diff --git a/packages/workflow-engine/src/__tests__/agentAdapter.test.ts b/packages/workflow-engine/src/__tests__/agentAdapter.test.ts
index f868b55b4..0de4d92da 100644
--- a/packages/workflow-engine/src/__tests__/agentAdapter.test.ts
+++ b/packages/workflow-engine/src/__tests__/agentAdapter.test.ts
@@ -33,6 +33,7 @@ const CTX = {
   host: createHostHandle(null),
   signal: new AbortController().signal,
   runId: 'r',
+  agentId: 1,
 }
 
 test('resolve 默认走 default adapter，run 返回结果', async () => {
diff --git a/packages/workflow-engine/src/__tests__/hooks.test.ts b/packages/workflow-engine/src/__tests__/hooks.test.ts
index cef17ab0b..3f3324074 100644
--- a/packages/workflow-engine/src/__tests__/hooks.test.ts
+++ b/packages/workflow-engine/src/__tests__/hooks.test.ts
@@ -24,6 +24,14 @@ type CtxOverrides = Partial<{
   truncated: string[]
   agentAdapterRegistry: AgentAdapterRegistry
   loggerWarn: (msg: string) => void
+  // taskRegistrar 的 agent 级 abort 绑定（agent kill 桥接）。
+  // 提供后 buildCtx 注入到 ports.taskRegistrar；hooks.agent 把闭包塞进 adapterCtx。
+  registerAgentAbort: (
+    runId: string,
+    agentId: number,
+    ac: AbortController,
+  ) => void
+  unregisterAgentAbort: (runId: string, agentId: number) => void
 }>
 
 function buildCtx(overrides: CtxOverrides = {}): {
@@ -50,6 +58,12 @@ function buildCtx(overrides: CtxOverrides = {}): {
       fail: () => {},
       kill: () => {},
       pendingAction: () => overrides.pending ?? null,
+      ...(overrides.registerAgentAbort
+        ? { registerAgentAbort: overrides.registerAgentAbort }
+        : {}),
+      ...(overrides.unregisterAgentAbort
+        ? { unregisterAgentAbort: overrides.unregisterAgentAbort }
+        : {}),
     },
     journalStore: {
       read: async () => [],
@@ -424,3 +438,73 @@ test('agentAdapterRegistry resolve 抛错 → agent 上抛（workflow failed）'
   })
   await expect(hooks.agent('x')).rejects.toThrow()
 })
+
+// service.kill(runId, agentId) 桥接：hooks.agent 必须把 taskRegistrar 的
+// registerAgentAbort/unregisterAgentAbort 注入 adapterCtx（绑定当前 runId）。
+// backend 据此把 agentAbort controller 塞进 Map，service.kill 据 agentId 精确 abort。
+test('agentAdapter ctx 注入 registerAgentAbort/unregisterAgentAbort（绑定 runId 转发 taskRegistrar）', async () => {
+  const registered: Array<{
+    runId: string
+    agentId: number
+    controller: AbortController
+  }> = []
+  const unregistered: Array<{ runId: string; agentId: number }> = []
+  // 捕获 hooks 传给 adapter 的 ctx（验证 register/unregister 已注入且绑定 runId）
+  let capturedCtx: {
+    registerAgentAbort?: (id: number, ac: AbortController) => void
+    unregisterAgentAbort?: (id: number) => void
+    agentId: number
+    runId: string
+  } | null = null
+  const registry = new AgentAdapterRegistry()
+    .register({
+      id: 'ad',
+      capabilities: { structuredOutput: true },
+      async run(_params, ctx) {
+        capturedCtx = ctx
+        return { kind: 'ok', output: 'x', usage: { outputTokens: 1 } }
+      },
+    })
+    .default('ad')
+  const { hooks } = buildCtx({
+    agentAdapterRegistry: registry,
+    registerAgentAbort: (runId, agentId, controller) =>
+      registered.push({ runId, agentId, controller }),
+    unregisterAgentAbort: (runId, agentId) =>
+      unregistered.push({ runId, agentId }),
+  })
+  await hooks.agent('x')
+  // ctx 含 register/unregister（闭包绑定 runId='r1'）
+  expect(capturedCtx).not.toBeNull()
+  expect(typeof capturedCtx!.registerAgentAbort).toBe('function')
+  expect(typeof capturedCtx!.unregisterAgentAbort).toBe('function')
+  // 模拟 backend 调用：注入的闭包把 (agentId, controller) 转发到 taskRegistrar，
+  // 并自动补 runId='r1'（backend 不需要知道 runId）
+  const ac = new AbortController()
+  capturedCtx!.registerAgentAbort!(7, ac)
+  capturedCtx!.unregisterAgentAbort!(7)
+  expect(registered).toEqual([{ runId: 'r1', agentId: 7, controller: ac }])
+  expect(unregistered).toEqual([{ runId: 'r1', agentId: 7 }])
+})
+
+test('taskRegistrar 未提供 registerAgentAbort → adapterCtx 也不含（hooks 不报错）', async () => {
+  // 不传 registerAgentAbort/unregisterAgentAbort overrides → buildCtx 也不注入 taskRegistrar
+  // hooks 用 optional chaining 跳过，adapterCtx 不含这两个字段
+  let capturedCtx: object | null = null
+  const registry = new AgentAdapterRegistry()
+    .register({
+      id: 'ad',
+      capabilities: { structuredOutput: true },
+      async run(_params, ctx) {
+        capturedCtx = ctx
+        return { kind: 'ok', output: 'x', usage: { outputTokens: 1 } }
+      },
+    })
+    .default('ad')
+  const { hooks } = buildCtx({ agentAdapterRegistry: registry })
+  await hooks.agent('x')
+  expect(capturedCtx).not.toBeNull()
+  expect(
+    (capturedCtx! as Record<string, unknown>).registerAgentAbort,
+  ).toBeUndefined()
+})
diff --git a/packages/workflow-engine/src/agentAdapter.ts b/packages/workflow-engine/src/agentAdapter.ts
index 193ae463a..7639414ea 100644
--- a/packages/workflow-engine/src/agentAdapter.ts
+++ b/packages/workflow-engine/src/agentAdapter.ts
@@ -25,11 +25,29 @@ export type AgentAdapterContext = {
   signal: AbortSignal
   /** 当前 workflow runId（日志/追踪用）。 */
   runId: string
+  /**
+   * 引擎层 agent 序号（hooks.agentIdSeq 递增；面板 RunProgress.agents[].id 同源）。
+   * 注意：与 backend 内部创建的 core AgentId（字符串，子 agent 跟踪用）是两个不同概念，
+   * 不可混用。本字段用于 registerAgentAbort/unregisterAgentAbort 的 key，让 service
+   * .kill(runId, agentId) 能精确路由到 backend 创建的 AbortController。
+   */
+  agentId: number
   /**
    * 运行中进度上报（后端循环累计 token/tool 时调用）。可选：独立后端可不实现；
    * 引擎据此发 agent_progress 事件（闭包带 agentId/runId 关联），面板实时刷新。
    */
   onProgress?: (update: AgentProgressUpdate) => void
+  /**
+   * 注册 agent 级 AbortController（可选）。后端创建 controller 后调此注入 Map，
+   * 让 service.kill(runId, agentId) 能精确中断单个 agent 而不影响其他。
+   * 由 hooks.agent 在 backend.run 调用前注入。
+   */
+  registerAgentAbort?: (agentId: number, ac: AbortController) => void
+  /**
+   * 注销 agent 级 AbortController（agent 完成或失败时调；幂等）。
+   * 与 registerAgentAbort 配对。
+   */
+  unregisterAgentAbort?: (agentId: number) => void
 }
 
