Claude Code v2.1.88 Custom React Hooks System - Deep-Dive Analysis

Document Version: 1.0 Generated: 2026-04-02 Scope: 104 custom hooks across 19,204 lines of code Focus: Architecture, state patterns, dependency chains, design decisions

Executive Summary
Hook Architecture Overview
The Typeahead Suggestion Engine (1,384 lines)
File Suggestion System with Native Rust Integration
Voice Pipeline Architecture
Team/Swarm Hooks
Remote Session Management
Permission State Machine
Notification System
State Patterns & AppState Integration
Hook Dependency Chains
Complete Hook Catalog
Key Constants & Timeouts
Security Considerations

Executive Summary

Claude Code v2.1.88 implements a sophisticated modular hook architecture with 104 custom React hooks organized into 8 primary domains:

Input & Suggestions (useTypeahead, fileSuggestions, unifiedSuggestions) - Unified command/file/history/Slack suggestion engine
Voice I/O (useVoice, useVoiceIntegration) - Hold-to-talk STT via Anthropic voice_stream endpoint
Team/Swarm (useInboxPoller, useSwarmPermissionPoller) - Distributed agent coordination and permission brokering
Remote Sessions (useReplBridge, useRemoteSession) - Always-on claude.ai bridge and CCR WebSocket adapter
Permissions (toolPermission/ directory) - Hierarchical permission state machine with classifier integration
Notifications (notifs/ subdirectory, 16 hooks) - Context-aware lifecycle management
Text Input (useTextInput, useVimInput, useSearchInput, useArrowKeyHistory) - Multi-mode editor with emacs/vim keybindings
Utilities (40+ small hooks) - Keybindings, task watching, IDE integration, diff rendering

The system exhibits sophisticated patterns for:

Lazy loading (voice module deferred until activation)
Singleton state (FileIndex, TasksV2Store)
External store subscription (useSyncExternalStore across hooks)
Async initialization (Promise-backed background index rebuilds)
Cross-context async execution (AsyncLocalStorage for teammate context)
Permission hierarchies (user→classifier→hook→swarm worker→team lead)

Total lines analyzed: ~19,204 across all hooks, 811 in fileSuggestions alone, 1,384 in useTypeahead.

Hook Architecture Overview

Domain Categories & Decomposition

The 104 hooks decompose the application along these axes:

INPUT LAYER (27 hooks)
├─ Text Input
│  ├─ useTextInput.ts (529 lines)          - Core editor with multi-mode support
│  ├─ useVimInput.ts (316 lines)           - Vim keybinding layer
│  ├─ useSearchInput.ts (364 lines)        - History search with vim keys
│  ├─ useArrowKeyHistory.tsx (228 lines)   - Arrow-key history navigation
│  └─ useInputBuffer.ts (132 lines)        - Input buffering/flow control
├─ Suggestions
│  ├─ useTypeahead.tsx (1,384 lines)       - [PRIMARY] Unified suggestion engine
│  ├─ fileSuggestions.ts (811 lines)       - File indexing + git tracking
│  ├─ unifiedSuggestions.ts (202 lines)    - Fuse.js scoring/merging
│  └─ usePromptSuggestion.ts (177 lines)   - Model-based suggestions
├─ Keybindings & Navigation
│  ├─ useCommandKeybindings.tsx (107 lines) - Command palette keybindings
│  ├─ useGlobalKeybindings.tsx (248 lines)  - Global shortcut dispatcher
│  └─ useHistorySearch.ts (303 lines)       - Search history + scoring
└─ Special Input Modes
   ├─ usePasteHandler.ts (285 lines)       - Rich paste (images, URLs)
   ├─ useCopyOnSelect.ts (98 lines)        - Selection-triggered copy
   └─ useClipboardImageHint.ts (77 lines)  - Clipboard mode hint

VOICE LAYER (2 hooks)
├─ useVoice.ts (1,144 lines)               - [CORE] Hold-to-talk STT
└─ useVoiceIntegration.tsx (676 lines)     - Voice UI dispatcher

TEAM/SWARM LAYER (7 hooks)
├─ useInboxPoller.ts (969 lines)           - [CORE] Mailbox polling
├─ useSwarmPermissionPoller.ts (330 lines) - Permission response polling
├─ useSwarmInitialization.ts (81 lines)    - Team context setup
├─ useTeammateViewAutoExit.ts (63 lines)   - Teammate session teardown
├─ useSessionBackgrounding.ts (158 lines)  - Session focus/blur handling
├─ useAwaySummary.ts (125 lines)           - Away message generation
└─ useMailboxBridge.ts (21 lines)          - Mailbox file bridge

REMOTE SESSION LAYER (2 hooks)
├─ useReplBridge.tsx (722 lines)           - [CORE] Always-on claude.ai bridge
└─ useRemoteSession.ts (605 lines)         - CCR WebSocket + SDK adapter

PERMISSION LAYER (5 files, 1,386 LOC total)
├─ toolPermission/
│  ├─ PermissionContext.ts (388 lines)     - Permission state machine
│  ├─ handlers/
│  │  ├─ interactiveHandler.ts (536 lines) - User prompt + feedback
│  │  ├─ swarmWorkerHandler.ts (159 lines) - Worker-side async flow
│  │  └─ coordinatorHandler.ts (65 lines)  - Coordinator side
│  ├─ permissionLogging.ts (238 lines)     - Decision analytics
│  └─ useCanUseTool.tsx (203 lines)        - [HOOK] Permission gating

NOTIFICATION LAYER (16 hooks, 1,342 LOC total)
├─ notifs/
│  ├─ useFastModeNotification.tsx (161 lines)
│  ├─ useIDEStatusIndicator.tsx (185 lines)
│  ├─ useLspInitializationNotification.tsx (142 lines)
│  ├─ useMcpConnectivityStatus.tsx (87 lines)
│  ├─ useRateLimitWarningNotification.tsx (113 lines)
│  ├─ usePluginInstallationStatus.tsx (127 lines)
│  ├─ useDeprecationWarningNotification.tsx (43 lines)
│  ├─ useCanSwitchToExistingSubscription.tsx (59 lines)
│  ├─ usePluginAutoupdateNotification.tsx (82 lines)
│  ├─ useModelMigrationNotifications.tsx (51 lines)
│  ├─ useTeammateShutdownNotification.ts (78 lines)
│  ├─ useAutoModeUnavailableNotification.ts (56 lines)
│  ├─ useSettingsErrors.tsx (68 lines)
│  ├─ useOfficialMarketplaceNotification.tsx (47 lines)
│  ├─ useInstallMessages.tsx (25 lines)
│  ├─ useStartupNotification.ts (41 lines)
│  ├─ useNpmDeprecationNotification.ts (24 lines)
│  └─ (custom notification context integration)

