diff --git a/ShadowsocksX-NG2/App/ProxyRuntimeController+Commands.swift b/ShadowsocksX-NG2/App/ProxyRuntimeController+Commands.swift
index 8118ac7d..ff262db3 100644
--- a/ShadowsocksX-NG2/App/ProxyRuntimeController+Commands.swift
+++ b/ShadowsocksX-NG2/App/ProxyRuntimeController+Commands.swift
@@ -69,10 +69,11 @@ extension ProxyRuntimeController {
     } else {
       let cleanupOutcome = await cascadeSystemProxyOffForAgentOff()
       await stopAgent()
-      if let cleanupOutcome, cleanupOutcome.hasOperationFailure {
-        systemProxyObserver.systemProxyState = cleanupOutcome
+      if let cleanupOutcome {
+        systemProxyObserver.presentCleanupOutcome(cleanupOutcome)
+      } else {
+        systemProxyObserver.updateSystemProxyActions()
       }
-      systemProxyObserver.updateSystemProxyActions()
     }
   }
 
@@ -104,47 +105,24 @@ extension ProxyRuntimeController {
     guard persistSettings(next) else { return }
     settings = next
     if enabled {
-      systemProxyObserver.systemProxyInitialApplyPending = true
-      systemProxyObserver.systemProxyWasUnavailable = false
-      await systemProxyObserver.convergeSystemProxy()
-      systemProxyObserver.startEnabledSystemProxyObservation()
+      await systemProxyObserver.enableSystemProxyIntent()
     } else {
-      systemProxyObserver.systemProxyApprovalRequired = false
-      systemProxyObserver.systemProxyInitialApplyPending = false
-      systemProxyObserver.systemProxyReadGeneration += 1
-      systemProxyObserver.systemProxyState =
-        await systemProxyObserver.clearAndStopSystemProxyObservation()
-      systemProxyObserver.updateSystemProxyActions()
+      await systemProxyObserver.disableSystemProxyIntent()
     }
   }
 
   /// GUI startup restores the Agent. Healthy proxy intent only inspects; unhealthy
   /// proxy intent suspends; disabled intent never writes SystemConfiguration.
   func resyncOnLaunch() async {
-    systemProxyObserver.systemProxyStartupInProgress = true
+    systemProxyObserver.beginStartupResync()
     guard settings.agentEnabled else {
       await stopAgent()
-      systemProxyObserver.systemProxyStartupInProgress = false
-      if settings.systemProxyEnabled {
-        await systemProxyObserver.suspendSystemProxy()
-        systemProxyObserver.startEnabledSystemProxyObservation()
-      }
+      await systemProxyObserver.settleLaunchWithAgentOff()
       return
     }
     let catalog = catalogSnapshotReader.catalogSnapshot
     await convergeToReexpanded(catalog)
-    systemProxyObserver.systemProxyStartupInProgress = false
-    if settings.systemProxyEnabled {
-      systemProxyObserver.lastDesiredSystemProxyConfiguration = desiredSystemProxyConfiguration
-      if systemProxyExitAvailable {
-        await systemProxyObserver.recheckSystemProxy()
-      } else {
-        await systemProxyObserver.suspendSystemProxy()
-      }
-      systemProxyObserver.startEnabledSystemProxyObservation()
-    } else {
-      systemProxyObserver.systemProxyState = .idle
-    }
+    await systemProxyObserver.settleLaunchAfterAgentConverged()
   }
 
   // MARK: - 动作执行
@@ -159,23 +137,12 @@ extension ProxyRuntimeController {
   /// 系统代理状态按意图事实收尾——级联后意图已关闭为空闲；残留的「意图开
   /// 启 + agent 关闭」组合保持待应用（不静默清理，也无需网络观察）。
   func stopAgent() async {
-    systemProxyNetworkChangeMonitor.stop()
-    systemProxyObserver.systemProxyHealthTask?.cancel()
-    systemProxyObserver.systemProxyHealthTask = nil
-    systemProxyObserver.systemProxyObservationMode = .stopped
+    systemProxyObserver.agentDidStop()
     _ = await execute(.stop, document: nil)
     state = .off
     lastDocument = nil
     skippedServers = []
     lastActivationFailure = nil
-    if settings.systemProxyEnabled {
-      systemProxyObserver.systemProxyState = .pending
-    } else {
-      if !systemProxyState.hasOperationFailure {
-        systemProxyObserver.systemProxyState = .idle
-      }
-      systemProxyObserver.updateSystemProxyActions()
-    }
   }
 
