diff --git a/crates/df-nodes/src/human_node.rs b/crates/df-nodes/src/human_node.rs
index e1b0c51..9f8f9a7 100644
--- a/crates/df-nodes/src/human_node.rs
+++ b/crates/df-nodes/src/human_node.rs
@@ -195,6 +195,40 @@ mod tests {
         assert_eq!(out.data["comment"], json!("好的"));
     }
 
+    #[tokio::test]
+    async fn request_is_emitted_to_bus() {
+        // B-03b-R8: 验证 HumanNode 真发出 HumanApprovalRequest 到事件总线
+        // (R6 修复前 :41 send 缺 await → Request 未进 channel，此测会超时失败)
+        let bus = EventBus::new();
+        let mut rx = bus.subscribe(); // subscribe 先于 execute send(broadcast 不回放)
+        let ctx = make_ctx(&bus, "exec-1", "node-h", json!({ "timeout_secs": 1 }));
+        let bus_clone = bus.clone();
+        let handle = tokio::spawn(async move { HumanNode.execute(ctx).await });
+
+        // execute send Request 后 rx 应收到
+        let received = tokio::time::timeout(Duration::from_millis(500), rx.recv()).await;
+        assert!(
+            received.is_ok(),
+            "应收到 HumanApprovalRequest(R6 Request 真发出)，实际超时"
+        );
+        match received.unwrap().unwrap() {
+            WorkflowEvent::HumanApprovalRequest {
+                execution_id,
+                node_id,
+                title,
+                ..
+            } => {
+                assert_eq!(execution_id, "exec-1");
+                assert_eq!(node_id, "node-h");
+                assert_eq!(title, "请确认");
+            }
+            other => panic!("期望 HumanApprovalRequest，收到 {:?}", other),
+        }
+        // 发 Response 让 execute 正常返回(防 task 泄漏)
+        send_response(&bus_clone, "exec-1", "node-h", "同意", None).await;
+        let _ = handle.await;
+    }
+
     #[tokio::test]
     async fn mismatched_execution_id_filtered_then_timeout() {
         // execution_id 不匹配：Response 被过滤，短超时验证 → Err 超时
diff --git a/src-tauri/src/commands/workflow.rs b/src-tauri/src/commands/workflow.rs
index d5cc7f1..9af3cec 100644
--- a/src-tauri/src/commands/workflow.rs
+++ b/src-tauri/src/commands/workflow.rs
@@ -132,11 +132,20 @@ pub async fn run_workflow(
         state_registry.lock().await.remove(&exec_id);
 
         // 执行失败时补发 WorkflowFailed（执行器内部只发 NodeFailed）
+        // failed_node 从状态机取首个失败/取消节点(R9⑪: 原 String::new() 空值)
         if let Some(error) = error {
+            use df_core::types::NodeStatus;
+            let failed_node = executor
+                .state_machine()
+                .snapshot()
+                .into_iter()
+                .find(|(_, s)| matches!(s, NodeStatus::Failed | NodeStatus::Cancelled))
+                .map(|(id, _)| id)
+                .unwrap_or_default();
             event_bus
                 .send(WorkflowEvent::WorkflowFailed {
                     error,
-                    failed_node: String::new(),
+                    failed_node,
                 })
                 .await;
         }
diff --git a/src/api/types.ts b/src/api/types.ts
index a6be189..73f38cb 100644
--- a/src/api/types.ts
+++ b/src/api/types.ts
@@ -121,10 +121,16 @@ export interface WorkflowRecord {
 }
 
 /** 工作流事件载荷（后端 emit 的结构） */
+/** 工作流事件类型字面量联合(对应后端 WorkflowEvent serde tag=type rename_all=snake_case，R7收窄防写错 type 字符串) */
+export type WorkflowEventType =
+  | 'node_started' | 'node_progress' | 'node_output' | 'node_completed' | 'node_failed'
+  | 'workflow_paused' | 'workflow_completed' | 'workflow_failed'
+  | 'human_approval_request' | 'human_approval_response'
+
 export interface WorkflowEventPayload {
   execution_id: string
   event: {
-    type: string
+    type: WorkflowEventType
     [key: string]: unknown
   }
 }