TASK & PERSISTENCE LAYER (5 hooks)
├─ useTasksV2.ts (250 lines)               - TodoV2 file watcher (singleton)
├─ useTaskListWatcher.ts (221 lines)       - Background task file sync
├─ useScheduledTasks.ts (139 lines)        - Scheduled task polling
├─ useBackgroundTaskNavigation.ts (251 lines) - Task execution routing
└─ useFileHistorySnapshotInit.ts (25 lines) - Session file history

IDE & TOOL INTEGRATION (7 hooks)
├─ useIDEIntegration.tsx (69 lines)        - IDE connection bridge
├─ useIdeSelection.ts (150 lines)          - Selection sync
├─ useIdeAtMentioned.ts (76 lines)         - @mention → IDE
├─ useIdeLogging.ts (41 lines)             - IDE activity logging
├─ useIdeConnectionStatus.ts (33 lines)    - Status checks
├─ useDiffInIDE.ts (379 lines)             - Diff viewport management
└─ useTurnDiffs.ts (213 lines)             - Turn-scoped diff tracking

DIFF & DISPLAY (3 hooks)
├─ useDiffInIDE.ts (379 lines)             - Diff layout/scrolling
├─ useDiffData.ts (110 lines)              - Diff state machine
├─ useVirtualScroll.ts (721 lines)         - Performant list rendering

LSP & PLUGIN SYSTEM (4 hooks)
├─ useLspPluginRecommendation.tsx (193 lines) - LSP plugin suggestions
├─ usePluginRecommendationBase.tsx (104 lines) - Plugin discovery base
├─ useManagePlugins.ts (304 lines)        - Plugin lifecycle
└─ usePromptsFromClaudeInChrome.tsx (70 lines) - Browser extension bridge

SESSION & LIFECYCLE (8 hooks)
├─ useExitOnCtrlCD.ts (95 lines)           - Session shutdown signal
├─ useExitOnCtrlCDWithKeybindings.ts (24 lines) - Keybinding variant
├─ useSessionBackgrounding.ts (158 lines)  - Focus/blur events
├─ useTeleportResume.tsx (84 lines)        - Session state restore
├─ useLogMessages.ts (119 lines)           - Message persistence
├─ useAssistantHistory.ts (250 lines)      - Conversation history
├─ useCanUseTool.tsx (203 lines)           - Tool availability checks
└─ useCancelRequest.ts (276 lines)         - Request abortion

UTILITY LAYER (20+ small hooks <100 LOC)
├─ Keybindings & Input
│  ├─ useDoublePress.ts (62 lines)         - Double-press detection
│  ├─ useCommandQueue.ts (15 lines)        - Command queuing
│  └─ useInputBuffer.ts (132 lines)        - Input buffering
├─ SSH & Terminal
│  ├─ useSSHSession.ts (241 lines)         - SSH backend bridge
│  ├─ useDirectConnect.ts (229 lines)      - Direct connection
│  ├─ useTerminalSize.ts (15 lines)        - Terminal dimensions
│  └─ useExitOnCtrlCD.ts (95 lines)        - Session exit
├─ State & Rendering
│  ├─ useBlink.ts (34 lines)               - Cursor blink animation
│  ├─ useMinDisplayTime.ts (35 lines)      - Debounce display updates
│  ├─ useElapsedTime.ts (37 lines)         - Time delta calculation
│  └─ useMemoryUsage.ts (39 lines)         - Memory monitoring
├─ Async Patterns
│  ├─ useQueueProcessor.ts (68 lines)      - Queue drain pattern
│  ├─ useNotifyAfterTimeout.ts (65 lines)  - Delayed notification
│  └─ useTimeout.ts (14 lines)             - Simple timer
├─ Hooks & Callbacks
│  ├─ useAfterFirstRender.ts (17 lines)    - Post-mount guard
│  ├─ useDeferredHookMessages.ts (46 lines) - Deferred message queue
│  └─ useLogMessages.ts (119 lines)        - Message logging
├─ Config & Settings
│  ├─ useSettings.ts (17 lines)            - Settings context access
│  ├─ useSettingsChange.ts (25 lines)      - Settings change listener
│  ├─ useDynamicConfig.ts (22 lines)       - Dynamic config loader
│  └─ useApiKeyVerification.ts (84 lines)  - API credential check
├─ Platform & Features
│  ├─ useVoiceEnabled.ts (25 lines)        - Voice feature check
│  ├─ usePrStatus.ts (106 lines)           - PR tracking
│  ├─ useUpdateNotification.ts (34 lines)  - Update prompts
│  └─ useMainLoopModel.ts (34 lines)       - Model selection
├─ Error & Debugging
│  ├─ useIssueFlagBanner.ts (133 lines)    - Issue reporting UI
│  └─ useClaudeCodeHintRecommendation.tsx (128 lines) - Feature hints
├─ Recommendation System
│  ├─ useSkillImprovementSurvey.ts (105 lines) - Skill feedback
│  ├─ useSkillsChange.ts (62 lines)        - Skill change tracking
│  ├─ useLspPluginRecommendation.tsx (193 lines) - LSP recommendations
│  └─ useOfficialMarketplaceNotification.tsx (47 lines)
├─ Custom Chrome Extension
│  └─ useChromeExtensionNotification.tsx (49 lines) - Extension bridge
└─ Misc Utilities
   ├─ useMergedClients.ts (23 lines)       - Client merging
   ├─ useMergedCommands.ts (15 lines)      - Command merging
   ├─ useMergedTools.ts (44 lines)         - Tool merging
   └─ renderPlaceholder.ts (51 lines)      - Placeholder rendering

Architecture Principles

Separation of Concerns: Each hook handles a single aspect (input, voice, permissions, etc.)
Singleton Patterns: FileIndex, TasksV2Store persist across re-renders
Lazy Loading: Voice module deferred until user activates hold-to-talk
External Store Subscriptions: AppState accessed via useSyncExternalStore for fine-grained updates
Promise-Based Async: Background operations (index rebuild, git ls-files) backed by Promises
Event Sourcing: Permission decisions logged with full context for auditing
Async Context Propagation: AsyncLocalStorage for teammate/swarm context across async boundaries

The Typeahead Suggestion Engine

File: `useTypeahead.tsx` (1,384 lines)

The centerpiece of Claude Code's intelligent suggestion system. Merges five suggestion sources into a single ranked list with context-aware filtering, debouncing, and keyboard navigation.