 /**
diff --git a/packages/workflow-engine/src/engine/hooks.ts b/packages/workflow-engine/src/engine/hooks.ts
index a16bf9533..51472f467 100644
--- a/packages/workflow-engine/src/engine/hooks.ts
+++ b/packages/workflow-engine/src/engine/hooks.ts
@@ -117,13 +117,45 @@ export function makeHooks(
       const onProgress = (update: AgentProgressUpdate): void => {
         emit({ type: 'agent_progress', agentId, label, phase, ...update })
       }
-      const result = registry
-        ? await registry.resolve(params).run(params, {
+      // 注入 agent 级 AbortController 注册/注销：backend 创建 controller 后调
+      // registerAgentAbort 注入 ports 层 bindings，service.kill(runId, agentId) 据此
+      // 精确中断单个 agent。registry 不存在（agentRunner 兜底路径）时无 backend 中间层，
+      // ports 层 agentAbortControllers 永远空——单 agent kill 在该路径降级为 no-op。
+      const adapterCtx = registry
+        ? {
             host: ctx.host,
             signal: ctx.signal,
             runId: ctx.runId,
+            agentId,
             onProgress,
-          })
+            ...(ctx.ports.taskRegistrar.registerAgentAbort
+              ? {
+                  registerAgentAbort: (
+                    id: number,
+                    ac: AbortController,
+                  ): void => {
+                    ctx.ports.taskRegistrar.registerAgentAbort?.(
+                      ctx.runId,
+                      id,
+                      ac,
+                    )
+                  },
+                }
+              : {}),
+            ...(ctx.ports.taskRegistrar.unregisterAgentAbort
+              ? {
+                  unregisterAgentAbort: (id: number): void => {
+                    ctx.ports.taskRegistrar.unregisterAgentAbort?.(
+                      ctx.runId,
+                      id,
+                    )
+                  },
+                }
+              : {}),
+          }
+        : null
+      const result = registry
+        ? await registry.resolve(params).run(params, adapterCtx!)
         : await ctx.ports.agentRunner.runAgentToResult(params, ctx.host)
       if (result.kind === 'ok') {
         ctx.resources.budget.addOutputTokens(result.usage.outputTokens)
diff --git a/packages/workflow-engine/src/ports.ts b/packages/workflow-engine/src/ports.ts
index 1b4778a20..140355c9e 100644
--- a/packages/workflow-engine/src/ports.ts
+++ b/packages/workflow-engine/src/ports.ts
@@ -69,6 +69,21 @@ export type TaskRegistrar = {
   complete(runId: string, summary?: string): void
   fail(runId: string, error: string): void
   kill(runId: string): void
+  /**
+   * 注册 agent 级 AbortController。backend 启动 agent 时调用，让 service
+   * .kill(runId, agentId) 能精确中断单个 agent（不影响同 run 其他 agent）。
+   * 幂等：同 agentId 重复注册覆盖。
+   */
+  registerAgentAbort?(runId: string, agentId: number, ac: AbortController): void
+  /**
+   * 注销 agent 级 AbortController（agent 完成/失败时调；幂等）。
+   */
+  unregisterAgentAbort?(runId: string, agentId: number): void
+  /**
+   * 中断单个 agent。返回是否命中（false = agent 已完成/不存在）。
+   * 不影响同 run 其他 agent，workflow 继续跑（被中断 agent 返回 dead → null）。
+   */
+  killAgent?(runId: string, agentId: number): boolean
   /** 返回当前待处理的 skip/retry 动作，或 null。 */
   pendingAction(runId: string): { kind: 'skip' | 'retry' } | null
 }
diff --git a/src/workflow/__tests__/claudeCodeBackend.test.ts b/src/workflow/__tests__/claudeCodeBackend.test.ts
index e16666098..1e396768f 100644
--- a/src/workflow/__tests__/claudeCodeBackend.test.ts
+++ b/src/workflow/__tests__/claudeCodeBackend.test.ts
@@ -76,6 +76,7 @@ mock.module('src/utils/worktree.js', () => ({
   },
 }))
 
+import { WorkflowAbortedError } from '@claude-code-best/workflow-engine'
 import {
   claudeCodeBackend,
   resolveAgentDefinition,
@@ -108,6 +109,7 @@ function ctx() {
     }),
     signal: new AbortController().signal,
     runId: 'r1',
+    agentId: 1,
   }
 }
 