   /// 无活动目标时 agent 仍提供本地监听（issue #60）：空服务器列表文档，
diff --git a/ShadowsocksX-NG2/App/ProxyRuntimeController+Mode.swift b/ShadowsocksX-NG2/App/ProxyRuntimeController+Mode.swift
index c4e5710a..33e8337d 100644
--- a/ShadowsocksX-NG2/App/ProxyRuntimeController+Mode.swift
+++ b/ShadowsocksX-NG2/App/ProxyRuntimeController+Mode.swift
@@ -50,7 +50,7 @@ extension ProxyRuntimeController {
     guard settings.agentEnabled, state != .off,
       let currentDocument = lastDocument ?? runtimeFileStore.loadDocument()
     else {
-      if settings.systemProxyEnabled { systemProxyObserver.systemProxyState = .pending }
+      systemProxyObserver.modeTransitionAwaitingRuntime()
       return
     }
 
diff --git a/ShadowsocksX-NG2/App/SystemProxyObserver.swift b/ShadowsocksX-NG2/App/SystemProxyObserver.swift
index adb61662..1e801b0f 100644
--- a/ShadowsocksX-NG2/App/SystemProxyObserver.swift
+++ b/ShadowsocksX-NG2/App/SystemProxyObserver.swift
@@ -14,23 +14,30 @@ final class SystemProxyObserver: ObservableObject {
   }
 
   /// Current configuration or operation result, independent of persisted intent.
-  @Published var systemProxyState: SystemProxyApplicationFacts = .idle
+  @Published private(set) var systemProxyState: SystemProxyApplicationFacts = .idle
   /// Approval remains actionable even after an off-intent clear failure.
-  @Published var systemProxyApprovalRequired = false
-  @Published var systemProxyInspection = SystemProxyInspectionFacts()
+  @Published private(set) var systemProxyApprovalRequired = false
+  @Published private(set) var systemProxyInspection = SystemProxyInspectionFacts()
 
-  var lastDesiredSystemProxyConfiguration: SystemProxyConfiguration?
-  var knownSystemProxyServices: Set<SystemProxyServiceIdentifier> = []
-  var systemProxyOperationInProgress = false
-  var systemProxyStartupInProgress = false
-  var systemProxyInitialApplyPending = false
-  var systemProxyWasUnavailable = false
+  // 写面唯一入口是下方「意图命令」；private(set) 的读面仅开给健康循环体
+  // 与观察机测试，其余实现细节一律 private。
+  private var lastDesiredSystemProxyConfiguration: SystemProxyConfiguration?
+  private var knownSystemProxyServices: Set<SystemProxyServiceIdentifier> = []
+  private var systemProxyOperationInProgress = false
+  /// 读面：健康循环体在 launch 重同步抑制期跳过巡检。
+  private(set) var systemProxyStartupInProgress = false
+  /// 读面：健康循环的收敛条件。
+  private(set) var systemProxyInitialApplyPending = false
+  /// 读面：健康循环的收敛条件。
+  private(set) var systemProxyWasUnavailable = false
+  /// 过渡：任务柄创建仍在控制器侧，柄归属收回观察机后转 private。
   var systemProxyHealthTask: Task<Void, Never>?
-  var systemProxyReadGeneration = 0
-  var systemProxyObservationMode = SystemProxyObservationMode.stopped
-  var systemProxyCleanupRescanRequested = false
-  var systemProxyCleanupTask: Task<SystemProxyApplicationFacts, Never>?
-  var systemProxyInspectionScheduled = false
+  private var systemProxyReadGeneration = 0
+  /// 读面：观察机测试。
+  private(set) var systemProxyObservationMode = SystemProxyObservationMode.stopped
+  private var systemProxyCleanupRescanRequested = false
+  private var systemProxyCleanupTask: Task<SystemProxyApplicationFacts, Never>?
+  private var systemProxyInspectionScheduled = false
 
   let systemProxy: SystemProxyControlling
   let systemProxyHelper: SystemProxyHelperServicing
@@ -216,28 +223,6 @@ final class SystemProxyObserver: ObservableObject {
     }
   }
 