Architecture

useTypeahead.tsx (hook)
├─ Input Processing
│  ├─ extractCompletionToken() - Unicode-aware token extraction
│  ├─ extractSearchToken() - Remove @/quotes from tokens
│  └─ formatReplacementValue() - Apply @ prefix + quoting
├─ Suggestion Generation (async, debounced)
│  ├─ Command Suggestions
│  │  ├─ isCommandInput() - /slash command detection
│  │  ├─ generateCommandSuggestions() - Command matching
│  │  ├─ generateProgressiveArgumentHint() - Argument help text
│  │  └─ findMidInputSlashCommand() - Incomplete command detection
│  ├─ File Suggestions
│  │  ├─ fileSuggestions.ts (811 lines) - [IMPORTED]
│  │  └─ applyFileSuggestion() - Token replacement logic
│  ├─ Directory Completions
│  │  ├─ getDirectoryCompletions() - Path traversal
│  │  ├─ getPathCompletions() - Relative path resolution
│  │  ├─ isPathLikeToken() - Path detection regex
│  │  └─ applyDirectorySuggestion() - Path token replacement
│  ├─ Shell Completions
│  │  ├─ getShellCompletions() - bash/zsh completion
│  │  ├─ generateBashSuggestions() - Async shell spawning (AbortController)
│  │  └─ applyShellSuggestion() - Shell token replacement
│  ├─ Slack Channel Completions
│  │  ├─ getSlackChannelSuggestions() - #channel matching
│  │  ├─ hasSlackMcpServer() - MCP server detection
│  │  └─ applyTriggerSuggestion() - Trigger-based replacement
│  ├─ Session History
│  │  ├─ searchSessionsByCustomTitle() - Session lookup
│  │  └─ getSessionIdFromLog() - Session ID extraction
│  ├─ Unified Merging
│  │  └─ generateUnifiedSuggestions() - Fuse.js + file scoring
│  └─ Auto-Approval (hooks)
│     └─ executePermissionRequestHooks() - [HOOK] Pre-filtering
├─ Keyboard Navigation
│  ├─ handleKeyDown(event) - Dispatcher
│  ├─ Up/Down Arrow - Selection cycling
│  ├─ Tab - Completion acceptance
│  ├─ Escape - Dismissal
│  └─ Enter - Submission (conditional)
├─ Suggestion Selection Preservation
│  └─ getPreservedSelection() - Maintain selection across updates
└─ Props
   ├─ input: string - Current input text
   ├─ cursorOffset: number - Cursor position
   ├─ commands: Command[] - Available slash commands
   ├─ agents: AgentDefinition[] - Available agents
   ├─ suggestionsState - Current UI state
   ├─ onInputChange - Update input value
   ├─ onSubmit - Finalize input
   ├─ setCursorOffset - Update cursor
   ├─ suppressSuggestions? - Disable UI rendering
   └─ onModeChange? - Prompt mode transition

Regex Patterns (Unicode-Aware)

// File path tokens: includes CJK, Latin, Cyrillic, combining marks
AT_TOKEN_HEAD_RE = /^@[\p{L}\p{N}\p{M}_\-./\\()[\]~:]*/u
PATH_CHAR_HEAD_RE = /^[\p{L}\p{N}\p{M}_\-./\\()[\]~:]+/u
TOKEN_WITH_AT_RE = /(@[\p{L}\p{N}\p{M}_\-./\\()[\]~:]*|[\p{L}\p{N}\p{M}_\-./\\()[\]~:]+)$/u
TOKEN_WITHOUT_AT_RE = /[\p{L}\p{N}\p{M}_\-./\\()[\]~:]+$/u
HAS_AT_SYMBOL_RE = /(^|\s)@([\p{L}\p{N}\p{M}_\-./\\()[\]~:]*|"[^"]*"?)$/u

// Slack: only ASCII-lowercase channels
HASH_CHANNEL_RE = /(^|\s)#([a-z0-9][a-z0-9_-]*)$/

Suggestion Type Hierarchy

type SuggestionItem = {
  id: string                          // Unique identifier
  displayText: string                 // User-facing label
  description?: string                // Help text
  metadata?: unknown                  // Type-specific data
  color?: keyof Theme                 // Optional coloring
}

type SuggestionType =
  | 'command'                         // /slash commands
  | 'file'                            // Files + directories
  | 'shell'                           // Bash completions
  | 'slack'                           // Slack #channels
  | 'history'                         // /resume sessions
  | 'none'                            // No suggestions

Debouncing Strategy

Uses useDebounceCallback from usehooks-ts with 250ms debounce for suggestion generation. Each keystroke cancels the previous pending suggestion computation via AbortController on shell completions.

// Shell completion has its own AbortController to prevent race conditions
let currentShellCompletionAbortController: AbortController | null = null
async function generateBashSuggestions(input, cursorOffset) {
  if (currentShellCompletionAbortController) {
    currentShellCompletionAbortController.abort()
  }
  currentShellCompletionAbortController = new AbortController()
  const suggestions = await getShellCompletions(
    input, cursorOffset,
    currentShellCompletionAbortController.signal
  )
  return suggestions
}

Selection Preservation Algorithm

When suggestions are regenerated (e.g., user types), the hook preserves the previously selected suggestion by matching IDs:

function getPreservedSelection(
  prevSuggestions: SuggestionItem[],
  prevSelection: number,
  newSuggestions: SuggestionItem[]
): number {
  if (newSuggestions.length === 0) return -1
  if (prevSelection < 0) return 0

  const prevSelectedItem = prevSuggestions[prevSelection]
  if (!prevSelectedItem) return 0

  const newIndex = newSuggestions.findIndex(
    item => item.id === prevSelectedItem.id
  )
  return newIndex >= 0 ? newIndex : 0
}

Token Extraction (Complex Quoted Path Handling)

export function extractCompletionToken(
  text: string,
  cursorPos: number,
  includeAtSymbol = false
): {
  token: string
  startPos: number
  isQuoted?: boolean
} | null {
  // Handles: @"path with spaces", @path/to/file, ~/path, etc.
  // Fast path: lastIndexOf to avoid expensive $ regex on long inputs
  // Quoted path: scans after cursor to include closing quote
}

Suggestion Application Functions

// File @ mention: @displayText (adds trailing space)
export function formatReplacementValue(options: {
  displayText: string
  mode: string                 // 'bash' or 'prompt'
  hasAtPrefix: boolean
  needsQuotes: boolean
  isQuoted?: boolean
  isComplete: boolean
}): string {
  const space = isComplete ? ' ' : ''
  if (isQuoted || needsQuotes) {
    return mode === 'bash' ? `"${displayText}"${space}` : `@"${displayText}"${space}`
  } else if (hasAtPrefix) {
    return mode === 'bash' ? `${displayText}${space}` : `@${displayText}${space}`
  }
  return displayText
}

// Directory suggestion: @path/to/dir/ (adds trailing /)
export function applyDirectorySuggestion(
  input: string,
  suggestionId: string,
  tokenStartPos: number,
  tokenLength: number,
  isDirectory: boolean
): { newInput: string; cursorPos: number } {
  const suffix = isDirectory ? '/' : ' '
  const before = input.slice(0, tokenStartPos)
  const after = input.slice(tokenStartPos + tokenLength)
  const replacement = '@' + suggestionId + suffix
  const newInput = before + replacement + after
  return { newInput, cursorPos: before.length + replacement.length }
}

