfg)
+        llm = FakeLLM()
+        call_end = FakeCallEnd()
+        queued_frames = []
+
+        async def collect(frame):
+            queued_frames.append(frame)
+
+        await brain.setup(
+            cfg,
+            BrainRuntime(
+                context=LLMContext(messages=[]),
+                llm=llm,
+                queue_frame=collect,
+                set_system_prompt=lambda _prompt: None,
+                set_tools=lambda _tools: None,
+                call_end=call_end,
+            ),
+        )
+
+        await brain.on_assistant_text_start("turn-1")
+        params = FakeFunctionParams({"reason": "用户要求人工客服"})
+        await llm.functions["request_human_handoff"](params)
+
+        self.assertEqual(
+            [frame.message for frame in queued_frames],
+            [
+                {
+                    "type": "handoff-requested",
+                    "source": "prompt-system-tool",
+                    "reason": "用户要求人工客服",
+                    "message": "用户请求转接人工服务。",
+                }
+            ],
+        )
+        self.assertEqual(call_end.reason, "")
+        self.assertFalse(call_end.ending)
+        self.assertEqual(params.result["action"], "human_handoff_requested")
+        self.assertIsNone(params.properties)
+
+        await brain.on_assistant_text_end("turn-1", "", False)
+        self.assertFalse(call_end.finished)
+
     async def test_http_tool_renders_secrets_and_updates_prompt_variable(self):
         requests = []
 
@@ -962,6 +1286,195 @@ class PromptBrainTests(unittest.IsolatedAsyncioTestCase):
 
 
 class WorkflowBrainTests(unittest.IsolatedAsyncioTestCase):
+    async def test_agent_system_tools_are_scoped_and_update_declared_state(self):
+        cfg = prepare_dynamic_config(
+            AssistantConfig(
+                type="workflow",
+                graph={
+                    "specVersion": 3,
+                    "settings": {},
+                    "nodes": [
+                        {"id": "start", "type": "start", "data": {}},
+                        {
+                            "id": "agent",
+                            "type": "agent",
+                            "data": {
+                                "systemTools": [
+                                    "update_state",
+                                    "skip_turn",
+                                    "request_human_handoff",
+                                ],
+                                "stateVariableNames": ["customer_name"],
+                            },
+                        },
+                    ],
+                    "edges": [],
+                },
+                dynamic_variable_definitions={
+                    "customer_name": {
+                        "type": "string",
+                        "required": False,
+                        "default": None,
+                    },
+                    "internal_note": {
+                        "type": "string",
+                        "required": False,
+                        "default": None,
+                    },
+                },
+            ),
+            {},
+            assistant_id="asst_workflow_system_tools",
+        )
+        brain = WorkflowBrain(cfg)
+        queued = []
+
+        async def queue_frame(frame):
+            queued.append(frame)
+
+        brain._runtime = BrainRuntime(
+            context=LLMContext(messages=[]),
+            llm=FakeLLM(),
+            queue_frame=queue_frame,
+            set_system_prompt=lambda _prompt: None,
+            set_tools=lambda _tools: None,
+            call_end=FakeCallEnd(),
+        )
+        brain._agent_stage = SimpleNamespace(
+            node_config=lambda node_id, *, functions, leading_messages: {
+                "name": node_id,
+                "functions": functions,
+                "leading_messages": leading_messages,
+            }
+        )
+        brain._emit_variables = AsyncMock()
+        brain._refresh_agent_prompt = AsyncMock()
+
+        node_config = brain._agent_config("agent")
+        functions = {tool.name: tool for tool in node_config["functions"]}
+        self.assertEqual(
+            list(functions),
+            ["update_state", "skip_turn", "request_human_handoff"],
+        )
+        self.assertEqual(
+            list(functions["update_state"].properties),
+            ["customer_name"],
+        )
+
+        result = await functions["update_state"].handler(
+            {"customer_name": "李白"},
+            None,
+        )
+        self.assertEqual(result["changed"], ["customer_name"])
+        self.assertEqual(brain._store.public_values(), {"customer_name": "李白"})
+        brain._emit_variables.assert_awaited_once_with(
+            reason="update_state",
+            node_id="agent",
+            changed=["customer_name"],
+        )
+        brain._refresh_agent_prompt.assert_awaited_once_with("agent")
+
+        unauthorized = await functions["update_state"].handler(
+            {"internal_note": "不可写"},
+            None,
+        )
+        self.assertEqual(unauthorized["status"], "error")
+        self.assertIn("未获当前节点授权", unauthorized["message"])
+
+        handoff = await functions["request_human_handoff"].handler(
+            {"reason": "用户要求人工"},
+            None,
+        )
+        self.assertEqual(handoff["status"], "requested")
+        self.assertFalse(brain._runtime.call_end.ending)
+        event = next(
+            frame.message
+            for frame in queued
+            if isinstance(frame, OutputTransportMessageUrgentFrame)
+        )
+        self.assertEqual(event["type"], "handoff-requested")
+        self.assertEqual(event["source"], "workflow-system-tool")
+
+    async def test_update_state_node_applies_assignments_atomically(self):
+        cfg = prepare_dynamic_config(
+            AssistantConfig(
+                type="workflow",
+                graph={
+                    "specVersion": 3,
+                    "settings": {},
+                    "nodes": [
+                        {"id": "start", "type": "start", "data": {}},
+                        {
+                            "id": "set_state",
+                            "type": "update_state",
+                            "data": {
+                                "assignments": {
+                                    "confirmed": True,
+                                    "display_name": "{{source_name}}",
+                                }
+                            },
+                        },
+                    ],
+                    "edges": [],
+                },
+                dynamic_variable_definitions={
+                    "source_name": {"type": "string", "default": "李白"},
+                    "display_name": {
+                        "type": "string",
+                        "required": False,
+                        "default": None,
+                    },
+                    "confirmed": {"type": "boolean", "default": False},
+                },
+            ),
+            {},
+            assistant_id="asst_workflow_update_state_node",
+        )
+        brain = WorkflowBrain(cfg)
+        brain._emit_node_active = AsyncMock()
+        brain._emit_variables = AsyncMock()
+
+        await brain._enter_update_state("set_state")
+
+        self.assertEqual(brain._store.public_values()["display_name"], "李白")
+        self.assertTrue(brain._store.public_values()["confirmed"])
+        brain._emit_variables.assert_awaited_once_with(
+            reason="update_state",
+            node_id="set_state",
+            changed=["confirmed", "display_name"],
+        )
+
+    async def test_workflow_end_conversation_waits_for_generated_speech(self):
+        brain = WorkflowBrain(
+            {
+                "specVersion": 3,
+                "settings": {},
+                "nodes": [{"id": "start", "type": "start", "data": {}}],
+                "edges": [],
+            }
+        )
+        call_end = FakeCallEnd()
+        brain._runtime = BrainRuntime(
+            context=LLMContext(messages=[]),
+            llm=FakeLLM(),
+            queue_frame=noop_queue_frame,
+            set_system_prompt=lambda _prompt: None,
+            set_tools=lambda _tools: None,
+            call_end=call_end,
+        )
+        tool = brain._workflow_end_conversation_tool()
+
+        await brain.on_assistant_text_start("turn-1")
+        result = await tool.handler({"reason": "用户告别"}, None)
+        self.assertEqual(result["action"], "ending_call")
+        self.assertTrue(call_end.ending)
+        self.assertEqual(call_end.reason, "用户告别")
+        self.assertTrue(getattr(tool.handler, "_suppress_followup_llm"))
+
+        await brain.on_assistant_text_end("turn-1", "再见。", False)
+        self.assertTrue(call_end.armed)
+        self.assertTrue(call_end.waited_for_text)
+
     async def test_flow_manager_dispatches_native_vision_without_auxiliary_handler(self):
         manager = object.__new__(ConfiguredFlowManager)
         fallback_transition = AsyncMock()

