feat: implement Monitor tool for streaming shell output

scripts/build.ts

@@ -24,7 +24,7 @@ const featureFlags: Record<string, boolean> = {
   BRIDGE_MODE: false,
   DAEMON: false,
   AGENT_TRIGGERS: false,
-  MONITOR_TOOL: false,
+  MONITOR_TOOL: true,
   ABLATION_BASELINE: false,
   DUMP_SYSTEM_PROMPT: false,
   CACHED_MICROCOMPACT: false,

src/components/permissions/MonitorPermissionRequest/MonitorPermissionRequest.tsx

@@ -0,0 +1,173 @@
+import React from 'react'
+import { getOriginalCwd } from '../../../bootstrap/state.js'
+import { Box, Text } from '../../../ink.js'
+import { sanitizeToolNameForAnalytics } from '../../../services/analytics/metadata.js'
+import { env } from '../../../utils/env.js'
+import { shouldShowAlwaysAllowOptions } from '../../../utils/permissions/permissionsLoader.js'
+import { usePermissionRequestLogging } from '../hooks.js'
+import { PermissionDialog } from '../PermissionDialog.js'
+import {
+  PermissionPrompt,
+  type PermissionPromptOption,
+} from '../PermissionPrompt.js'
+import type { PermissionRequestProps } from '../PermissionRequest.js'
+import { PermissionRuleExplanation } from '../PermissionRuleExplanation.js'
+import { logUnaryPermissionEvent } from '../utils.js'
+
+type OptionValue = 'yes' | 'yes-dont-ask-again' | 'no'
+
+export function MonitorPermissionRequest({
+  toolUseConfirm,
+  onDone,
+  onReject,
+  workerBadge,
+}: PermissionRequestProps) {
+  const { command, description } = toolUseConfirm.input as {
+    command?: string
+    description?: string
+  }
+
+  usePermissionRequestLogging(toolUseConfirm, {
+    completion_type: 'tool_use_single',
+    language_name: 'none',
+  })
+
+  const handleSelect = (
+    value: OptionValue,
+    feedback?: string,
+  ) => {
+    switch (value) {
+      case 'yes': {
+        logUnaryPermissionEvent({
+          completion_type: 'tool_use_single',
+          event: 'accept',
+          metadata: {
+            language_name: 'none',
+            message_id: toolUseConfirm.assistantMessage.message.id,
+            platform: env.platform,
+          },
+        })
+        toolUseConfirm.onAllow(toolUseConfirm.input, [], feedback)
+        onDone()
+        break
+      }
+      case 'yes-dont-ask-again': {
+        logUnaryPermissionEvent({
+          completion_type: 'tool_use_single',
+          event: 'accept',
+          metadata: {
+            language_name: 'none',
+            message_id: toolUseConfirm.assistantMessage.message.id,
+            platform: env.platform,
+          },
+        })
+        // Save the rule under 'Bash' toolName because checkPermissions
+        // delegates to bashToolHasPermission which matches rules against
+        // BashTool. Using 'Monitor' here would create a rule that's never
+        // checked. Command-specific prefix (like BashTool's shellRuleMatching).
+        const cmdForRule = command?.trim() || ''
+        const prefix = cmdForRule.split(/\s+/).slice(0, 2).join(' ')
+        toolUseConfirm.onAllow(toolUseConfirm.input, prefix ? [
+          {
+            type: 'addRules',
+            rules: [{ toolName: 'Bash', ruleContent: `${prefix}:*` }],
+            behavior: 'allow',
+            destination: 'localSettings',
+          },
+        ] : [])
+        onDone()
+        break
+      }
+      case 'no': {
+        logUnaryPermissionEvent({
+          completion_type: 'tool_use_single',
+          event: 'reject',
+          metadata: {
+            language_name: 'none',
+            message_id: toolUseConfirm.assistantMessage.message.id,
+            platform: env.platform,
+          },
+        })
+        toolUseConfirm.onReject(feedback)
+        onReject()
+        onDone()
+        break
+      }
+    }
+  }
+
+  const handleCancel = () => {
+    logUnaryPermissionEvent({
+      completion_type: 'tool_use_single',
+      event: 'reject',
+      metadata: {
+        language_name: 'none',
+        message_id: toolUseConfirm.assistantMessage.message.id,
+        platform: env.platform,
+      },
+    })
+    toolUseConfirm.onReject()
+    onReject()
+    onDone()
+  }
+
+  const showAlwaysAllow = shouldShowAlwaysAllowOptions()
+  const originalCwd = getOriginalCwd()
+
+  const options: PermissionPromptOption<OptionValue>[] = [
+    {
+      label: 'Yes',
+      value: 'yes',
+      feedbackConfig: { type: 'accept' },
+    },
+  ]
+
+  if (showAlwaysAllow) {
+    options.push({
+      label: (
+        <Text>
+          Yes, and don&apos;t ask again for{' '}
+          <Text bold>Monitor</Text> commands in{' '}
+          <Text bold>{originalCwd}</Text>
+        </Text>
+      ),
+      value: 'yes-dont-ask-again',
+    })
+  }
+
+  options.push({
+    label: 'No',
+    value: 'no',
+    feedbackConfig: { type: 'reject' },
+  })
+
+  const toolAnalyticsContext = {
+    toolName: sanitizeToolNameForAnalytics(toolUseConfirm.tool.name),
+    isMcp: toolUseConfirm.tool.isMcp ?? false,
+  }
+
+  return (
+    <PermissionDialog title="Monitor" workerBadge={workerBadge}>
+      <Box flexDirection="column" paddingX={2} paddingY={1}>
+        <Text>
+          Monitor({command ?? ''})
+        </Text>
+        {description ? (
+          <Text dimColor>{description}</Text>
+        ) : null}
+      </Box>
+      <Box flexDirection="column">
+        <PermissionRuleExplanation
+          permissionResult={toolUseConfirm.permissionResult}
+          toolType="tool"
+        />
+        <PermissionPrompt
+          options={options}
+          onSelect={handleSelect}
+          onCancel={handleCancel}
+          toolAnalyticsContext={toolAnalyticsContext}
+        />
+      </Box>
+    </PermissionDialog>
+  )
+}