// Shell completion: replaces word after last space
export function applyShellSuggestion(
  suggestion: SuggestionItem,
  input: string,
  cursorOffset: number,
  onInputChange: (value: string) => void,
  setCursorOffset: (offset: number) => void,
  completionType: ShellCompletionType | undefined
): void {
  const beforeCursor = input.slice(0, cursorOffset)
  const lastSpaceIndex = beforeCursor.lastIndexOf(' ')
  const wordStart = lastSpaceIndex + 1

  let replacementText: string
  if (completionType === 'variable') {
    replacementText = '$' + suggestion.displayText + ' '
  } else if (completionType === 'command') {
    replacementText = suggestion.displayText + ' '
  } else {
    replacementText = suggestion.displayText
  }

  const newInput = input.slice(0, wordStart) + replacementText + input.slice(cursorOffset)
  onInputChange(newInput)
  setCursorOffset(wordStart + replacementText.length)
}

Keyboard Navigation

Up/Down: Cycle through suggestions, wrapping at edges
Tab: Accept currently selected suggestion
Escape: Dismiss suggestions
Enter: Conditionally submits based on suggestion type (command auto-submits, files require Tab first)

File Suggestion System

File: `fileSuggestions.ts` (811 lines)

Bridges Anthropic's native Rust FileIndex with git tracking, ignore patterns, and background refresh logic.

Singleton Pattern

let fileIndex: FileIndex | null = null

function getFileIndex(): FileIndex {
  if (!fileIndex) {
    fileIndex = new FileIndex()
  }
  return fileIndex
}

export function clearFileSuggestionCaches(): void {
  fileIndex = null
  fileListRefreshPromise = null
  cacheGeneration++
  untrackedFetchPromise = null
  cachedTrackedFiles = []
  cachedConfigFiles = []
  cachedTrackedDirs = []
  indexBuildComplete.clear()
  ignorePatternsCache = null
  ignorePatternsCacheKey = null
  lastRefreshMs = 0
  lastGitIndexMtime = null
  loadedTrackedSignature = null
  loadedMergedSignature = null
}

Native Rust Integration

// From native-ts/file-index/index.js
import {
  CHUNK_MS,                 // Milliseconds between event loop yields
  FileIndex,
  yieldToEventLoop,
} from '../native-ts/file-index/index.js'

// FileIndex API
fileIndex.loadFromFileListAsync(paths).done  // Returns Promise<void>
fileIndex.fuzzyMatch(query, limit)           // Rust fuzleo matching
fileIndex.restart()                          // Reset state (call after loadFromFileListAsync)

Refresh Throttling Strategy

Two triggers control index rebuilds:

Git Index Mtime (Immediate): When .git/index changes (tracked files modified)
Time Floor (5s): Periodic refresh for untracked files

let lastRefreshMs = 0
let lastGitIndexMtime: number | null = null

function getGitIndexMtime(): number | null {
  const repoRoot = findGitRoot(getCwd())
  if (!repoRoot) return null
  try {
    return statSync(path.join(repoRoot, '.git', 'index')).mtimeMs
  } catch {
    return null  // worktrees, fresh repos, non-git
  }
}

// In startBackgroundCacheRefresh():
const now = Date.now()
const gitMtime = getGitIndexMtime()
const timeSinceLastRefresh = now - lastRefreshMs

// Rebuild if git changed OR 5s elapsed
if ((gitMtime !== null && gitMtime !== lastGitIndexMtime) || timeSinceLastRefresh >= 5000) {
  // ... rebuild index
}

Path Signature for Change Detection

Hashes a path list using a rolling window to detect git operations without spawning:

export function pathListSignature(paths: string[]): string {
  const n = paths.length
  const stride = Math.max(1, Math.floor(n / 500))  // Sample every Nth path
  let h = 0x811c9dc5 | 0  // FNV-1a hash init

  for (let i = 0; i < n; i += stride) {
    const p = paths[i]!
    for (let j = 0; j < p.length; j++) {
      h = ((h ^ p.charCodeAt(j)) * 0x01000193) | 0
    }
    h = (h * 0x01000193) | 0
  }

  // Always hash last path (catches single-file add/rm at tail)
  if (n > 0) {
    const last = paths[n - 1]!
    for (let j = 0; j < last.length; j++) {
      h = ((h ^ last.charCodeAt(j)) * 0x01000193) | 0
    }
  }

  return `${n}:${(h >>> 0).toString(16)}`
}

On a 346k-path repo, this hashes ~700 paths instead of 14MB, completing in <1ms.

Git Path Normalization

function normalizeGitPaths(
  files: string[],
  repoRoot: string,
  originalCwd: string,
): string[] {
  if (originalCwd === repoRoot) return files
  return files.map(f => {
    const absolutePath = path.join(repoRoot, f)
    return path.relative(originalCwd, absolutePath)
  })
}

Ignore Pattern Caching

Ripgrep-specific patterns (.ignore, .rgignore) cached by repoRoot:cwd key:

let ignorePatternsCache: ReturnType<typeof ignore> | null = null
let ignorePatternsCacheKey: string | null = null

function loadIgnorePatterns(): ReturnType<typeof ignore> | null {
  const repoRoot = findGitRoot(getCwd())
  const cwd = getCwd()
  const key = `${repoRoot}:${cwd}`

  if (ignorePatternsCacheKey === key && ignorePatternsCache) {
    return ignorePatternsCache
  }

  // Load .ignore/.rgignore and cache
  ignorePatternsCacheKey = key
  // ... populate ignorePatternsCache
  return ignorePatternsCache
}

Untracked File Background Fetch

Spawns git ls-files --others in background and merges results asynchronously:

let untrackedFetchPromise: Promise<void> | null = null

async function fetchUntrackedFilesInBackground(): Promise<void> {
  if (untrackedFetchPromise) {
    return untrackedFetchPromise  // Deduplicate in-flight requests
  }

  untrackedFetchPromise = (async () => {
    try {
      const files = await execFileNoThrowWithCwd('git', ['ls-files', '--others', '--exclude-standard'])
      const repoRoot = findGitRoot(getCwd())
      if (!repoRoot) return

      const normalized = normalizeGitPaths(files, repoRoot, getCwd())
      await mergeUntrackedIntoNormalizedCache(normalized)
    } finally {
      untrackedFetchPromise = null
    }
  })()

  return untrackedFetchPromise
}

Two-Signature System for Preventing Index Ping-Pong

// Tracks what's loaded in Rust to avoid duplicate restarts
let loadedTrackedSignature: string | null = null      // From git ls-files
let loadedMergedSignature: string | null = null       // After untracked merge