backend/tests/test_workflow_v3.py

@@ -360,6 +360,13 @@ class WorkflowGraphTests(unittest.TestCase):
 
     def test_agent_effective_config_inherits_then_switches_to_override(self):
         graph = valid_graph()
+        agent = next(node for node in graph["nodes"] if node["id"] == "agent")
+        agent["data"].update(
+            {
+                "systemTools": ["update_state", "skip_turn"],
+                "stateVariableNames": ["customer", "order_status"],
+            }
+        )
         graph["settings"].update(
             {
                 "defaultLlmResourceId": "llm_global",
@@ -389,6 +396,11 @@ class WorkflowGraphTests(unittest.TestCase):
         )
         self.assertTrue(engine.uses_vision())
         self.assertEqual(inherited.tool_ids, ("tool_global",))
+        self.assertEqual(inherited.system_tools, ("update_state", "skip_turn"))
+        self.assertEqual(
+            inherited.state_variable_names,
+            ("customer", "order_status"),
+        )
         self.assertEqual(inherited.knowledge_mode, "on_demand")
         self.assertFalse(inherited.enable_interrupt)
         self.assertEqual(
@@ -417,6 +429,7 @@ class WorkflowGraphTests(unittest.TestCase):
         self.assertIsNone(custom.vision_model_resource_id)
         self.assertFalse(engine.uses_vision())
         self.assertEqual(custom.tool_ids, ("tool_agent",))
+        self.assertEqual(custom.system_tools, ("update_state", "skip_turn"))
         self.assertEqual(custom.knowledge_mode, "disabled")
         self.assertTrue(custom.enable_interrupt)
         self.assertEqual(
@@ -424,6 +437,84 @@ class WorkflowGraphTests(unittest.TestCase):
             "smart_turn",
         )
 
+    def test_update_state_node_and_agent_state_scope_are_validated(self):
+        graph = valid_graph()
+        graph["nodes"].insert(
+            1,
+            {
+                "id": "set_state",
+                "type": "update_state",
+                "data": {
+                    "name": "记录状态",
+                    "assignments": {"confirmed": True},
+                },
+            },
+        )
+        graph["edges"][0]["target"] = "set_state"
+        graph["edges"].insert(
+            1,
+            {
+                "id": "after_state",
+                "source": "set_state",
+                "target": "agent",
+                "data": {"mode": "always", "priority": 0},
+            },
+        )
+        agent = next(node for node in graph["nodes"] if node["id"] == "agent")
+        agent["data"].update(
+            {
+                "systemTools": ["update_state"],
+                "stateVariableNames": ["customer"],
+            }
+        )
+        body = AssistantUpsert(
+            name="状态工作流",
+            type="workflow",
+            dynamicVariableDefinitions={
+                "confirmed": {
+                    "type": "boolean",
+                    "required": False,
+                    "default": False,
+                },
+                "customer": {
+                    "type": "string",
+                    "required": False,
+                    "default": None,
+                },
+            },
+            graph=graph,
+        )
+
+        _validate_workflow(body)
+        normalized_state = next(
+            node for node in body.graph["nodes"] if node["type"] == "update_state"
+        )
+        self.assertEqual(normalized_state["data"]["assignments"], {"confirmed": True})
+
+        normalized_state["data"]["assignments"] = {"missing": "x"}
+        with self.assertRaisesRegex(HTTPException, "未声明变量:missing"):
+            _validate_workflow(body)
+
+    def test_agent_update_state_tool_requires_an_authorized_variable(self):
+        graph = valid_graph()
+        agent = next(node for node in graph["nodes"] if node["id"] == "agent")
+        agent["data"]["systemTools"] = ["update_state"]
+        body = AssistantUpsert(
+            name="缺少授权",
+            type="workflow",
+            dynamicVariableDefinitions={
+                "customer": {
+                    "type": "string",
+                    "required": False,
+                    "default": None,
+                }
+            },
+            graph=graph,
+        )
+
+        with self.assertRaisesRegex(HTTPException, "必须授权至少一个变量"):
+            _validate_workflow(body)
+
     def test_vision_resource_creates_isolated_runtime_config(self):
         base = AssistantConfig(type="workflow", model="text-only")
         resource = RuntimeModelResource(

docs/features.mdx

@@ -26,6 +26,7 @@ icon: bot
 
 ## 工具与历史
 
-- 可复用工具支持结束通话和 HTTP 请求两种类型。
+- 可复用工具分为 System、HTTP、Client 和 MCP；结束对话属于 System 类别。
 - HTTP 工具的 URL、请求头、参数和密钥独立管理。
+- Prompt 助手和 Workflow Agent 节点可开启内置系统工具：结束对话、更新状态、跳过本轮、请求人工接管；Workflow 还提供确定性的 Update State 节点。
 - 历史记录保留会话、通道、运行模式及消息序列，便于排查对话。

frontend/src/components/assistant-editor/dynamic-variables.tsx

@@ -3,7 +3,6 @@
 import { Check, Copy } from "lucide-react";
 import { useState } from "react";
 