-  func refreshSystemProxyApproval() {
-    systemProxyApprovalRequired =
-      systemProxyHelper.status != .approved
-      && (isIntentEnabled() || systemProxyState.hasOperationFailure)
-  }
-
-  func updateSystemProxyActions() {
-    refreshSystemProxyApproval()
-    let available = !systemProxyOperationInProgress && !systemProxyApprovalRequired
-    systemProxyInspection.canRepair =
-      available && isIntentEnabled()
-      && isExitAvailable() && systemProxyInspection.readFailure == nil
-      && (!systemProxyInspection.differences.isEmpty || systemProxyState.isApplyFailure)
-    systemProxyInspection.canRetryClear = available && systemProxyState.isClearFailure
-    if systemProxyState.hasOperationFailure {
-      startSystemProxyHealthObservation()
-    } else if !isIntentEnabled() {
-      systemProxyHealthTask?.cancel()
-      systemProxyHealthTask = nil
-    }
-  }
-
   func suspendSystemProxy() async {
     guard isIntentEnabled(), !systemProxyStartupInProgress else { return }
     guard !systemProxyWasUnavailable else {
@@ -296,6 +281,125 @@ final class SystemProxyObserver: ObservableObject {
   }
 }
 
+// MARK: - 呈现动作与批准刷新
+
+extension SystemProxyObserver {
+  func refreshSystemProxyApproval() {
+    systemProxyApprovalRequired =
+      systemProxyHelper.status != .approved
+      && (isIntentEnabled() || systemProxyState.hasOperationFailure)
+  }
+
+  func updateSystemProxyActions() {
+    refreshSystemProxyApproval()
+    let available = !systemProxyOperationInProgress && !systemProxyApprovalRequired
+    systemProxyInspection.canRepair =
+      available && isIntentEnabled()
+      && isExitAvailable() && systemProxyInspection.readFailure == nil
+      && (!systemProxyInspection.differences.isEmpty || systemProxyState.isApplyFailure)
+    systemProxyInspection.canRetryClear = available && systemProxyState.isClearFailure
+    if systemProxyState.hasOperationFailure {
+      startSystemProxyHealthObservation()
+    } else if !isIntentEnabled() {
+      systemProxyHealthTask?.cancel()
+      systemProxyHealthTask = nil
+    }
+  }
+}
+
+// MARK: - 意图命令（控制器写面唯一入口）
+
+extension SystemProxyObserver {
+  /// 系统代理意图开启（setSystemProxyEnabled on）：本轮必须真实应用一次——
+  /// 清理期可能已把系统设置清空，不能凭 lastDesired 相等跳过；收敛后转入
+  /// enabled 观察与网络变化巡检。
+  func enableSystemProxyIntent() async {
+    systemProxyInitialApplyPending = true
+    systemProxyWasUnavailable = false
+    await convergeSystemProxy()
+    startEnabledSystemProxyObservation()
+  }
+
+  /// 系统代理意图关闭（setSystemProxyEnabled off）：撤销待批准/待应用标记，
+  /// 读取代际推进作废在途读，无条件清理并停观察，结果原样呈现。
+  func disableSystemProxyIntent() async {
+    systemProxyApprovalRequired = false
+    systemProxyInitialApplyPending = false
+    systemProxyReadGeneration += 1
+    systemProxyState = await clearAndStopSystemProxyObservation()
+    updateSystemProxyActions()
+  }
+
+  /// agent 停机的观察收尾（stopAgent）：停网络监视与健康循环，观察模式归
+  /// 零。呈现按代理意图分流——意图仍在则保持待应用（等 agent 恢复后收敛，
+  /// issue #71），意图已关则空闲。
+  func agentDidStop() {
+    systemProxyNetworkChangeMonitor.stop()
+    systemProxyHealthTask?.cancel()
+    systemProxyHealthTask = nil
+    systemProxyObservationMode = .stopped
+    if isIntentEnabled() {
+      systemProxyState = .pending
+    } else {
+      if !systemProxyState.hasOperationFailure {
+        systemProxyState = .idle
+      }
+      updateSystemProxyActions()
+    }
+  }
+
+  /// agent 关闭级联的清理结果呈现（setAgentEnabled off）：typed 失败原样
+  /// 上屏（清理不重试），成功不覆盖既有呈现。
+  func presentCleanupOutcome(_ outcome: SystemProxyApplicationFacts) {
+    if outcome.hasOperationFailure {
+      systemProxyState = outcome
+    }
+    updateSystemProxyActions()
+  }
+
+  /// mode 切换发现无可收敛运行时（agent 关或无活动文档）：代理意图仍开时
+  /// 保持待应用，等运行时恢复后由健康循环收敛（+Mode 提前出口）。
+  func modeTransitionAwaitingRuntime() {
+    if isIntentEnabled() {
+      systemProxyState = .pending
+    }
+  }
+
+  /// launch 重同步开始（resyncOnLaunch 入口）：抑制期 converge/suspend 拒绝
+  /// 执行、健康循环跳过巡检；须由 settle 命令解除。
+  func beginStartupResync() {
+    systemProxyStartupInProgress = true
+  }
+
+  /// launch 重同步收尾（agent 意图关闭分支）：解除抑制（抑制期 suspend 的
+  /// 守卫会拒绝执行）；代理意图仍开则挂起残留配置并转入观察。
+  func settleLaunchWithAgentOff() async {
+    systemProxyStartupInProgress = false
+    if isIntentEnabled() {
+      await suspendSystemProxy()
+      startEnabledSystemProxyObservation()
+    }
+  }
+
+  /// launch 重同步收尾（agent 已收敛分支）：解除抑制；代理意图开则播种期望
+  /// 配置（健康 GUI 启动只巡检不强推应用），按出口可用性巡检或挂起，转入
+  /// 观察；意图关呈现空闲。
+  func settleLaunchAfterAgentConverged() async {
+    systemProxyStartupInProgress = false
+    if isIntentEnabled() {
+      lastDesiredSystemProxyConfiguration = desiredConfiguration()
+      if isExitAvailable() {
+        await recheckSystemProxy()
+      } else {
+        await suspendSystemProxy()
+      }
+      startEnabledSystemProxyObservation()
+    } else {
+      systemProxyState = .idle
+    }
+  }
+}
+
 // MARK: - helper 门禁（issue #71）
 