// On tracked-only update
await fileIndex.loadFromFileListAsync(trackedFiles).done
loadedTrackedSignature = sig
// Don't update loadedMergedSignature — untracked merge will do it

// On tracked + untracked merge
const allPaths = [
  ...cachedTrackedFiles,
  ...cachedConfigFiles,
  ...cachedTrackedDirs,
  ...normalizedUntracked,
  ...untrackedDirs,
]
const sig = pathListSignature(allPaths)
if (sig === loadedMergedSignature) {
  // Skip rebuild — already loaded this exact set
  return
}
await fileIndex.loadFromFileListAsync(allPaths).done
loadedMergedSignature = sig

Suggestion Generation Pipeline

export async function generateFileSuggestions(
  query: string,
  showOnEmpty: boolean = false,
): Promise<SuggestionItem[]> {
  if (!query && !showOnEmpty) return []

  // Cold-start: ensure index is populated
  await ensureIndexRefreshPromise()

  // Trigger background untracked fetch (async, no await)
  startBackgroundCacheRefresh()

  // Rust fuzzy match on loaded file list
  const results = fileIndex.fuzzyMatch(query, 50)

  return results.map(path => ({
    id: `file-${path}`,
    displayText: path,
    description: path,
    metadata: { score: /* rust score */ },
  }))
}

Voice Pipeline Architecture

Files: `useVoice.ts` (1,144 lines) + `useVoiceIntegration.tsx` (676 lines)

Hold-to-talk STT pipeline using Anthropic's voice_stream endpoint (Deepgram backend).

Architecture Diagram

useVoiceIntegration.tsx (UI dispatcher, 676 lines)
│
├─ useVoice.ts (Core STT logic, 1,144 lines)
│  ├─ Native Audio Capture
│  │  └─ voice.ts (lazy-loaded, NAPI)
│  │     ├─ macOS: native audio module
│  │     └─ Linux: SoX executable
│  ├─ Voice Stream Connection
│  │  └─ voiceStreamSTT.ts
│  │     ├─ connectVoiceStream() - WebSocket init
│  │     ├─ VoiceStreamConnection type
│  │     └─ isVoiceStreamAvailable() - capability check
│  ├─ STT Language Detection
│  │  ├─ getSystemLocaleLanguage() - OS locale
│  │  ├─ normalizeLanguageForSTT() - BCP-47 mapping
│  │  └─ LANGUAGE_NAME_TO_CODE map (19 languages)
│  ├─ Recording State Machine
│  │  ├─ state: 'idle' | 'recording' | 'processing'
│  │  ├─ Release timer (RELEASE_TIMEOUT_MS = 200ms)
│  │  └─ Focus mode timeout (FOCUS_SILENCE_TIMEOUT_MS = 5000ms)
│  └─ Audio Visualization
│     ├─ computeLevel() - RMS amplitude → normalized 0-1
│     └─ AUDIO_LEVEL_BARS = 16 (waveform bars)
│
└─ Keybinding Integration
   └─ useCommandKeybindings.tsx
      └─ Hold-to-talk trigger (configurable key)

Language Support

27 language codes + name→code mappings stored in client-side allowlist. Server-side GrowthBook gate controls accepted languages; unsupported codes trigger WebSocket 1008 "Unsupported language" close.

const LANGUAGE_NAME_TO_CODE: Record<string, string> = {
  english: 'en', spanish: 'es', french: 'fr', japanese: 'ja',
  german: 'de', portuguese: 'pt', italian: 'it', korean: 'ko',
  hindi: 'hi', indonesian: 'id', russian: 'ru', polish: 'pl',
  turkish: 'tr', dutch: 'nl', ukrainian: 'uk', greek: 'el',
  czech: 'cs', danish: 'da', swedish: 'sv', norwegian: 'no',
  // Native names also supported:
  日本語: 'ja', 한국어: 'ko', हिन्दी: 'hi', ελληνικά: 'el', ...
}

const SUPPORTED_LANGUAGE_CODES = new Set([
  'en', 'es', 'fr', 'ja', 'de', 'pt', 'it', 'ko', 'hi', 'id',
  'ru', 'pl', 'tr', 'nl', 'uk', 'el', 'cs', 'da', 'sv', 'no'
])

export function normalizeLanguageForSTT(language: string | undefined): {
  code: string
  fellBackFrom?: string
} {
  if (!language) return { code: 'en' }
  const lower = language.toLowerCase().trim()
  if (!lower) return { code: 'en' }
  if (SUPPORTED_LANGUAGE_CODES.has(lower)) return { code: lower }
  const fromName = LANGUAGE_NAME_TO_CODE[lower]
  if (fromName) return { code: fromName }
  const base = lower.split('-')[0]  // e.g., 'zh-Hans' → 'zh'
  if (base && SUPPORTED_LANGUAGE_CODES.has(base)) return { code: base }
  return { code: 'en', fellBackFrom: language }  // Default + warning
}

Key Release Detection via Auto-Repeat Timer

macOS/Linux keyboard auto-repeat fires ~every 30-80ms. The hook detects release by waiting 200ms without a new key event:

const RELEASE_TIMEOUT_MS = 200     // Gap signals key release
const REPEAT_FALLBACK_MS = 600     // Headroom for auto-repeat jitter
const FIRST_PRESS_FALLBACK_MS = 2000  // OS initial repeat delay

export function useVoice({
  onTranscript,
  onError,
  enabled,
  focusMode,
}: UseVoiceOptions): UseVoiceReturn {
  const [state, setState] = useState<VoiceState>('idle')
  const releaseTimerRef = useRef<NodeJS.Timeout | null>(null)
  const connectionRef = useRef<VoiceStreamConnection | null>(null)

  const handleKeyEvent = useCallback((fallbackMs?: number) => {
    // Clear existing timer (auto-repeat pushed key release further out)
    if (releaseTimerRef.current) {
      clearTimeout(releaseTimerRef.current)
    }

    // Start recording if idle
    if (state === 'idle') {
      setState('recording')
      // ... initialize audio capture
    }

    // Arm new release timer
    releaseTimerRef.current = setTimeout(() => {
      if (state === 'recording') {
        setState('processing')
        // ... finalize audio, send to voice_stream
      }
    }, fallbackMs ?? RELEASE_TIMEOUT_MS)
  }, [state])

  return { state, handleKeyEvent }
}

Audio Level Computation (RMS + Sqrt Curve)

export function computeLevel(chunk: Buffer): number {
  const samples = chunk.length >> 1  // 16-bit = 2 bytes/sample
  if (samples === 0) return 0

  let sumSq = 0
  for (let i = 0; i < chunk.length - 1; i += 2) {
    const sample = ((chunk[i]! | (chunk[i + 1]! << 8)) << 16) >> 16  // 16-bit signed LE
    sumSq += sample * sample
  }

  const rms = Math.sqrt(sumSq / samples)
  const normalized = Math.min(rms / 2000, 1)  // Scale to 0-1
  return Math.sqrt(normalized)  // Sqrt curve spreads quiet levels
}

The sqrt curve ensures the waveform visualizer uses the full height range even for quiet speech.