-import { Badge } from "@/components/ui/badge";
 import { Input } from "@/components/ui/input";
 import {
   Select,
@@ -252,12 +251,18 @@ function DynamicVariablesEditor({
                       <code className="truncate font-mono text-sm font-medium text-foreground">
                         {`{{${name}}}`}
                       </code>
-                      <Badge
-                        variant="secondary"
-                        className="shrink-0 rounded-full px-2 py-0.5 text-[10px] font-medium"
-                      >
-                        已引用
-                      </Badge>
+                      <div className="flex shrink-0 items-center gap-2">
+                        <span className="text-xs text-muted-foreground">
+                          会话开始时必须提供
+                        </span>
+                        <Switch
+                          checked={definition.required}
+                          aria-label={`变量 ${name} 必填`}
+                          onCheckedChange={(required) =>
+                            updateDefinition(name, { required })
+                          }
+                        />
+                      </div>
                     </div>
                     <div className="grid grid-cols-[120px_1fr] gap-2">
                       <Select
@@ -328,18 +333,6 @@ function DynamicVariablesEditor({
                         />
                       )}
                     </div>
-                    <div className="flex items-center justify-between gap-3">
-                      <span className="text-xs text-muted-foreground">
-                        会话开始时必须提供
-                      </span>
-                      <Switch
-                        checked={definition.required}
-                        aria-label={`变量 ${name} 必填`}
-                        onCheckedChange={(required) =>
-                          updateDefinition(name, { required })
-                        }
-                      />
-                    </div>
                   </div>
                 ))}
               </div>

frontend/src/components/assistant-editor/editor-controls.tsx

@@ -12,6 +12,7 @@ import {
   Plus,
   ServerCog,
   Settings2,
+  Sparkles,
   Waypoints,
   Wrench,
   X,
@@ -37,8 +38,19 @@ import {
   SelectValue,
 } from "@/components/ui/select";
 import { Switch } from "@/components/ui/switch";
+import {
+  Tabs,
+  TabsContent,
+  TabsList,
+  TabsTrigger,
+} from "@/components/ui/tabs";
 import { Textarea } from "@/components/ui/textarea";
-import type { KnowledgeRetrievalConfig, Tool } from "@/lib/api";
+import type {
+  KnowledgeRetrievalConfig,
+  SystemToolKind,
+  Tool,
+} from "@/lib/api";
+import { SYSTEM_TOOL_OPTIONS } from "@/lib/system-tools";
 
 import type { RuntimeMode } from "./types";
 
@@ -475,31 +487,90 @@ export function ToolPicker({
   tools,
   selectedIds,
   onChange,
+  selectedSystemTools,
+  onSystemToolsChange,
+  showBuiltInSystemTools,
 }: {
   tools: Tool[];
   selectedIds: string[];
   onChange: (ids: string[]) => void;
+  selectedSystemTools: SystemToolKind[];
+  onSystemToolsChange: (tools: SystemToolKind[]) => void;
+  showBuiltInSystemTools: boolean;
 }) {
   const [open, setOpen] = useState(false);
+  const [activeTab, setActiveTab] = useState<Tool["type"]>("system");
   const [draftIds, setDraftIds] = useState<string[]>(selectedIds);
+  const [draftSystemTools, setDraftSystemTools] =
+    useState<SystemToolKind[]>(selectedSystemTools);
   const selectedTools = selectedIds
     .map((id) => tools.find((tool) => tool.id === id))
     .filter((tool): tool is Tool => Boolean(tool));
+  const selectedBuiltInTools = selectedSystemTools
+    .map((kind) => SYSTEM_TOOL_OPTIONS.find((option) => option.value === kind))
+    .filter((option): option is (typeof SYSTEM_TOOL_OPTIONS)[number] =>
+      Boolean(option),
+    );
 
   function openPicker() {
     setDraftIds(selectedIds);
+    setDraftSystemTools(selectedSystemTools);
     setOpen(true);
   }
 
+  function toggleResourceTool(toolId: string) {
+    setDraftIds((current) =>
+      current.includes(toolId)
+        ? current.filter((id) => id !== toolId)
+        : [...current, toolId],
+    );
+  }
+
+  function toggleBuiltInTool(kind: SystemToolKind) {
+    setDraftSystemTools((current) =>
+      current.includes(kind)
+        ? current.filter((item) => item !== kind)
+        : [...current, kind],
+    );
+  }
+
+  const tabs: Array<{ value: Tool["type"]; label: string }> = [
+    { value: "system", label: "System" },
+    { value: "http", label: "HTTP" },
+    { value: "client", label: "Client" },
+    { value: "mcp", label: "MCP" },
+  ];
+
   return (
     <>
       <div className="flex min-h-9 flex-wrap items-center gap-2">
+        {selectedBuiltInTools.map((tool) => (
+          <div
+            key={`built-in-${tool.value}`}
+            className="flex h-8 items-center gap-2 rounded-lg border border-hairline-strong bg-background px-2.5 text-sm"
+          >
+            <Sparkles size={14} />
+            <span className="max-w-48 truncate">{tool.label}</span>
+            <button
+              type="button"
+              onClick={() =>
+                onSystemToolsChange(
+                  selectedSystemTools.filter((kind) => kind !== tool.value),
+                )
+              }
+              className="text-muted-soft transition-colors hover:text-foreground"
+              aria-label={`移除系统工具 ${tool.label}`}
+            >
+              <X size={13} />
+            </button>
+          </div>
+        ))}
         {selectedTools.map((tool) => (
           <div
             key={tool.id}
             className="flex h-8 items-center gap-2 rounded-lg border border-hairline-strong bg-background px-2.5 text-sm"
           >
-            {tool.type === "end_call" ? (
+            {tool.type === "system" ? (
               <PhoneOff size={14} />
             ) : tool.type === "mcp" ? (
               <ServerCog size={14} />
@@ -534,58 +605,108 @@ export function ToolPicker({
         <DialogContent className="sm:max-w-xl">
           <DialogHeader>
             <DialogTitle>选择工具</DialogTitle>
-            <DialogDescription>选择已经在工具资源中启用的工具。</DialogDescription>
+            <DialogDescription>
+              按类型选择内置系统工具或已经启用的工具资源。
+            </DialogDescription>
           </DialogHeader>
 