@@ -188,6 +190,85 @@ test('runAgent 抛错 → dead', async () => {
   expect(res.kind).toBe('dead')
 })
 
+// 下面三组测试覆盖 'x' 无效修复：backend 必须把 ctx.signal 桥接到 runAgent.override
+// .abortController，并把 AbortError 识别为 abort（throw WorkflowAbortedError，而非吞成 dead）。
+// 还要验证 registerAgentAbort 注入，让 service.kill(runId, agentId) 能精确中断单个 agent。
+
+test('ctx.signal 预 abort → backend 桥接：override.abortController.signal.aborted=true', async () => {
+  // 用 capturedOverride 暴露 backend 创建的 agentAbort（mock 收到的 override.abortController）
+  let capturedController: AbortController | undefined
+  mock.module(
+    '@claude-code-best/builtin-tools/tools/AgentTool/runAgent.js',
+    () => ({
+      runAgent: async function* (opts: {
+        override?: { abortController?: AbortController }
+      }) {
+        capturedController = opts.override?.abortController
+        yield {
+          type: 'assistant',
+          message: { content: [{ type: 'text', text: 'x' }] },
+        }
+      },
+    }),
+  )
+  const parentAbort = new AbortController()
+  parentAbort.abort()
+  // mock 不抛 → backend 走正常返回路径；但桥接 `if (ctx.signal.aborted) agentAbort.abort()`
+  // 已同步触发，capturedController.signal.aborted 必为 true（kill 桥接根因）
+  await claudeCodeBackend.run(
+    { prompt: 'pre-aborted' },
+    { ...ctx(), signal: parentAbort.signal },
+  )
+  expect(capturedController?.signal.aborted).toBe(true)
+})
+
+test('runAgent 抛 AbortError → backend throw WorkflowAbortedError（不吞成 dead）', async () => {
+  mock.module(
+    '@claude-code-best/builtin-tools/tools/AgentTool/runAgent.js',
+    () => ({
+      // biome-ignore lint/correctness/useYield: 故意抛 AbortError 测识别分支
+      runAgent: async function* () {
+        const e = new Error('aborted by parent')
+        e.name = 'AbortError'
+        throw e
+      },
+    }),
+  )
+  await expect(
+    claudeCodeBackend.run({ prompt: 'abort' }, ctx()),
+  ).rejects.toBeInstanceOf(WorkflowAbortedError)
+})
+
+test('registerAgentAbort/unregisterAgentAbort 注入：key=ctx.agentId（数字），controller 来自桥接', async () => {
+  // 恢复默认 mock（上一个测试把它改成抛 AbortError 了）
+  mock.module(
+    '@claude-code-best/builtin-tools/tools/AgentTool/runAgent.js',
+    () => ({
+      runAgent: async function* () {
+        yield {
+          type: 'assistant',
+          message: { content: [{ type: 'text', text: 'agent-text' }] },
+        }
+      },
+    }),
+  )
+  const registered: Array<{ id: number; controller: AbortController }> = []
+  const unregistered: number[] = []
+  await claudeCodeBackend.run(
+    { prompt: 'wiring' },
+    {
+      ...ctx(),
+      agentId: 42,
+      registerAgentAbort: (id, ac) => registered.push({ id, controller: ac }),
+      unregisterAgentAbort: id => unregistered.push(id),
+    },
+  )
+  expect(registered).toHaveLength(1)
+  expect(registered[0]?.id).toBe(42) // 引擎数字 agentId（非 coreAgentId 字符串）
+  expect(registered[0]?.controller).toBeInstanceOf(AbortController)
+  expect(unregistered).toEqual([42]) // finally 清理幂等
+})
+
 test('id 与 capabilities 形状', () => {
   expect(claudeCodeBackend.id).toBe('claude-code')
   expect(claudeCodeBackend.capabilities.structuredOutput).toBe(true)
diff --git a/src/workflow/__tests__/ports.test.ts b/src/workflow/__tests__/ports.test.ts
index 95847da6c..630f3177f 100644
--- a/src/workflow/__tests__/ports.test.ts
+++ b/src/workflow/__tests__/ports.test.ts
@@ -93,6 +93,95 @@ test('taskRegistrar.register/complete/kill 经 RunBinding 路由（真 setAppSta
   ports.taskRegistrar.kill(runId)
 })
 