Lazy Voice Module Loading

Defers importing native audio module until user activates voice to avoid TCC permission prompts on macOS:

type VoiceModule = typeof import('../services/voice.js')
let voiceModule: VoiceModule | null = null

const { recordAudio } = await (async () => {
  if (!voiceModule) {
    voiceModule = await import('../services/voice.js')
  }
  return voiceModule
})()

const audioBuffer = await recordAudio(duration)

Focus Mode Lifecycle

When focused, maintains a WebSocket connection and auto-terminates after 5s of silence:

const FOCUS_SILENCE_TIMEOUT_MS = 5_000

// On focus → restart timer
useEffect(() => {
  if (!focusMode) return

  const silenceTimer = setTimeout(() => {
    // Tear down connection after 5s silence
    connectionRef.current?.close()
    connectionRef.current = null
  }, FOCUS_SILENCE_TIMEOUT_MS)

  return () => clearTimeout(silenceTimer)
}, [focusMode])

Voice Stream Connection Lifecycle

async function connectToVoiceStream(
  language: string,
  onChunk: (text: string, isFinal: boolean) => void,
): Promise<VoiceStreamConnection> {
  const connection = await connectVoiceStream({
    language,  // BCP-47 code
    keyTerms: getVoiceKeyterms(),  // Domain-specific words (commands, file names)
    onMessage: (msg) => {
      if (msg.type === 'transcript') {
        onChunk(msg.transcript, msg.isFinal)
      }
    },
  })

  return connection
}

// Send audio chunks as recording streams in
connection.send(audioChunk)

// When done:
const finalTranscript = await connection.finalize('user')  // FinalizeSource

Team/Swarm Hooks

File: `useInboxPoller.ts` (969 lines)

Core hook for distributed team coordination. Polls mailbox files for inter-agent messages and delivers them as turns.

Mailbox Protocol

// Mailbox structure in .claude-code-team/
{
  agent_name}/inbox/       // Per-agent mailbox
├─ unread/                // Unread messages (atomic move)
│  └─ {uuid}.json
└─ archive/               // Read messages (tombstone)
   └─ {uuid}.json

Messages are file-based, not HTTP:

interface TeammateMessage {
  id: string               // UUID
  from: string             // Agent name
  type: 'text' | 'xml' | 'tool_use_confirm' | ...
  text: string             // Content
  timestamp: number        // Unix ms
}

// Read unread messages by agent
const unread = await readUnreadMessages(
  agentName,               // Polling agent
  teamContext?.teamName    // Team file location
)

Poll Interval & Frequency

const INBOX_POLL_INTERVAL_MS = 1000  // 1 second

Polls every second, but skips if:

Hook disabled (supervisor not running)
Already loading (previous turn still executing)
Modal dialog focused (not appropriate for interruption)

const poll = useCallback(async () => {
  if (!enabled) return                        // Hook disabled
  const currentAppState = store.getState()
  const agentName = getAgentNameToPoll(currentAppState)
  if (!agentName) return                      // Not in swarm

  const unread = await readUnreadMessages(agentName, teamContext?.teamName)
  if (unread.length === 0) return            // No new messages

  // ... process and deliver
}, [enabled, store, teamContext])

useInterval(poll, INBOX_POLL_INTERVAL_MS)

Agent Name Resolution

Determines which mailbox to poll based on context:

function getAgentNameToPoll(appState: AppState): string | undefined {
  if (isInProcessTeammate()) {
    return undefined  // Use waitForNextPromptOrShutdown() instead
  }
  if (isTeammate()) {
    return getAgentName()  // Process-based teammate
  }
  if (isTeamLead(appState.teamContext)) {
    const leadAgentId = appState.teamContext!.leadAgentId
    return appState.teamContext!.teammates[leadAgentId]?.name || 'team-lead'
  }
  return undefined
}

Message Processing Pipeline

Plan Approval Responses: Check if teammate is in plan mode awaiting leader approval
Permission Responses: Unblock waiting tool use via swarm permission bridge
Sandbox Responses: Unblock waiting sandbox operations
Tool Use Confirmations: Queue for user interaction or auto-approve
Regular Messages: Queue in AppState.inbox or submit immediately if idle

// Check for plan approval from team lead (security: verify sender)
if (isTeammate() && isPlanModeRequired()) {
  for (const msg of unread) {
    const approvalResponse = isPlanApprovalResponse(msg.text)
    if (approvalResponse && msg.from === 'team-lead') {  // ← Security check
      setAppState(prev => ({
        ...prev,
        toolPermissionContext: applyPermissionUpdate(
          prev.toolPermissionContext,
          {
            type: 'setMode',
            mode: toExternalPermissionMode(approvalResponse.permissionMode ?? 'default'),
            destination: 'session',
          },
        ),
      }))
    }
  }
}

// Handle permission responses (workers wait for these)
if (hasPermissionCallback(msg.text)) {
  const callback = getPermissionCallback(msg.text)
  if (callback) {
    callback(processMailboxPermissionResponse(msg.text))
  }
}

// Submit as turn if idle, queue if busy
if (isLoading) {
  setAppState(prev => ({
    ...prev,
    inbox: {
      messages: [...prev.inbox.messages, msg],
    },
  }))
} else {
  const submitted = onSubmitMessage(formatted)
  if (submitted) {
    markRead()
  }
}

Message Formatting & Delivery

const formatted = createAssistantMessage({
  text: msg.text,
  // Tool use confirmations get special formatting
  toolUseConfirms: msg.toolUseConfirms,
})

// Try to submit; on rejection (query running), leave unread
const success = onSubmitMessage(formatted)
if (success) {
  await markMessagesAsRead([msg.id], agentName)
}

File: `useSwarmPermissionPoller.ts` (330 lines)

Worker-side hook that polls for permission responses from the team leader. Paired with useInboxPoller on the leader side.