 extension SystemProxyObserver {
diff --git a/ShadowsocksX-NG2/Tests/SystemProxyObserverTests.swift b/ShadowsocksX-NG2/Tests/SystemProxyObserverTests.swift
index bd7adcde..b1612767 100644
--- a/ShadowsocksX-NG2/Tests/SystemProxyObserverTests.swift
+++ b/ShadowsocksX-NG2/Tests/SystemProxyObserverTests.swift
@@ -34,7 +34,6 @@ final class SystemProxyObserverTests: XCTestCase {
   func testConvergeWaitsForInFlightOperationInsteadOfSkipping() async throws {
     let proxy = ProxyRuntimeFixture.FakeSystemProxy()
     let observer = makeObserver(proxy: proxy, cleanupSettleNanoseconds: 1_000_000)
-    observer.systemProxyInitialApplyPending = true
     // 拉长首次读服务的窗口，制造进行中的操作。
     proxy.beforeRead = { _ = try? await Task.sleep(nanoseconds: 30_000_000) }
 
@@ -46,11 +45,101 @@ final class SystemProxyObserverTests: XCTestCase {
     XCTAssertEqual(proxy.applied.count, 2, "并发收敛必须等操作收尾后执行而非被跳过")
   }
 
+  func testEnableIntentAppliesFreshAndStartsObservation() async throws {
+    let proxy = ProxyRuntimeFixture.FakeSystemProxy()
+    let monitor = ProxyRuntimeFixture.FakeSystemProxyNetworkChangeMonitor()
+    let observer = makeObserver(proxy: proxy, monitor: monitor, cleanupSettleNanoseconds: 1_000_000)
+
+    await observer.enableSystemProxyIntent()
+
+    XCTAssertEqual(proxy.applied.count, 1, "开启意图必须真实应用一次（清理期可能已清空系统设置）")
+    XCTAssertEqual(observer.systemProxyState, .applied)
+    XCTAssertEqual(observer.systemProxyObservationMode, .enabled)
+    XCTAssertEqual(monitor.startCount, 1)
+  }
+
+  func testDisableIntentClearsStopsObservationAndPublishesOutcome() async throws {
+    let proxy = ProxyRuntimeFixture.FakeSystemProxy()
+    let monitor = ProxyRuntimeFixture.FakeSystemProxyNetworkChangeMonitor()
+    let observer = makeObserver(proxy: proxy, monitor: monitor, cleanupSettleNanoseconds: 1_000_000)
+    await observer.enableSystemProxyIntent()
+
+    await observer.disableSystemProxyIntent()
+
+    XCTAssertEqual(proxy.clearCount, 1)
+    XCTAssertEqual(observer.systemProxyState, .idle)
+    XCTAssertEqual(observer.systemProxyObservationMode, .stopped)
+    XCTAssertEqual(monitor.stopCount, 1)
+    XCTAssertFalse(observer.systemProxyApprovalRequired)
+  }
+
+  func testAgentStopPresentationFollowsProxyIntent() async throws {
+    let proxy = ProxyRuntimeFixture.FakeSystemProxy()
+    let monitor = ProxyRuntimeFixture.FakeSystemProxyNetworkChangeMonitor()
+    var intentEnabled = true
+    let observer = makeObserver(
+      proxy: proxy, monitor: monitor, cleanupSettleNanoseconds: 1_000_000,
+      isIntentEnabled: { intentEnabled })
+
+    observer.agentDidStop()
+    XCTAssertEqual(observer.systemProxyState, .pending, "代理意图仍在开时，agent 停机保持待应用（issue #71）")
+    XCTAssertEqual(observer.systemProxyObservationMode, .stopped)
+    XCTAssertEqual(monitor.stopCount, 1)
+
+    intentEnabled = false