+// agent 级 kill 桥接：register → killAgent 精确中断；kill(runId) 顺带 abort 所有 agent。
+test('taskRegistrar agentAbortControllers：register/killAgent 精确中断；kill(runId) 批量 abort', () => {
+  const bus = createProgressBus()
+  const store = createProgressStoreFromBus(bus)
+  const ports = createWorkflowPorts({ bus, store })
+  // 实现always provides these — cast 把 optional 拍平为 required（避免每行 ! 断言）
+  const tr = ports.taskRegistrar as Required<typeof ports.taskRegistrar>
+
+  const state = { tasks: {} } as unknown as AppState
+  const setAppState: SetAppState = f => {
+    Object.assign(state, f(state))
+  }
+  const hostCtx = ports.hostFactory({
+    context: { agentId: 'a-1', toolUseId: 'tu-1', setAppState },
+    canUseTool: (() => Promise.resolve({ behavior: 'allow' })) as never,
+    parentMessage: {} as never,
+  })
+  const { runId } = tr.register(
+    {
+      workflowName: 'wf',
+      summary: 'summary',
+      workflowFile: 'wf.ts',
+      toolUseId: 'tu-1',
+    },
+    hostCtx.handle,
+  )
+
+  // 注册两个 agent 的 AbortController（模拟 backend 在启动 agent 时调用）
+  const ac1 = new AbortController()
+  const ac2 = new AbortController()
+  tr.registerAgentAbort(runId, 1, ac1)
+  tr.registerAgentAbort(runId, 2, ac2)
+  expect(ac1.signal.aborted).toBe(false)
+  expect(ac2.signal.aborted).toBe(false)
+
+  // killAgent 精确中断 agent #1：仅 ac1 abort，ac2 不受影响
+  expect(tr.killAgent(runId, 1)).toBe(true)
+  expect(ac1.signal.aborted).toBe(true)
+  expect(ac2.signal.aborted).toBe(false)
+  // 重复 kill 同 agent：controller 已 delete，返回 false（幂等）
+  expect(tr.killAgent(runId, 1)).toBe(false)
+
+  // 未知 agentId / 未知 runId 安全返回 false
+  expect(tr.killAgent(runId, 999)).toBe(false)
+  expect(tr.killAgent('nope', 1)).toBe(false)
+
+  // kill(runId) 批量 abort 剩余 agent（ac2）
+  tr.kill(runId)
+  expect(ac2.signal.aborted).toBe(true)
+
+  // run 终态后 binding 已回收：再 killAgent 返回 false
+  expect(tr.killAgent(runId, 2)).toBe(false)
+})
+
+test('unregisterAgentAbort 从 Map 删除（backend finally 清理幂等）', () => {
+  const bus = createProgressBus()
+  const store = createProgressStoreFromBus(bus)
+  const ports = createWorkflowPorts({ bus, store })
+  const tr = ports.taskRegistrar as Required<typeof ports.taskRegistrar>
+
+  const state = { tasks: {} } as unknown as AppState
+  const setAppState: SetAppState = f => {
+    Object.assign(state, f(state))
+  }
+  const hostCtx = ports.hostFactory({
+    context: { agentId: 'a-1', toolUseId: 'tu-1', setAppState },
+    canUseTool: (() => Promise.resolve({ behavior: 'allow' })) as never,
+    parentMessage: {} as never,
+  })
+  const { runId } = tr.register(
+    {
+      workflowName: 'wf',
+      summary: 'summary',
+      workflowFile: 'wf.ts',
+      toolUseId: 'tu-1',
+    },
+    hostCtx.handle,
+  )
+  const ac = new AbortController()
+  tr.registerAgentAbort(runId, 5, ac)
+  // 注销后 killAgent 无目标，返 false（不抛）
+  tr.unregisterAgentAbort(runId, 5)
+  expect(tr.killAgent(runId, 5)).toBe(false)
+  // 重复注销幂等（backend finally 不抛）
+  expect(() => tr.unregisterAgentAbort(runId, 5)).not.toThrow()
+  // 未知 runId 安全 no-op
+  expect(() => tr.unregisterAgentAbort('nope', 5)).not.toThrow()
+})
+
 test('hostFactory.cwd 与 journalStore 同根（getProjectRoot）—— 修复 K 回归', () => {
   // 历史 bug：hostFactory.cwd 用 getCwd()、journalStore 用 getProjectRoot()，
   // 用户进入 worktree/子目录时两者不同 → 命名 workflow 解析与 journal 落盘不同步。
diff --git a/src/workflow/__tests__/service.test.ts b/src/workflow/__tests__/service.test.ts
index 216090c53..52e138251 100644
--- a/src/workflow/__tests__/service.test.ts
+++ b/src/workflow/__tests__/service.test.ts
@@ -27,6 +27,14 @@ type RegistrarCall =
   | { kind: 'complete'; runId: string; summary?: string }
   | { kind: 'fail'; runId: string; error?: string }
   | { kind: 'kill'; runId: string }
+  | {
+      kind: 'registerAgentAbort'
+      runId: string
+      agentId: number
+      controller: AbortController
+    }
+  | { kind: 'unregisterAgentAbort'; runId: string; agentId: number }
+  | { kind: 'killAgent'; runId: string; agentId: number }
 
 function fakePorts(
   opts: {
@@ -41,14 +49,18 @@ function fakePorts(
   ports: WorkflowPorts
   store: ReturnType<typeof createProgressStoreFromBus>
   killed: string[]
-  /** taskRegistrar 调用记录（complete/fail/kill）。 */
+  /** taskRegistrar 调用记录（complete/fail/kill/registerAgentAbort/...）。 */
   calls: RegistrarCall[]
+  /** runId → (agentId → AbortController)。测试模拟 backend 注册用。 */
+  agentBindings: Map<string, Map<number, AbortController>>
 } {
   const bus = createProgressBus()
   const store = createProgressStoreFromBus(bus)
   const killed: string[] = []
   const calls: RegistrarCall[] = []
   const bindings = new Map<string, { abort: AbortController }>()
+  // agentId → AbortController（每个 runId 独立）。killAgent 据此精确中断。
+  const agentBindings = new Map<string, Map<number, AbortController>>()
   let seq = 0
   const ports = {
     // hostFactory 实际不被 service.launch 路径调用（service 自建 host handle），
@@ -93,6 +105,7 @@ function fakePorts(
         seq += 1
         const runId = `run-${seq}`
         bindings.set(runId, { abort })
+        agentBindings.set(runId, new Map())
         return { runId, signal: abort.signal }
       },
       complete: (runId: string, summary?: string) => {
@@ -106,6 +119,31 @@ function fakePorts(
         calls.push({ kind: 'kill', runId })
         bindings.get(runId)?.abort.abort()
       },
+      registerAgentAbort: (
+        runId: string,
+        agentId: number,
+        controller: AbortController,
+      ) => {
+        calls.push({
+          kind: 'registerAgentAbort',
+          runId,
+          agentId,
+          controller,
+        })
+        agentBindings.get(runId)?.set(agentId, controller)
+      },
+      unregisterAgentAbort: (runId: string, agentId: number) => {
+        calls.push({ kind: 'unregisterAgentAbort', runId, agentId })
+        agentBindings.get(runId)?.delete(agentId)
+      },
+      killAgent: (runId: string, agentId: number) => {
+        calls.push({ kind: 'killAgent', runId, agentId })
+        const ac = agentBindings.get(runId)?.get(agentId)
+        if (!ac) return false
+        ac.abort()
+        agentBindings.get(runId)!.delete(agentId)
+        return true
+      },
       pendingAction: () => null,
     },
     journalStore: {
@@ -120,7 +158,7 @@ function fakePorts(
       warn: () => {},
     },
   } as unknown as WorkflowPorts
-  return { ports, store, killed, calls }
+  return { ports, store, killed, calls, agentBindings }
 }
 
 const stubTUC = { agentId: 'a1', toolUseId: 'tu' } as never
@@ -184,6 +222,33 @@ test('kill 走 taskRegistrar.kill', async () => {
   expect(killed).toContain(runId)
 })
 