Permission Request/Response Flow

Worker Agent                          Leader Agent
┌──────────────┐                     ┌──────────────┐
│              │                     │              │
│ useCanUseTool│                     │ useInboxPoller
│ (worker)     │                     │ (leader)     │
│              │                     │              │
│ 1. Create    │  2. Write to       │ 3. Poll      │
│    pending   │     mailbox        │    mailbox   │
│    request   │ ─────────────────→ │ 4. Show      │
│              │                     │    prompt    │
│ 5. Poll      │  6. Write          │ 7. Get user  │
│    for       │     response       │    response  │
│    response  │ ←─────────────────  │              │
│              │                     │              │
│ 8. Call      │                     │              │
│    callback  │                     │              │
│              │                     │              │
└──────────────┘                     └──────────────┘

Poll Strategy & Interval

const POLL_INTERVAL_MS = 500  // 500ms (faster than inbox, since response awaited)

export function useSwarmPermissionPoller({
  enabled,
  onResponse,
}: Props): void {
  const poll = useCallback(async () => {
    if (!enabled) return
    if (!isSwarmWorker()) return

    const agentName = getAgentName()
    const teamName = getTeamName()

    const response = await pollForResponse(agentName, teamName)
    if (!response) return

    // Parse and validate permissionUpdates from response
    const updates = parsePermissionUpdates(response.permissionUpdates)

    // Call the registered callback
    onResponse({
      toolUseID: response.toolUseID,
      decision: response.decision,
      permissionUpdates: updates,
    })

    // Clean up response file to prevent re-reading
    await removeWorkerResponse(agentName, response.responseId)
  }, [enabled, onResponse])

  useInterval(poll, POLL_INTERVAL_MS)
}

Permission Update Validation

Malformed responses from buggy teammate processes are filtered:

function parsePermissionUpdates(raw: unknown): PermissionUpdate[] {
  if (!Array.isArray(raw)) return []

  const schema = permissionUpdateSchema()  // Zod schema
  const valid: PermissionUpdate[] = []

  for (const entry of raw) {
    const result = schema.safeParse(entry)
    if (result.success) {
      valid.push(result.data)
    } else {
      logForDebugging(
        `[SwarmPermissionPoller] Dropping malformed permissionUpdate: ${result.error.message}`,
        { level: 'warn' }
      )
    }
  }
  return valid
}

Remote Session Management

File: `useReplBridge.tsx` (722 lines)

Always-on WebSocket bridge to claude.ai. Maintains persistent session on remote, syncs messages bidirectionally.

Bridge Lifecycle

┌─ replBridgeEnabled toggles
│
├─ enabled=true
│  ├─ Wait for previous teardown
│  ├─ Call initReplBridge() → new Environment on remote
│  ├─ Connect WebSocket to /subscribe
│  ├─ Flush initial messages (avoid duplication)
│  ├─ Listen for remote messages → queuedCommands
│  └─ Watch messages, write new ones to bridge
│
├─ enabled=false
│  ├─ Call deregisterEnvironment() → cleanup remote
│  └─ Close WebSocket
│
└─ Failure fuse: after 3 consecutive init failures → auto-disable

Bridge State Machine

export enum BridgeState {
  Idle = 'idle',
  Connecting = 'connecting',
  Connected = 'connected',
  Disconnected = 'disconnected',
  Failed = 'failed',
}

interface ReplBridgeHandle {
  writeMessages(messages: Message[]): Promise<void>
  cancelRequest(): Promise<void>
  getState(): BridgeState
}

Message Flushing (Deduplication)

To avoid duplicate messages when bridge reconnects, tracks UUIDs of flushed messages:

const flushedUUIDsRef = useRef(new Set<string>())

// On init, flush all messages from history
const initialMessages = messages.slice(0, initialMessageCount)
for (const msg of initialMessages) {
  if (msg.message?.id) {
    flushedUUIDsRef.current.add(msg.message.id)
  }
}

// After reconnect, only write NEW messages (not in flushedUUIDs)
const newMessages = messages.slice(lastWrittenIndexRef.current)
for (const msg of newMessages) {
  if (msg.message?.id && !flushedUUIDsRef.current.has(msg.message.id)) {
    await writeMessages([msg])
    flushedUUIDsRef.current.add(msg.message.id)
  }
}

Failure Handling & Fuse Logic

const consecutiveFailuresRef = useRef(0)
const MAX_CONSECUTIVE_INIT_FAILURES = 3

// On successful init
consecutiveFailuresRef.current = 0
logForDebugging('[bridge:repl] Init succeeded, failures reset to 0')

// On init failure
consecutiveFailuresRef.current++
if (consecutiveFailuresRef.current >= MAX_CONSECUTIVE_INIT_FAILURES) {
  const fuseHint = 'disabled after repeated failures · restart to retry'
  logForDebugging(`[bridge:repl] ${consecutiveFailuresRef.current} failures, fuse blown`)

  setAppState(prev => ({
    ...prev,
    replBridgeError: fuseHint,
    replBridgeEnabled: false,  // ← Prevent infinite retry loop
  }))

  addNotification({
    key: 'bridge-failed',
    jsx: <>
      <Text color="error">Remote Control failed</Text>
      <Text dimColor> · {fuseHint}</Text>
    </>,
    priority: 'immediate',
  })
  return
}

// Schedule auto-clear of replBridgeEnabled after 10s
const failureTimeoutRef = useRef<ReturnType<typeof setTimeout> | undefined>()
failureTimeoutRef.current = setTimeout(() => {
  setAppState(prev => ({
    ...prev,
    replBridgeEnabled: false,
  }))
}, BRIDGE_FAILURE_DISMISS_MS)

Inbound Message Processing

Remote messages are converted to queuedCommands:

async function onBridgeMessage(msg: SDKMessage) {
  // Filter echoed user messages (avoid duplicates)
  if (convertUserTextMessages && sentUUIDsRef.current.has(msg.uuid)) {
    sentUUIDsRef.current.delete(msg.uuid)  // ← Consume from ring
    return
  }

  // Convert SDK message to REPL message
  const replMessages = convertSDKMessage(msg)

  // Queue for injection into message stream
  enqueue(replMessages)
}

Failure Dismiss Timeout

export const BRIDGE_FAILURE_DISMISS_MS = 10_000  // 10 seconds

After a failure, the hook auto-clears replBridgeEnabled after 10s to stop retry attempts.

File: `useRemoteSession.ts` (605 lines)

Manages CCR (Cloud Code Runner) session via WebSocket. Adapter between SDK messages and REPL message format.