src/tasks/MonitorMcpTask/MonitorMcpTask.ts

@@ -0,0 +1,102 @@
+// MonitorMcpTask — task registry entry for the 'monitor_mcp' type.
+//
+// Architecture: MonitorTool spawns shell processes as LocalShellTask
+// (type: 'local_bash', kind: 'monitor'). The 'monitor_mcp' type exists
+// in TaskType for forward-compatibility with MCP-based monitoring (not
+// yet implemented). This module satisfies the import from tasks.ts and
+// provides killMonitorMcpTasksForAgent for agent-scoped cleanup of
+// monitor-kind shell tasks.
+
+import type { AppState } from '../../state/AppState.js'
+import type { SetAppState, Task, TaskStateBase } from '../../Task.js'
+import type { AgentId } from '../../types/ids.js'
+import { logForDebugging } from '../../utils/debug.js'
+import { dequeueAllMatching } from '../../utils/messageQueueManager.js'
+import { evictTaskOutput } from '../../utils/task/diskOutput.js'
+import { updateTaskState } from '../../utils/task/framework.js'
+import { isLocalShellTask } from '../LocalShellTask/guards.js'
+import { killTask } from '../LocalShellTask/killShellTasks.js'
+
+export type MonitorMcpTaskState = TaskStateBase & {
+  type: 'monitor_mcp'
+  agentId?: AgentId
+}
+
+function isMonitorMcpTask(task: unknown): task is MonitorMcpTaskState {
+  return (
+    typeof task === 'object' &&
+    task !== null &&
+    'type' in task &&
+    task.type === 'monitor_mcp'
+  )
+}
+
+export const MonitorMcpTask: Task = {
+  name: 'MonitorMcpTask',
+  type: 'monitor_mcp',
+  async kill(taskId, setAppState) {
+    updateTaskState<MonitorMcpTaskState>(taskId, setAppState, task => {
+      if (task.status !== 'running') {
+        return task
+      }
+
+      return {
+        ...task,
+        status: 'killed',
+        notified: true,
+        endTime: Date.now(),
+      }
+    })
+    void evictTaskOutput(taskId)
+  },
+}
+
+/**
+ * Kill all monitor tasks owned by a given agent.
+ *
+ * MonitorTool spawns tasks as local_bash with kind='monitor'. When an agent
+ * exits, killShellTasksForAgent already handles those. This function provides
+ * additional cleanup for any monitor_mcp-typed tasks and also kills any
+ * local_bash tasks with kind='monitor' that might have been missed (belt and
+ * suspenders). Finally, it purges queued notifications for the dead agent.
+ */
+export function killMonitorMcpTasksForAgent(
+  agentId: AgentId,
+  getAppState: () => AppState,
+  setAppState: SetAppState,
+): void {
+  const tasks = getAppState().tasks ?? {}
+
+  for (const [taskId, task] of Object.entries(tasks)) {
+    // Kill monitor_mcp tasks for this agent
+    if (
+      isMonitorMcpTask(task) &&
+      task.agentId === agentId &&
+      task.status === 'running'
+    ) {
+      logForDebugging(
+        `killMonitorMcpTasksForAgent: killing monitor_mcp task ${taskId} (agent ${agentId} exiting)`,
+      )
+      void MonitorMcpTask.kill(taskId, setAppState)
+    }
+
+    // Also kill local_bash tasks with kind='monitor' for this agent
+    // (killShellTasksForAgent already does this, but being explicit
+    // guards against ordering issues)
+    if (
+      isLocalShellTask(task) &&
+      task.kind === 'monitor' &&
+      task.agentId === agentId &&
+      task.status === 'running'
+    ) {
+      logForDebugging(
+        `killMonitorMcpTasksForAgent: killing monitor shell task ${taskId} (agent ${agentId} exiting)`,
+      )
+      killTask(taskId, setAppState)
+    }
+  }
+
+  // Purge any queued notifications addressed to this agent — its query loop
+  // has exited and won't drain them.
+  dequeueAllMatching(cmd => cmd.agentId === agentId)
+}