+test('killAgent 走 taskRegistrar.killAgent：精确中断单个 agent', async () => {
+  __resetWorkflowServiceForTests()
+  const { ports, store, calls, agentBindings } = fakePorts()
+  const svc = makeService(ports, store)
+  const { runId } = await svc.launch(
+    { script: `return agent('x')` },
+    stubTUC,
+    stubCanUseTool,
+  )
+  // 模拟 backend 启动 agent 时注册 AbortController
+  const ac = new AbortController()
+  agentBindings.get(runId)!.set(7, ac)
+  // service.killAgent 路由到 taskRegistrar.killAgent，后者真 abort 对应 controller
+  expect(svc.killAgent(runId, 7)).toBe(true)
+  expect(ac.signal.aborted).toBe(true)
+  expect(
+    calls.some(
+      c => c.kind === 'killAgent' && c.runId === runId && c.agentId === 7,
+    ),
+  ).toBe(true)
+  // 已 abort 后 controller 从 Map 删除：再次 killAgent 同 agent 返 false（幂等）
+  expect(svc.killAgent(runId, 7)).toBe(false)
+  // 未知 agentId / 未知 runId 安全返 false
+  expect(svc.killAgent(runId, 999)).toBe(false)
+  expect(svc.killAgent('nope', 1)).toBe(false)
+})
+
 test('listRuns/subscribe 来自 store', () => {
   __resetWorkflowServiceForTests()
   const { ports, store } = fakePorts()
diff --git a/src/workflow/__tests__/useWorkflowKeyboard.test.ts b/src/workflow/__tests__/useWorkflowKeyboard.test.ts
index 9ea8fa55e..196d90138 100644
--- a/src/workflow/__tests__/useWorkflowKeyboard.test.ts
+++ b/src/workflow/__tests__/useWorkflowKeyboard.test.ts
@@ -11,12 +11,27 @@ test('q / Esc → quit', () => {
   expect(routeWorkflowKey('', { escape: true })).toBe('quit')
 })
 
-test('x → kill；r → resume；n → newRun', () => {
-  expect(routeWorkflowKey('x', {})).toBe('kill')
+test('x → killAgent；K → killWorkflow；r → resume；n → newRun', () => {
+  expect(routeWorkflowKey('x', {})).toBe('killAgent')
+  expect(routeWorkflowKey('K', {})).toBe('killWorkflow')
   expect(routeWorkflowKey('r', {})).toBe('resume')
   expect(routeWorkflowKey('n', {})).toBe('newRun')
 })
 
+test('confirm 模式：y/Enter → confirmYes；n/Esc/q → confirmNo；其他键 → null', () => {
+  expect(routeWorkflowKey('y', {}, 'confirm')).toBe('confirmYes')
+  expect(routeWorkflowKey('Y', {}, 'confirm')).toBe('confirmYes')
+  expect(routeWorkflowKey('', { return: true }, 'confirm')).toBe('confirmYes')
+  expect(routeWorkflowKey('n', {}, 'confirm')).toBe('confirmNo')
+  expect(routeWorkflowKey('N', {}, 'confirm')).toBe('confirmNo')
+  expect(routeWorkflowKey('', { escape: true }, 'confirm')).toBe('confirmNo')
+  expect(routeWorkflowKey('q', {}, 'confirm')).toBe('confirmNo')
+  // confirm 模式吞掉导航/编辑键，防误触
+  expect(routeWorkflowKey('x', {}, 'confirm')).toBeNull()
+  expect(routeWorkflowKey('', { tab: true }, 'confirm')).toBeNull()
+  expect(routeWorkflowKey('', { upArrow: true }, 'confirm')).toBeNull()
+})
+
 test('←/→ 切焦点列；↑/↓ 列内移动', () => {
   expect(routeWorkflowKey('', { leftArrow: true })).toBe('focusLeft')
   expect(routeWorkflowKey('', { rightArrow: true })).toBe('focusRight')
diff --git a/src/workflow/backends/claudeCodeBackend.ts b/src/workflow/backends/claudeCodeBackend.ts
index b9af9193d..d208d1870 100644
--- a/src/workflow/backends/claudeCodeBackend.ts
+++ b/src/workflow/backends/claudeCodeBackend.ts
@@ -5,6 +5,7 @@ import {
   type AgentAdapterContext,
   type AgentRunParams,
   type AgentRunResult,
+  WorkflowAbortedError,
 } from '@claude-code-best/workflow-engine'
 import { assembleToolPool } from '../../tools.js'
 import { finalizeAgentTool } from '@claude-code-best/builtin-tools/tools/AgentTool/agentToolUtils.js'
@@ -146,14 +147,16 @@ export const claudeCodeBackend: AgentAdapter = {
     const appState = toolUseContext.getAppState()
     const agentDef = resolveAgentDefinition(params.agentType, toolUseContext)
     const model = mapWorkflowModel(params.model)
-    const agentId = createAgentId()
+    // coreAgentId：core 层子 agent 跟踪 ID（字符串，runAgent 内部用）。
+    // 与 ctx.agentId（引擎 number seq，用于面板/killAgent 路由）是两个不同概念，不可混用。
+    const coreAgentId = createAgentId()
 