-          {tools.length === 0 ? (
-            <div className="rounded-xl border border-dashed border-hairline-strong px-4 py-10 text-center text-sm text-muted-foreground">
-              暂无可用工具
-            </div>
-          ) : (
-            <div className="max-h-80 divide-y divide-hairline overflow-y-auto rounded-xl border border-hairline">
-              {tools.map((tool) => {
-                const checked = draftIds.includes(tool.id);
-                return (
-                  <label
-                    key={tool.id}
-                    className="flex cursor-pointer items-center gap-3 px-4 py-3 transition-colors hover:bg-surface-strong/40"
-                  >
-                    <input
-                      type="checkbox"
-                      checked={checked}
-                      onChange={() =>
-                        setDraftIds((current) =>
-                          checked
-                            ? current.filter((id) => id !== tool.id)
-                            : [...current, tool.id],
-                        )
-                      }
-                      className="size-4 accent-primary"
-                    />
-                    <div className="min-w-0 flex-1">
-                      <div className="flex items-center gap-2">
-                        <span className="truncate font-medium text-foreground">
-                          {tool.name}
-                        </span>
-                        <Badge variant="secondary">
-                          {tool.type === "end_call"
-                            ? "End Call"
-                            : tool.type === "mcp"
-                              ? "MCP"
-                              : tool.type === "client"
-                                ? "Client"
-                                : "HTTP"}
-                        </Badge>
-                      </div>
-                      <div className="mt-0.5 truncate font-mono text-xs text-muted-foreground">
-                        {tool.functionName}
-                      </div>
+          <Tabs
+            value={activeTab}
+            onValueChange={(value) => setActiveTab(value as Tool["type"])}
+          >
+            <TabsList
+              variant="line"
+              className="w-full justify-start border-b border-hairline px-1"
+            >
+              {tabs.map((tab) => (
+                <TabsTrigger
+                  key={tab.value}
+                  value={tab.value}
+                  className="flex-none px-4"
+                >
+                  {tab.label}
+                </TabsTrigger>
+              ))}
+            </TabsList>
+
+            {tabs.map((tab) => {
+              const resources = tools.filter((tool) => tool.type === tab.value);
+              const hasBuiltIns =
+                tab.value === "system" && showBuiltInSystemTools;
+              const isEmpty = resources.length === 0 && !hasBuiltIns;
+
+              return (
+                <TabsContent key={tab.value} value={tab.value} className="pt-3">
+                  {isEmpty ? (
+                    <div className="rounded-xl border border-dashed border-hairline-strong px-4 py-10 text-center text-sm text-muted-foreground">
+                      暂无可用的 {tab.label} 工具
                     </div>
-                  </label>
-                );
-              })}
-            </div>
-          )}
+                  ) : (
+                    <div className="max-h-[280px] divide-y divide-hairline overflow-y-auto rounded-xl border border-hairline">
+                      {hasBuiltIns &&
+                        SYSTEM_TOOL_OPTIONS.map((option) => {
+                          const checked = draftSystemTools.includes(option.value);
+                          return (
+                            <label
+                              key={`built-in-${option.value}`}
+                              className="flex h-14 cursor-pointer items-center gap-3 px-4 transition-colors hover:bg-surface-strong/40"
+                            >
+                              <input
+                                type="checkbox"
+                                checked={checked}
+                                onChange={() => toggleBuiltInTool(option.value)}
+                                className="size-4 accent-primary"
+                              />
+                              <div className="min-w-0 flex-1">
+                                <div className="flex items-center gap-2">
+                                  <span className="truncate font-medium text-foreground">
+                                    {option.label}
+                                  </span>
+                                  <Badge variant="secondary">内置</Badge>
+                                </div>
+                                <div className="mt-0.5 truncate text-xs text-muted-foreground">
+                                  {option.description}
+                                </div>
+                              </div>
+                            </label>
+                          );
+                        })}
+
+                      {resources.map((tool) => {
+                        const checked = draftIds.includes(tool.id);
+                        return (
+                          <label
+                            key={tool.id}
+                            className="flex h-14 cursor-pointer items-center gap-3 px-4 transition-colors hover:bg-surface-strong/40"
+                          >
+                            <input
+                              type="checkbox"
+                              checked={checked}
+                              onChange={() => toggleResourceTool(tool.id)}
+                              className="size-4 accent-primary"
+                            />
+                            <div className="min-w-0 flex-1">
+                              <div className="flex items-center gap-2">
+                                <span className="truncate font-medium text-foreground">
+                                  {tool.name}
+                                </span>
+                                {tool.type === "system" && (
+                                  <Badge variant="secondary">资源</Badge>
+                                )}
+                              </div>
+                              <div className="mt-0.5 truncate font-mono text-xs text-muted-foreground">
+                                {tool.functionName}
+                              </div>
+                            </div>
+                          </label>
+                        );
+                      })}
+                    </div>
+                  )}
+                </TabsContent>
+              );
+            })}
+          </Tabs>
 
           <DialogFooter>
             <Button variant="outline" onClick={() => setOpen(false)}>
@@ -594,6 +715,7 @@ export function ToolPicker({
             <Button
               onClick={() => {
                 onChange(draftIds);
+                onSystemToolsChange(draftSystemTools);
                 setOpen(false);
               }}
             >

frontend/src/components/assistant-editor/prompt-editor.tsx

@@ -506,6 +506,9 @@ export function PromptEditor({
                         openingMessage: null,
                       });
                     }
+                    if (runtimeMode === "realtime" && form.systemTools.length) {
+                      updateForm("systemTools", []);
+                    }
                   }}
                 />
 
@@ -602,6 +605,11 @@ export function PromptEditor({
                   tools={tools.filter((tool) => tool.status === "active")}
                   selectedIds={form.toolIds}
                   onChange={(toolIds) => updateForm("toolIds", toolIds)}
+                  selectedSystemTools={form.systemTools}
+                  onSystemToolsChange={(systemTools) =>
+                    updateForm("systemTools", systemTools)
+                  }
+                  showBuiltInSystemTools={form.runtimeMode === "pipeline"}
                 />
               </SectionCard>
             </section>

frontend/src/components/assistant-editor/types.ts

@@ -2,6 +2,7 @@ import type {
   DynamicVariableDefinition,
   KnowledgeRetrievalConfig,
   StartupConfig,
+  SystemToolKind,
   TurnConfig,
 } from "@/lib/api";
 