+    observer.agentDidStop()
+    XCTAssertEqual(observer.systemProxyState, .idle, "代理意图已关时，agent 停机呈现空闲")
+  }
+
+  func testModeTransitionAwaitingRuntimeStampsPendingOnlyUnderIntent() async throws {
+    var intentEnabled = false
+    let observer = makeObserver(
+      proxy: ProxyRuntimeFixture.FakeSystemProxy(), cleanupSettleNanoseconds: 1_000_000,
+      isIntentEnabled: { intentEnabled })
+
+    observer.modeTransitionAwaitingRuntime()
+    XCTAssertEqual(observer.systemProxyState, .idle, "代理意图关闭时不打待应用图章")
+
+    intentEnabled = true
+    observer.modeTransitionAwaitingRuntime()
+    XCTAssertEqual(observer.systemProxyState, .pending)
+  }
+
+  func testSettleLaunchAfterConvergedInspectsWithoutReapplying() async throws {
+    let proxy = ProxyRuntimeFixture.FakeSystemProxy()
+    let observer = makeObserver(proxy: proxy, cleanupSettleNanoseconds: 1_000_000)
+
+    await observer.settleLaunchAfterAgentConverged()
+
+    XCTAssertEqual(proxy.applied.count, 0, "健康的 GUI 启动只巡检，不强推应用")
+    XCTAssertGreaterThanOrEqual(proxy.readCount, 1)
+    XCTAssertEqual(observer.systemProxyObservationMode, .enabled)
+    XCTAssertFalse(observer.systemProxyStartupInProgress)
+    // 播种 lastDesired 后，后续收敛（如网络变化回调）不得因相等而重新应用。
+    await observer.convergeSystemProxy()
+    XCTAssertEqual(proxy.applied.count, 0, "播种 lastDesired 后收敛不得重新应用")
+  }
+
+  func testStartupSuppressionBlocksConvergeUntilSettled() async throws {
+    let proxy = ProxyRuntimeFixture.FakeSystemProxy()
+    let observer = makeObserver(proxy: proxy, cleanupSettleNanoseconds: 1_000_000)
+    observer.beginStartupResync()
+
+    await observer.convergeSystemProxy(forceApply: true)
+    XCTAssertEqual(proxy.applied.count, 0, "launch 重同步抑制期 converge 必须被拒绝")
+
+    await observer.settleLaunchWithAgentOff()
+    XCTAssertFalse(observer.systemProxyStartupInProgress)
+    XCTAssertEqual(observer.systemProxyState, .paused, "抑制解除后按意图挂起残留配置")
+    XCTAssertEqual(observer.systemProxyObservationMode, .enabled)
+  }
+
   private func makeObserver(
     proxy: ProxyRuntimeFixture.FakeSystemProxy,
     monitor: SystemProxyNetworkChangeMonitoring =
       ProxyRuntimeFixture.FakeSystemProxyNetworkChangeMonitor(),
-    cleanupSettleNanoseconds: UInt64
+    cleanupSettleNanoseconds: UInt64,
+    isIntentEnabled: @escaping @MainActor () -> Bool = { true }
   ) -> SystemProxyObserver {
     SystemProxyObserver(
       systemProxy: proxy,
@@ -59,7 +148,7 @@ final class SystemProxyObserverTests: XCTestCase {
       appBundle: AppArtifact.bundle,
       helperRefreshDelayNanoseconds: 1_000_000,
       cleanupSettleNanoseconds: cleanupSettleNanoseconds,
-      isIntentEnabled: { true },
+      isIntentEnabled: isIntentEnabled,
       isExitAvailable: { true },
       desiredConfiguration: {
         try? ProxyMode.direct.systemProxyConfiguration(