     // isolation:'worktree' — 在独立 git worktree 里跑 agent，并发写互不冲突。
     let worktreeInfo: WorkflowWorktreeInfo | null = null
     if (params.isolation === 'worktree') {
       try {
         worktreeInfo = await createAgentWorktree(
-          makeWorkflowWorktreeSlug(ctx.runId, agentId),
+          makeWorkflowWorktreeSlug(ctx.runId, coreAgentId),
         )
       } catch (e) {
         // fail-closed：隔离未达成不静默退化为共享 cwd（否则并发写数据竞争）
@@ -170,6 +173,21 @@ export const claudeCodeBackend: AgentAdapter = {
           runWithCwdOverride(worktreeInfo!.worktreePath, fn)
       : <T>(fn: () => T): T => fn()
 
+    // 桥接 ctx.signal → runAgent.override.abortController。否则 workflow 被 kill
+    // 时 runAgent 不知道（'x' 无效根因）：abort 信号到不了内部 fetch，agent 跑到完成。
+    // 单 agent kill 走 service.kill(runId, agentId) → ports.taskRegistrar.killAgent →
+    // agentAbortControllers.get(agentId).abort()；同一 controller 接管两条路径。
+    const agentAbort = new AbortController()
+    const onParentAbort = (): void => agentAbort.abort()
+    if (ctx.signal.aborted) {
+      agentAbort.abort()
+    } else {
+      ctx.signal.addEventListener('abort', onParentAbort, { once: true })
+    }
+    if (typeof ctx.registerAgentAbort === 'function') {
+      ctx.registerAgentAbort(ctx.agentId, agentAbort)
+    }
+
     const workerPermissionContext = {
       ...appState.toolPermissionContext,
       mode: agentDef.permissionMode ?? 'acceptEdits',
@@ -201,9 +219,10 @@ export const claudeCodeBackend: AgentAdapter = {
           isAsync: true,
           querySource: toolUseContext.options.querySource ?? 'workflow',
           availableTools: workerTools,
-          override: { agentId },
+          // override 同一对象：coreAgentId（core 子 agent 跟踪）+ abortController（kill 桥接）。
           // runAgent 的 model 是顶层 ModelAlias；workflow 的 model 是任意别名串，
           // 类型上不兼容，运行时由 provider 层解析。双重断言透传（优于 as any/never）。
+          override: { agentId: coreAgentId, abortController: agentAbort },
           ...(model ? { model: model as unknown as ModelAlias } : {}),
           ...(worktreeInfo ? { worktreePath: worktreeInfo.worktreePath } : {}),
         })) {
@@ -224,12 +243,23 @@ export const claudeCodeBackend: AgentAdapter = {
         }
       })
     } catch (e) {
+      // abort（kill workflow / kill agent）：识别后必须重抛 WorkflowAbortedError，
+      // 否则 hooks.agent 会把 abort 当作普通失败吞成 dead，workflow 不知道被 kill
+      // （kill 路径 'x' 无效的另一面：信号虽然到了，但结果被伪装成正常完成）。
+      if (agentAbort.signal.aborted || (e as Error)?.name === 'AbortError') {
+        throw new WorkflowAbortedError()
+      }
       logForDebugging(
         `workflow sub-agent error (${agentDef.agentType}): ${(e as Error).message}`,
       )
       logEvent('tengu_workflow_agent', { ok: 0 })
       return { kind: 'dead' }
     } finally {
+      // 清理（幂等）：listener removeEventListener / Map.delete 重复调用安全。
+      if (typeof ctx.unregisterAgentAbort === 'function') {
+        ctx.unregisterAgentAbort(ctx.agentId)
+      }
+      ctx.signal.removeEventListener('abort', onParentAbort)
       if (worktreeInfo) {
         const info = worktreeInfo
         worktreeInfo = null
@@ -237,7 +267,7 @@ export const claudeCodeBackend: AgentAdapter = {
       }
     }
 
-    const finalized = finalizeAgentTool(messages, agentId, {
+    const finalized = finalizeAgentTool(messages, coreAgentId, {
       prompt: params.prompt,
       resolvedAgentModel: toolUseContext.options.mainLoopModel,
       isBuiltInAgent: isBuiltInAgent(agentDef),
diff --git a/src/workflow/panel/WorkflowsPanel.tsx b/src/workflow/panel/WorkflowsPanel.tsx
index 19e383bf9..be6a3570a 100644
--- a/src/workflow/panel/WorkflowsPanel.tsx
+++ b/src/workflow/panel/WorkflowsPanel.tsx
@@ -1,5 +1,5 @@
 import React, { useEffect, useState, useSyncExternalStore } from 'react';
-import { Box, Text, useAnimationFrame } from '@anthropic/ink';
+import { Box, Dialog, Text, useAnimationFrame } from '@anthropic/ink';
 import type { Theme } from '@anthropic/ink';
 import type { LocalJSXCommandContext, LocalJSXCommandOnDone } from '../../types/command.js';
 import { getWorkflowService } from '../service.js';
@@ -47,6 +47,9 @@ export function WorkflowsPanel({
   const [focusColumn, setFocusColumn] = useState<FocusColumn>('phases');
   const [selectedPhaseIndex, setSelectedPhaseIndex] = useState(0);
   const [selectedAgentIndex, setSelectedAgentIndex] = useState(0);
+  // kill 二次确认。null = 无弹窗；'workflow' = 杀整个 run；'agent' = 杀当前选中 agent。
+  // 非 null 时键盘进入 confirm 模式（仅 y/Enter/n/Esc/q 响应）。
+  const [confirmKill, setConfirmKill] = useState<null | 'agent' | 'workflow'>(null);
 