@@ -22,6 +23,7 @@ export type AssistantForm = {
   enableInterrupt: boolean;
   turnConfig: TurnConfig;
   startup: StartupConfig;
+  systemTools: SystemToolKind[];
   visionEnabled: boolean;
   visionModelResourceId: string;
   toolIds: string[];

frontend/src/components/assistant-editor/workflow-page.tsx

@@ -185,6 +185,12 @@ export function WorkflowPage({
             modelOptions={modelOptions}
             toolOptions={toolOptions}
             knowledgeOptions={kbOptions}
+            dynamicVariableOptions={Object.entries(
+              dynamicVariableDefinitions,
+            ).map(([value, definition]) => ({
+              value,
+              label: `${value} · ${definition.type}`,
+            }))}
           />
         </div>
       </div>

frontend/src/components/pages/AssistantPage.tsx

@@ -184,6 +184,7 @@ function blankPromptForm(name: string): AssistantForm {
       actions: [],
       openingMessage: null,
     },
+    systemTools: [],
     visionEnabled: false,
     visionModelResourceId: "",
     toolIds: [],
@@ -479,6 +480,7 @@ export function AssistantPage(props: AssistantPageProps) {
         actions: a.startup?.actions ?? [],
         openingMessage: a.startup?.openingMessage ?? null,
       },
+      systemTools: a.systemTools ?? [],
       visionEnabled: a.visionEnabled,
       visionModelResourceId: a.visionModelResourceId ?? "",
       toolIds: a.toolIds ?? [],
@@ -555,6 +557,7 @@ export function AssistantPage(props: AssistantPageProps) {
         actions: [],
         openingMessage: null,
       },
+      systemTools: [],
       visionEnabled: false,
       visionModelResourceId: null,
       modelResourceIds: {},
@@ -614,6 +617,7 @@ export function AssistantPage(props: AssistantPageProps) {
         enableInterrupt: form.enableInterrupt,
         turnConfig: form.turnConfig,
         startup: form.startup,
+        systemTools: form.runtimeMode === "pipeline" ? form.systemTools : [],
         visionEnabled: form.visionEnabled,
         visionModelResourceId: form.visionModelResourceId || null,
         modelResourceIds: {
@@ -1300,7 +1304,9 @@ export function AssistantPage(props: AssistantPageProps) {
           vision: visionModelOptionsFor(""),
         }}
         toolOptions={tools
-          .filter((tool) => tool.status === "active")
+          .filter(
+            (tool) => tool.status === "active" && tool.type !== "system",
+          )
           .map((tool) => ({ value: tool.id, label: tool.name }))}
         knowledgeOptions={kbOptions}
         onBack={() => router.push("/assistants")}

frontend/src/components/pages/ComponentsToolsPage.tsx

@@ -64,9 +64,9 @@ import {
   type ToolUpsert,
 } from "@/lib/api";
 
-type ToolKind = "end_call" | "http" | "client";
+type ToolKind = "system" | "http" | "client";
 type HttpMethod = HttpToolDefinition["config"]["method"];
-type ToolFilter = "全部" | "End Call" | "HTTP" | "Client" | "MCP";
+type ToolFilter = "全部" | "System" | "HTTP" | "Client" | "MCP";
 type SortOrder = "newest" | "oldest";
 type ToolResource =
   | { kind: "tool"; id: string; tool: Tool }
@@ -74,7 +74,7 @@ type ToolResource =
 
 const toolFilters: readonly ToolFilter[] = [
   "全部",
-  "End Call",
+  "System",
   "HTTP",
   "Client",
   "MCP",
@@ -112,7 +112,7 @@ function blankForm(): ToolForm {
   return {
     name: "",
     functionName: "",
-    type: "end_call",
+    type: "system",
     description: "",
     status: "active",
     messageType: "none",
@@ -147,7 +147,7 @@ function formFromTool(tool: Tool): ToolForm {
   base.type = tool.type;
   base.description = tool.description;
   base.status = tool.status;
-  if (tool.definition.type === "end_call") {
+  if (tool.definition.type === "system") {
     base.messageType = tool.definition.config.messageType;
     base.customMessage = tool.definition.config.customMessage;
     base.captureReason = tool.definition.config.captureReason;
@@ -235,7 +235,7 @@ function payloadFromForm(form: ToolForm): ToolUpsert {
     throw new Error("函数名必须以小写字母开头，且只能包含小写字母、数字和下划线");
   }
 
-  if (form.type === "end_call") {
+  if (form.type === "system") {
     return {
       name: form.name.trim(),
       functionName: form.functionName,
@@ -244,8 +244,9 @@ function payloadFromForm(form: ToolForm): ToolUpsert {
       secrets: {},
       definition: {
         schemaVersion: 1,
-        type: "end_call",
+        type: "system",
         config: {
+          kind: "end_conversation",
           messageType: form.messageType,
           customMessage: form.messageType === "custom" ? form.customMessage : "",
           captureReason: form.captureReason,
@@ -418,7 +419,7 @@ export function ComponentsToolsPage() {
       const tool = resource.tool;
       return (
         (filter === "全部" ||
-          (filter === "End Call" && tool.type === "end_call") ||
+          (filter === "System" && tool.type === "system") ||
           (filter === "HTTP" && tool.type === "http") ||
           (filter === "Client" && tool.type === "client")) &&
         (!query ||
@@ -569,8 +570,8 @@ export function ComponentsToolsPage() {
         >
           {resource.kind === "mcp"
             ? "MCP"
-            : resource.tool.type === "end_call"
-              ? "End Call"
+            : resource.tool.type === "system"
+              ? "System"
               : resource.tool.type === "client"
                 ? "Client"
                 : "HTTP"}
@@ -783,7 +784,7 @@ export function ComponentsToolsPage() {
                 >
                   <SelectTrigger className="w-full"><SelectValue /></SelectTrigger>
                   <SelectContent>
-                    <SelectItem value="end_call">End Call</SelectItem>
+                    <SelectItem value="system">System</SelectItem>
                     <SelectItem value="http">HTTP</SelectItem>
                     <SelectItem value="client">Client Tool</SelectItem>
                   </SelectContent>
@@ -826,8 +827,8 @@ export function ComponentsToolsPage() {
             </FieldSection>
 
             <FieldSection title="参数配置" scrollable tall>
-              {form.type === "end_call" ? (
-                <EndCallFields form={form} setForm={setForm} />
+              {form.type === "system" ? (
+                <SystemToolFields form={form} setForm={setForm} />
               ) : form.type === "client" ? (
                 <ClientToolFields form={form} setForm={setForm} />
               ) : (
@@ -860,7 +861,7 @@ export function ComponentsToolsPage() {
   );
 }
 
-function EndCallFields({
+function SystemToolFields({
   form,
   setForm,
 }: {
@@ -869,6 +870,16 @@ function EndCallFields({
 }) {
   return (
     <div className="space-y-4">
+      <Field label="系统动作">
+        <Select value="end_conversation" disabled>
+          <SelectTrigger className="w-full border-hairline-strong bg-background">
+            <SelectValue />
+          </SelectTrigger>
+          <SelectContent>
+            <SelectItem value="end_conversation">结束对话</SelectItem>
+          </SelectContent>
+        </Select>
+      </Field>
       <Field label="结束语">
         <Select
           value={form.messageType}

frontend/src/components/workflow/GenericNode.tsx

@@ -72,6 +72,8 @@ export function GenericNode({ id, type, data, selected }: NodeProps) {
             messagePolicy === "playback" ? "播放完继续" : null,
             messagePolicy === "confirmation" ? "确认后继续" : null,
           ].filter(Boolean)
+        : type === "update_state"
+          ? [`${Object.keys(nodeData.assignments ?? {}).length} 个变量`]
         : [];
 
   return (

frontend/src/components/workflow/WorkflowCanvas.tsx

@@ -72,6 +72,8 @@ function defaultNodeData(spec: RuntimeNodeSpec): WorkflowNodeData {
       contextPolicy: "inherit",
       inheritGlobalConfig: true,
       entryMode: "wait_user",
+      systemTools: [],
+      stateVariableNames: [],
     });
   } else if (spec.type === "action") {
     Object.assign(data, {
@@ -79,6 +81,8 @@ function defaultNodeData(spec: RuntimeNodeSpec): WorkflowNodeData {
       resultAssignmentMode: "inherit",
       userInputPolicy: "queue",
     });
+  } else if (spec.type === "update_state") {
+    Object.assign(data, { assignments: {} });
   } else if (spec.type === "message") {
     Object.assign(data, {
       speech: "",
@@ -170,6 +174,7 @@ export function WorkflowCanvas({
   specsByType,
   toolOptions = [],
   knowledgeOptions = [],
+  dynamicVariableOptions,
 }: WorkflowEditorProps & { specsByType: NodeSpecMap }) {
   const initial = useMemo(() => toFlow(value ?? defaultGraph()), [value]);
   const [nodes, setNodes, onNodesChange] = useNodesState(initial.nodes);
@@ -780,6 +785,7 @@ export function WorkflowCanvas({
                           asrOptions={modelOptions.asr}
                           ttsOptions={modelOptions.tts}
                           visionOptions={modelOptions.vision}
+                          dynamicVariableOptions={dynamicVariableOptions}
                           workflowSettings={settings}
                           onChange={(patch) =>
                             updateNodeData(editingNode.id, patch)

frontend/src/components/workflow/panels/AgentNodePanel.tsx

@@ -16,7 +16,8 @@ import { VisionConfigSection } from "@/components/editor/vision-config-section";
 import { TurnConfigEditor } from "@/components/turn-config-editor";
 import { Switch } from "@/components/ui/switch";
 import { Textarea } from "@/components/ui/textarea";
-import type { KnowledgeRetrievalConfig } from "@/lib/api";
+import type { KnowledgeRetrievalConfig, SystemToolKind } from "@/lib/api";
+import { SYSTEM_TOOL_OPTIONS } from "@/lib/system-tools";
 import { normalizeTurnConfig } from "@/lib/turn-config";
 
 import { NodeSelect, ToolOptionPicker } from "./controls";
@@ -38,6 +39,7 @@ export function AgentNodePanel({
   asrOptions,
   ttsOptions,
   visionOptions,
+  dynamicVariableOptions,
 }: {
   draft: WorkflowNodeData;
   set: (key: string, val: unknown) => void;
@@ -49,6 +51,7 @@ export function AgentNodePanel({
   asrOptions: ModelOption[];
   ttsOptions: ModelOption[];
   visionOptions: ModelOption[];
+  dynamicVariableOptions: ModelOption[];
 }) {
   const inheritsGlobal = draft.inheritGlobalConfig !== false;
   const knowledgeConfig: KnowledgeRetrievalConfig = {
@@ -101,6 +104,27 @@ export function AgentNodePanel({
       turnConfig: agentTurnConfig,
     });
   };
+  const toggleSystemTool = (kind: SystemToolKind, enabled: boolean) => {
+    const current = draft.systemTools ?? [];
+    const systemTools = enabled
+      ? [...new Set([...current, kind])]
+      : current.filter((item) => item !== kind);
+    setPatch({
+      systemTools,
+      ...(!enabled && kind === "update_state"
+        ? { stateVariableNames: [] }
+        : {}),
+    });
+  };
+  const toggleStateVariable = (name: string, enabled: boolean) => {
+    const current = draft.stateVariableNames ?? [];
+    set(
+      "stateVariableNames",
+      enabled
+        ? [...new Set([...current, name])]
+        : current.filter((item) => item !== name),
+    );
+  };
 
   return (
     <PanelAnchorNavigation
@@ -109,6 +133,7 @@ export function AgentNodePanel({
         { id: "scope", label: "配置范围" },
         { id: "prompt", label: inheritsGlobal ? "任务" : "提示词" },
         { id: "entry", label: "进入行为" },
+        { id: "system-tools", label: "系统工具" },
         ...(!inheritsGlobal
           ? [
               { id: "models", label: "模型与语音" },
@@ -186,6 +211,78 @@ export function AgentNodePanel({
         </SectionCard>
       </PanelAnchor>
 