   // mount 时触发一次扫盘 hydrate 历史 run（service 内部 persistedLoaded flag 守护幂等）。
   // 重 mount/重渲染不会重复扫盘（flag 进程单例守护）。svc 引用稳定（getWorkflowService 单例）。
@@ -110,8 +113,18 @@ export function WorkflowsPanel({
       if (focusColumn === 'phases') setSelectedPhaseIndex(s => clampSelected(s + 1, phaseRowCount));
       else setSelectedAgentIndex(s => clampSelected(s + 1, visibleAgents.length));
     },
-    killFocused: () => {
-      if (focused) svc.kill(focused.runId);
+    killAgent: () => {
+      // 仅在 agents 列聚焦时弹 agent 确认（在 phases 列按 x 无目标，no-op）。
+      // 选中 agent 由 visibleAgents[clampedAgent] 决定；保存到 confirmKill 后由
+      // confirmYes 实际执行——避免在两次渲染间 visibleAgents 变化导致误杀。
+      if (focusColumn !== 'agents' || !focused) return;
+      const agent = visibleAgents[clampedAgent];
+      if (!agent) return;
+      setConfirmKill('agent');
+    },
+    killWorkflow: () => {
+      if (!focused) return;
+      setConfirmKill('workflow');
     },
     resumeFocused: () => {
       if (!focused) return;
@@ -125,9 +138,27 @@ export function WorkflowsPanel({
         .catch(e => onDone(`resume failed: ${(e as Error).message}`));
     },
     newRun: () => onDone('Tip: start a named workflow with /<name>, or pass name via the Workflow tool.'),
-    quit: () => onDone(),
+    quit: () => {
+      // confirm 模式下 q = 取消确认（routeWorkflowKey 已路由到 confirmNo）；
+      // 非 confirm 模式才真退出面板。
+      if (confirmKill !== null) {
+        setConfirmKill(null);
+        return;
+      }
+      onDone();
+    },
+    confirmYes: () => {
+      if (confirmKill === 'workflow' && focused) {
+        svc.kill(focused.runId);
+      } else if (confirmKill === 'agent' && focused) {
+        const agent = visibleAgents[clampedAgent];
+        if (agent) svc.killAgent(focused.runId, agent.id);
+      }
+      setConfirmKill(null);
+    },
+    confirmNo: () => setConfirmKill(null),
   };
-  useWorkflowKeyboard(handlers);
+  useWorkflowKeyboard(handlers, confirmKill !== null ? 'confirm' : 'normal');
 
   const running = runs.filter(r => r.status === 'running').length;
   const done = runs.length - running;
@@ -182,8 +213,31 @@ export function WorkflowsPanel({
       </Box>
 
       <Box marginTop={1}>
-        <Text color="subtle">Tab switch run · ←/→ focus · ↑/↓ move · x kill · r resume · q quit</Text>
+        <Text color="subtle">
+          {confirmKill !== null
+            ? 'Confirm: y kill · n/Esc cancel'
+            : 'Tab switch run · ←/→ focus · ↑/↓ move · x kill agent · K kill workflow · r resume · q quit'}
+        </Text>
       </Box>
+
+      {confirmKill !== null ? (
+        <Dialog
+          title={
+            confirmKill === 'workflow'
+              ? `Kill workflow "${focused?.workflowName ?? ''}"?`
+              : `Kill agent "${visibleAgents[clampedAgent]?.label ?? ''}"?`
+          }
+          subtitle={
+            confirmKill === 'workflow'
+              ? 'All in-flight agents will be aborted. Resume will replay from journal.'
+              : 'Only this agent aborts; other agents in the workflow keep running.'
+          }
+          onCancel={() => setConfirmKill(null)}
+          color="warning"
+        >
+          <Text color="subtle">Press y to confirm, or n/Esc to cancel.</Text>
+        </Dialog>
+      ) : null}
     </Box>
   );
 }
diff --git a/src/workflow/panel/useWorkflowKeyboard.ts b/src/workflow/panel/useWorkflowKeyboard.ts
index b7b4987f6..4298a6023 100644
--- a/src/workflow/panel/useWorkflowKeyboard.ts
+++ b/src/workflow/panel/useWorkflowKeyboard.ts
@@ -3,11 +3,15 @@ import { useInput } from '@anthropic/ink'
 /** 焦点所在列。 */
 export type FocusColumn = 'phases' | 'agents'
 
+/** 键盘模式：normal=正常导航；confirm=弹了 Dialog，等用户 y/n 确认。 */
+export type WorkflowKeyboardMode = 'normal' | 'confirm'
+
 /** useInput 的 key 对象子集（仅声明用到的字段，避免耦合 ink Key 类型）。 */
 type KeyEvent = {
   tab?: boolean
   shift?: boolean
   escape?: boolean
+  return?: boolean
   leftArrow?: boolean
   rightArrow?: boolean
   upArrow?: boolean
@@ -22,19 +26,34 @@ export type WorkflowKeyAction =
   | 'focusRight'
   | 'moveUp'
   | 'moveDown'
-  | 'kill'
+  | 'killAgent'
+  | 'killWorkflow'
   | 'resume'
   | 'newRun'
   | 'quit'
+  | 'confirmYes'
+  | 'confirmNo'
 
 export function routeWorkflowKey(
   input: string,
   key: KeyEvent,
+  mode: WorkflowKeyboardMode = 'normal',
 ): WorkflowKeyAction | null {
+  // confirm 模式：仅 y/Enter 确认，n/Esc/q 取消，其他键吞掉（防误触）
+  if (mode === 'confirm') {
+    if (input === 'y' || input === 'Y' || key.return) return 'confirmYes'
+    if (input === 'n' || input === 'N' || key.escape || input === 'q') {
+      return 'confirmNo'
+    }
+    return null
+  }
   // @anthropic/ink 的 key.tab 对 Tab 键置 true；个别环境回落到 '\t'
   if (key.tab || input === '\t') return key.shift ? 'prevTab' : 'nextTab'
   if (key.escape || input === 'q') return 'quit'
-  if (input === 'x') return 'kill'
+  // 大写 K = 杀整个 workflow；小写 x = 杀当前选中 agent（仅 agents 列）。
+  // 大小写区分避免 x 误触发 workflow kill；K 显式需要 Shift 暗示"重操作"。
+  if (input === 'K') return 'killWorkflow'
+  if (input === 'x') return 'killAgent'
   if (input === 'r') return 'resume'
   if (input === 'n') return 'newRun'
   if (key.leftArrow) return 'focusLeft'
@@ -52,10 +71,17 @@ export type WorkflowKeyboardHandlers = {
   focusRight: () => void
   moveUp: () => void
   moveDown: () => void
-  killFocused: () => void
+  /** 请求杀当前选中 agent（panel 弹 Dialog 二次确认）。 */
+  killAgent: () => void
+  /** 请求杀整个 workflow（panel 弹 Dialog 二次确认）。 */
+  killWorkflow: () => void
   resumeFocused: () => void
   newRun: () => void
   quit: () => void
+  /** confirm 模式下用户确认（y/Enter）。 */
+  confirmYes: () => void
+  /** confirm 模式下用户取消（n/Esc/q）。 */
+  confirmNo: () => void
 }
 