+      <PanelAnchor id="system-tools">
+        <SectionCard
+          icon={<Sparkles size={15} />}
+          title="系统工具"
+          description="只对当前 Agent 生效的内置会话控制能力"
+        >
+          <div className="space-y-3">
+            {SYSTEM_TOOL_OPTIONS.map((option) => {
+              const enabled = (draft.systemTools ?? []).includes(option.value);
+              return (
+                <div
+                  key={option.value}
+                  className="rounded-xl border border-hairline bg-canvas-soft p-3.5"
+                >
+                  <div className="flex items-start justify-between gap-4">
+                    <div className="min-w-0">
+                      <div className="text-sm font-medium text-foreground">
+                        {option.label}
+                      </div>
+                      <p className="mt-1 text-xs leading-5 text-muted-foreground">
+                        {option.description}
+                      </p>
+                    </div>
+                    <Switch
+                      checked={enabled}
+                      onCheckedChange={(checked) =>
+                        toggleSystemTool(option.value, checked)
+                      }
+                      aria-label={`启用${option.label}`}
+                    />
+                  </div>
+                  {option.value === "update_state" && enabled && (
+                    <div className="mt-3 border-t border-hairline pt-3">
+                      <div className="mb-2 text-xs font-medium text-foreground">
+                        允许更新的变量
+                      </div>
+                      {dynamicVariableOptions.length ? (
+                        <div className="space-y-2">
+                          {dynamicVariableOptions.map((variable) => (
+                            <div
+                              key={variable.value}
+                              className="flex items-center justify-between gap-3 rounded-lg border border-hairline bg-background px-3 py-2"
+                            >
+                              <span className="truncate text-xs text-foreground">
+                                {variable.label}
+                              </span>
+                              <Switch
+                                checked={(draft.stateVariableNames ?? []).includes(
+                                  variable.value,
+                                )}
+                                onCheckedChange={(checked) =>
+                                  toggleStateVariable(variable.value, checked)
+                                }
+                                aria-label={`允许更新${variable.value}`}
+                              />
+                            </div>
+                          ))}
+                        </div>
+                      ) : (
+                        <p className="text-xs leading-5 text-muted-foreground">
+                          请先在工作流的动态变量面板中声明变量。
+                        </p>
+                      )}
+                    </div>
+                  )}
+                </div>
+              );
+            })}
+          </div>
+        </SectionCard>
+      </PanelAnchor>
+
       {!inheritsGlobal && (
         <>
           <PanelAnchor id="models">

frontend/src/components/workflow/panels/NodeSettingsPanel.tsx

@@ -12,6 +12,7 @@ import { Textarea } from "@/components/ui/textarea";
 import { ActionNodePanel } from "./ActionNodePanel";
 import { AgentNodePanel } from "./AgentNodePanel";
 import { MessageNodePanel } from "./MessageNodePanel";
+import { UpdateStateNodePanel } from "./UpdateStateNodePanel";
 import { NodeSelect, ToolOptionPicker } from "./controls";
 import {
   PanelAnchor,
@@ -31,6 +32,7 @@ export function NodeSettingsPanel({
   asrOptions,
   ttsOptions,
   visionOptions,
+  dynamicVariableOptions,
   workflowSettings,
   onChange,
 }: {
@@ -43,6 +45,7 @@ export function NodeSettingsPanel({
   asrOptions: ModelOption[];
   ttsOptions: ModelOption[];
   visionOptions: ModelOption[];
+  dynamicVariableOptions: ModelOption[];
   workflowSettings: WorkflowSettings;
   onChange: (patch: WorkflowNodeData) => void;
 }) {
@@ -91,6 +94,8 @@ export function NodeSettingsPanel({
             ]
           : spec.type === "action"
             ? [{ id: "execution", label: "工具执行" }]
+            : spec.type === "update_state"
+              ? [{ id: "state", label: "状态更新" }]
             : spec.type === "handoff"
               ? [{ id: "handoff", label: "转交配置" }]
               : spec.type === "end"
@@ -114,6 +119,7 @@ export function NodeSettingsPanel({
             setArgumentsJson={setArgumentsJson}
             setAssignmentsJson={setAssignmentsJson}
             commitActionJson={commitActionJson}
+            dynamicVariableOptions={dynamicVariableOptions}
           />
         </PanelAnchorNavigation>
       );
@@ -130,6 +136,7 @@ export function NodeSettingsPanel({
         asrOptions={asrOptions}
         ttsOptions={ttsOptions}
         visionOptions={visionOptions}
+        dynamicVariableOptions={dynamicVariableOptions}
       />
     );
   }
@@ -262,6 +269,14 @@ export function NodeSettingsPanel({
           <MessageNodePanel draft={draft} set={set} setPatch={setPatch} />
         )}
 
+        {spec.type === "update_state" && (
+          <UpdateStateNodePanel
+            draft={draft}
+            set={set}
+            dynamicVariableOptions={dynamicVariableOptions}
+          />
+        )}
+
         {spec.type === "handoff" && (
           <NodeSelect
             label="转交类型"
@@ -306,6 +321,7 @@ function WorkflowNodePanelForm({
   setArgumentsJson,
   setAssignmentsJson,
   commitActionJson,
+  dynamicVariableOptions,
 }: {
   spec: RuntimeNodeSpec;
   draft: WorkflowNodeData;
@@ -318,6 +334,7 @@ function WorkflowNodePanelForm({
   setArgumentsJson: (value: string) => void;
   setAssignmentsJson: (value: string) => void;
   commitActionJson: (argumentsValue: string, assignmentsValue: string) => void;
+  dynamicVariableOptions: ModelOption[];
 }) {
   return (
     <div className="space-y-3">
@@ -341,6 +358,16 @@ function WorkflowNodePanelForm({
         <MessageNodePanel draft={draft} set={set} setPatch={setPatch} />
       )}
 
+      {spec.type === "update_state" && (
+        <PanelAnchor id="state">
+          <UpdateStateNodePanel
+            draft={draft}
+            set={set}
+            dynamicVariableOptions={dynamicVariableOptions}
+          />
+        </PanelAnchor>
+      )}
+
       {spec.type === "handoff" && (
         <PanelAnchor id="handoff">
           <SectionCard

frontend/src/components/workflow/panels/UpdateStateNodePanel.tsx

@@ -0,0 +1,79 @@
+"use client";
+
+import { Braces } from "lucide-react";
+import { useState } from "react";
+
+import { Button } from "@/components/ui/button";
+import { Textarea } from "@/components/ui/textarea";
+
+import { SectionCard } from "@/components/editor/section-card";
+import type { WorkflowNodeData } from "../specs";
+import type { ModelOption } from "../types";
+
+export function UpdateStateNodePanel({
+  draft,
+  set,
+  dynamicVariableOptions,
+}: {
+  draft: WorkflowNodeData;
+  set: (key: string, value: unknown) => void;
+  dynamicVariableOptions: ModelOption[];
+}) {
+  const [value, setValue] = useState(
+    JSON.stringify(draft.assignments ?? {}, null, 2),
+  );
+  const [error, setError] = useState("");
+
+  const commit = () => {
+    try {
+      const assignments = JSON.parse(value) as Record<string, unknown>;
+      if (
+        !assignments ||
+        Array.isArray(assignments) ||
+        typeof assignments !== "object"
+      ) {
+        throw new Error();
+      }
+      setError("");
+      set("assignments", assignments);
+    } catch {
+      setError("变量赋值必须是 JSON 对象");
+    }
+  };
+
+  return (
+    <SectionCard
+      icon={<Braces size={15} />}
+      title="状态更新"
+      description="一次性更新已声明的动态变量，然后继续执行后续节点"
+    >
+      <div>
+        <div className="mb-1.5 text-sm font-medium text-foreground">
+          变量赋值
+        </div>
+        <Textarea
+          rows={8}
+          value={value}
+          onChange={(event) => setValue(event.target.value)}
+          onBlur={commit}
+          placeholder={'{\n  "customer_name": "张三",\n  "confirmed": true\n}'}
+          className="field-sizing-fixed min-h-44 resize-y border-hairline-strong bg-background font-mono text-xs text-foreground placeholder:text-muted-soft"
+        />
+        {error && <p className="mt-1.5 text-xs text-destructive">{error}</p>}
+      </div>
+      <Button type="button" variant="outline" onClick={commit}>
+        应用变量赋值
+      </Button>
+      <div className="rounded-xl border border-hairline bg-canvas-soft p-3 text-xs leading-5 text-muted-foreground">
+        可用变量：
+        {dynamicVariableOptions.length
+          ? dynamicVariableOptions.map((option) => option.label).join("、")
+          : "暂无，请先在动态变量面板中声明"}
+      </div>
+      <p className="text-xs leading-5 text-muted-foreground">
+        值支持字符串、数字、布尔值，也可使用完整占位符，例如
+        {" {{source_name}}"}。
+      </p>
+    </SectionCard>
+  );
+}