 /**
@@ -63,11 +89,16 @@ export type WorkflowKeyboardHandlers = {
  * - Tab / Shift+Tab：切顶部 run tab
  * - ← / →：phases ↔ agents 焦点切换
  * - ↑ / ↓：当前焦点列内移动
- * - x kill · r resume · n new · q / Esc quit
+ * - x kill 单 agent · K kill 整个 workflow（带 Dialog 二次确认） · r resume · n new · q / Esc quit
+ *
+ * @param mode confirm 时只接受 y/n/Esc/q，其他键吞掉——避免在确认弹窗里误导航。
  */
-export function useWorkflowKeyboard(h: WorkflowKeyboardHandlers): void {
+export function useWorkflowKeyboard(
+  h: WorkflowKeyboardHandlers,
+  mode: WorkflowKeyboardMode = 'normal',
+): void {
   useInput((input, key) => {
-    const action = routeWorkflowKey(input, key as KeyEvent)
+    const action = routeWorkflowKey(input, key as KeyEvent, mode)
     if (action === null) return
     switch (action) {
       case 'nextTab':
@@ -88,8 +119,11 @@ export function useWorkflowKeyboard(h: WorkflowKeyboardHandlers): void {
       case 'moveDown':
         h.moveDown()
         break
-      case 'kill':
-        h.killFocused()
+      case 'killAgent':
+        h.killAgent()
+        break
+      case 'killWorkflow':
+        h.killWorkflow()
         break
       case 'resume':
         h.resumeFocused()
@@ -100,6 +134,12 @@ export function useWorkflowKeyboard(h: WorkflowKeyboardHandlers): void {
       case 'quit':
         h.quit()
         break
+      case 'confirmYes':
+        h.confirmYes()
+        break
+      case 'confirmNo':
+        h.confirmNo()
+        break
     }
   })
 }
diff --git a/src/workflow/ports.ts b/src/workflow/ports.ts
index c6bb62299..bfeda9049 100644
--- a/src/workflow/ports.ts
+++ b/src/workflow/ports.ts
@@ -34,6 +34,8 @@ type RunBinding = {
   setAppState: SetAppState
   abortController: AbortController
   workflowName: string
+  /** agentId → AbortController。backend 启动 agent 时注册；killAgent 据此精确中断。 */
+  agentAbortControllers: Map<number, AbortController>
 }
 
 /** 每次工具调用从 toolUseContext 构造 WorkflowHostContext。 */
@@ -107,6 +109,7 @@ export function createWorkflowPorts(opts: {
         setAppState,
         abortController,
         workflowName: regOpts.workflowName,
+        agentAbortControllers: new Map(),
       })
       logForDebugging(
         `workflow task registered: ${runId} (${regOpts.workflowName})`,
@@ -131,8 +134,40 @@ export function createWorkflowPorts(opts: {
       const b = bindings.get(runId)
       if (!b) return
       killWorkflowTask(b.taskId, b.setAppState) // 内部 abort controller
+      // 杀 run 同时中断所有 in-flight agent（防止 backend 没接到 task abort 的极端时序）
+      for (const ac of b.agentAbortControllers.values()) {
+        try {
+          ac.abort()
+        } catch {
+          // no-op：abort 内部不会抛，但 fail-closed
+        }
+      }
+      b.agentAbortControllers.clear()
       bindings.delete(runId)
     },
+    registerAgentAbort(runId, agentId, ac) {
+      const b = bindings.get(runId)
+      if (!b) return
+      b.agentAbortControllers.set(agentId, ac)
+    },
+    unregisterAgentAbort(runId, agentId) {
+      const b = bindings.get(runId)
+      if (!b) return
+      b.agentAbortControllers.delete(agentId)
+    },
+    killAgent(runId, agentId) {
+      const b = bindings.get(runId)
+      if (!b) return false
+      const ac = b.agentAbortControllers.get(agentId)
+      if (!ac) return false
+      try {
+        ac.abort()
+      } catch {
+        // no-op
+      }
+      b.agentAbortControllers.delete(agentId)
+      return true
+    },
     pendingAction() {
       return null // v1：skip/retry 不接线（seam 保留）
     },
diff --git a/src/workflow/service.ts b/src/workflow/service.ts
index 4d4e09dfb..3e473dd7d 100644
--- a/src/workflow/service.ts
+++ b/src/workflow/service.ts
@@ -59,6 +59,11 @@ export type WorkflowService = {
     canUseTool: CanUseToolFn,
   ): Promise<{ runId: string; scriptPath?: string }>
   kill(runId: string): void
+  /**
+   * 中断单个 agent（不影响同 run 其他 agent，workflow 继续跑）。
+   * 返回是否命中（false = agent 已完成/不存在）。agent 被 abort 后返回 dead → null。
+   */
+  killAgent(runId: string, agentId: number): boolean
   /**
    * 进程退出 / 配置卸载时清理：杀掉所有 running run，避免孤儿 task。
    * 已完成/失败的 run 不受影响。幂等——多次调用安全。
@@ -243,6 +248,9 @@ export function makeService(
     kill(runId) {
       ports.taskRegistrar.kill(runId)
     },
+    killAgent(runId, agentId) {
+      return ports.taskRegistrar.killAgent?.(runId, agentId) ?? false
+    },
 
     shutdown() {
       // 仅杀 running：已完成/失败的 run taskRegistrar 已回收 binding，kill 是 no-op。