frontend/src/components/workflow/specs.ts

@@ -3,7 +3,7 @@
 import * as LucideIcons from "lucide-react";
 import { Circle, type LucideIcon } from "lucide-react";
 
-import type { NodeSpecDto, TurnConfig } from "@/lib/api";
+import type { NodeSpecDto, SystemToolKind, TurnConfig } from "@/lib/api";
 import { defaultTurnConfig } from "@/lib/turn-config";
 
 export type WorkflowNodeType =
@@ -11,6 +11,7 @@ export type WorkflowNodeType =
   | "agent"
   | "message"
   | "action"
+  | "update_state"
   | "handoff"
   | "end";
 export type ContextPolicy = "inherit" | "fresh";
@@ -40,6 +41,8 @@ export type WorkflowNodeData = {
   contextPolicy?: ContextPolicy;
   inheritGlobalConfig?: boolean;
   entryMode?: AgentEntryMode;
+  systemTools?: SystemToolKind[];
+  stateVariableNames?: string[];
   toolIds?: string[];
   knowledgeBaseId?: string;
   knowledgeMode?: KnowledgeMode;
@@ -56,6 +59,7 @@ export type WorkflowNodeData = {
   arguments?: Record<string, unknown>;
   resultAssignmentMode?: ActionResultAssignmentMode;
   resultAssignments?: Record<string, string>;
+  assignments?: Record<string, unknown>;
   userInputPolicy?: ActionUserInputPolicy;
   speech?: string;
   /** Legacy field read only while an older graph is open in the editor. */
@@ -279,6 +283,8 @@ export function defaultGraph(): WorkflowGraph {
           contextPolicy: "inherit",
           inheritGlobalConfig: true,
           entryMode: "wait_user",
+          systemTools: [],
+          stateVariableNames: [],
         },
       },
       {

frontend/src/components/workflow/types.ts

@@ -33,6 +33,7 @@ export type WorkflowEditorProps = {
   };
   toolOptions?: ModelOption[];
   knowledgeOptions?: ModelOption[];
+  dynamicVariableOptions: ModelOption[];
   dynamicVariablesOpen: boolean;
   onDynamicVariablesOpenChange: (open: boolean) => void;
   dynamicVariablesPanel: ReactNode;

frontend/src/hooks/use-voice-preview.ts

@@ -612,6 +612,8 @@ export function useVoicePreview(
       onNodeActiveRef.current?.(msg.nodeId);
     } else if (msg.type === "workflow-variables") {
       setSessionVariables(publicVariableSnapshot(msg.variables));
+    } else if (msg.type === "session-variables") {
+      setSessionVariables(publicVariableSnapshot(msg.variables));
     } else if (msg.type === "call-ended") {
       endedByServerRef.current = true;
       setCallEnded(true);

frontend/src/lib/api.ts

@@ -216,6 +216,12 @@ export type StartupConfig = {
   } | null;
 };
 
+export type SystemToolKind =
+  | "end_conversation"
+  | "update_state"
+  | "skip_turn"
+  | "request_human_handoff";
+
 /** 后端 AssistantOut(宽表 STI:瘦字段平铺,workflow 用 graph)。apiKey 读时打码 */
 export type Assistant = {
   id: string;
@@ -226,6 +232,7 @@ export type Assistant = {
   enableInterrupt: boolean;
   turnConfig: TurnConfig;
   startup: StartupConfig;
+  systemTools: SystemToolKind[];
   visionEnabled: boolean;
   visionModelResourceId: string | null;
   modelResourceIds: Partial<Record<ModelType, string>>;
@@ -354,10 +361,11 @@ export type ToolParameter = {
   required: boolean;
 };
 
-export type EndCallToolDefinition = {
+export type SystemToolDefinition = {
   schemaVersion: number;
-  type: "end_call";
+  type: "system";
   config: {
+    kind: "end_conversation";
     messageType: "none" | "custom";
     customMessage: string;
     captureReason: boolean;
@@ -411,10 +419,10 @@ export type Tool = {
   id: string;
   name: string;
   functionName: string;
-  type: "end_call" | "http" | "mcp" | "client";
+  type: "system" | "http" | "mcp" | "client";
   description: string;
   definition:
-    | EndCallToolDefinition
+    | SystemToolDefinition
     | HttpToolDefinition
     | ClientToolDefinition
     | McpToolDefinition;

frontend/src/lib/system-tools.ts

@@ -0,0 +1,28 @@
+import type { SystemToolKind } from "@/lib/api";
+
+export const SYSTEM_TOOL_OPTIONS: Array<{
+  value: SystemToolKind;
+  label: string;
+  description: string;
+}> = [
+  {
+    value: "end_conversation",
+    label: "结束对话",
+    description: "模型可在用户告别或任务完成时主动结束通话。",
+  },
+  {
+    value: "update_state",
+    label: "更新状态",
+    description: "模型可更新明确授权的动态变量，记录本轮获得的信息。",
+  },
+  {
+    value: "skip_turn",
+    label: "跳过本轮",
+    description: "用户要求稍等、话未说完或输入只是噪音时保持静默。",
+  },
+  {
+    value: "request_human_handoff",
+    label: "请求人工接管",
+    description: "模型可提交人工接管请求；请求成功不代表人工已经接通。",
+  },
+];