Remote Session Manager

const config: RemoteSessionConfig = {
  sessionId: string
  WebSocketURL: string
  apiEndpoint: string
  token: string
}

const manager = new RemoteSessionManager(config)

// Lifecycle
await manager.connect()     // WebSocket to /subscribe
await manager.sendMessage(content)  // HTTP POST /input
await manager.disconnect()  // Close WebSocket

Response Timeout Handling

const RESPONSE_TIMEOUT_MS = 60000      // 60 seconds (normal)
const COMPACTION_TIMEOUT_MS = 180000   // 3 minutes (during index rebuild)

const isCompactingRef = useRef(false)

useEffect(() => {
  if (isCompactingRef.current) {
    // During compaction, suppress timeout warnings
    clearTimeout(responseTimeoutRef.current)
    responseTimeoutRef.current = null
    logForDebugging('[remote] Suppressing timeout during compaction')
  } else if (responseTimeoutRef.current) {
    // Re-arm normal timeout after compaction
    logForDebugging('[remote] Compaction complete, re-arming timeout')
    responseTimeoutRef.current = setTimeout(() => {
      setConnStatus('unresponsive')
    }, RESPONSE_TIMEOUT_MS)
  }
}, [isCompactingRef.current])

Running Task Tracking (Event-Sourced)

Remote process tasks live in a separate process. Track them via task_started/task_ended messages:

const runningTaskIdsRef = useRef(new Set<string>())

function onTaskStarted(taskId: string) {
  runningTaskIdsRef.current.add(taskId)
  writeTaskCount()
}

function onTaskEnded(taskId: string) {
  runningTaskIdsRef.current.delete(taskId)
  writeTaskCount()
}

function writeTaskCount() {
  const n = runningTaskIdsRef.current.size
  setAppState(prev =>
    prev.remoteBackgroundTaskCount === n ? prev : {
      ...prev,
      remoteBackgroundTaskCount: n,
    }
  )
}

Permission State Machine

Files: `toolPermission/PermissionContext.ts` (388 lines) + handlers (3 files, 760 LOC)

Hierarchical permission system with multiple decision sources: user interactive prompts, classifier auto-approval, hooks, swarm workers, team leads.

Permission Decision Flow Diagram

Tool Use Requested
│
├─ [1] Check hook allowlist
│  ├─ Allowed? → executePermissionRequestHooks()
│  └─ Rejected? → Abort with hook feedback
│
├─ [2] Check classifier (BASH_CLASSIFIER feature)
│  ├─ Bash tool? → awaitClassifierAutoApproval()
│  ├─ Auto-allowed? → Decision(behavior: 'allow')
│  ├─ Unsafe? → Decision(behavior: 'ask')
│  └─ Uncertain? → Fall through to user
│
├─ [3] User interactive prompt (if not auto-approved)
│  ├─ Standalone session? → Show prompt in REPL
│  ├─ Swarm worker? → Send permission request to leader via mailbox
│  ├─ Swarm leader? → Show prompt + collect subfeedback from teammates
│  └─ In-process teammate? → Wait for parent context decision
│
├─ [4] Timeout or abort?
│  └─ User disconnects/Ctrl+C → Reject + log cancellation
│
└─ Decision → Log + Persist + Execute or Reject

PermissionContext Creation

function createPermissionContext(
  tool: ToolType,
  input: Record<string, unknown>,
  toolUseContext: ToolUseContext,
  assistantMessage: AssistantMessage,
  toolUseID: string,
  setToolPermissionContext: (context: ToolPermissionContext) => void,
  queueOps?: PermissionQueueOps,
) {
  const messageId = assistantMessage.message.id

  const ctx = {
    tool,
    input,
    toolUseContext,
    assistantMessage,
    messageId,
    toolUseID,

    // Method: Log permission decision with full context
    logDecision(
      args: PermissionDecisionArgs,
      opts?: {
        input?: Record<string, unknown>
        permissionPromptStartTimeMs?: number
      },
    ) {
      logPermissionDecision({
        tool,
        input: opts?.input ?? input,
        toolUseContext,
        messageId,
        toolUseID,
      }, args, opts?.permissionPromptStartTimeMs)
    },

    // Method: Log cancellation due to user abort (Ctrl+C)
    logCancelled() {
      logEvent('tengu_tool_use_cancelled', {
        messageID: messageId as AnalyticsMetadata_I_VERIFIED_THIS_IS_NOT_CODE_OR_FILEPATHS,
        toolName: sanitizeToolNameForAnalytics(tool.name),
      })
    },

    // Method: Persist permission updates to disk
    async persistPermissions(updates: PermissionUpdate[]) {
      if (updates.length === 0) return false
      persistPermissionUpdates(updates)
      const appState = toolUseContext.getAppState()
      setToolPermissionContext(
        applyPermissionUpdates(appState.toolPermissionContext, updates),
      )
      return updates.some(update => supportsPersistence(update.destination))
    },

    // Method: Check if request was aborted (Ctrl+C)
    resolveIfAborted(resolve: (decision: PermissionDecision) => void): boolean {
      if (!toolUseContext.abortController.signal.aborted) return false
      this.logCancelled()
      resolve(this.cancelAndAbort(undefined, true))
      return true
    },

    // Method: Reject with optional feedback + memory correction hint
    cancelAndAbort(
      feedback?: string,
      isAbort?: boolean,
      contentBlocks?: ContentBlockParam[],
    ): PermissionDecision {
      const sub = !!toolUseContext.agentId
      const baseMessage = feedback
        ? `${sub ? SUBAGENT_REJECT_MESSAGE_WITH_REASON_PREFIX : REJECT_MESSAGE_WITH_REASON_PREFIX}${feedback}`
        : sub
          ? SUBAGENT_REJECT_MESSAGE
          : REJECT_MESSAGE
      const message = sub ? baseMessage : withMemoryCorrectionHint(baseMessage)

      if (isAbort || (!feedback && !contentBlocks?.length && !sub)) {
        logForDebugging(
          `Aborting: tool=${tool.name} isAbort=${isAbort} hasFeedback=${!!feedback} isSubagent=${sub}`,
        )
        toolUseContext.abortController.abort()
      }
      return { behavior: 'ask', message, contentBlocks }
    },

    // Method: Try classifier auto-approval (BASH_CLASSIFIER feature)
    async tryClassifier(
      pendingClassifierCheck: PendingClassifierCheck | undefined,
      updatedInput: Record<string, unknown> | undefined,
    ): Promise<PermissionDecision | null> {
      if (tool.name !== BASH_TOOL_NAME || !pendingClassifierCheck) {
        return null
      }
      const classifierDecision = await awaitClassifierAutoApproval(
        pendingClassifierCheck,
        toolUseContext.abortController.signal,
        toolUseContext.options.isNonInteractiveSession,
      )
      if (!classifierDecision) return null

      // Log classifier approval for transcript analysis
      if (feature('TRANSCRIPT_CLASSIFIER') && classifierDecision.type === 'classifier') {
        const matchedRule = classifierDecision.reason.match(/^Allowed by prompt rule: "(.+)"$/)?.[1]
        if (matchedRule) {
          setClassifierApproval(toolUseID, matchedRule)
        }
      }
      return classifierDecision
    },
  }

  return ctx
}

Permission Decision Types

type PermissionApprovalSource =
  | { type: 'hook'; permanent?: boolean }
  | { type: 'user'; permanent: boolean }
  | { type: 'classifier' }

type PermissionRejectionSource =
  | { type: 'hook' }
  | { type: 'user_abort' }
  | { type: 'user_reject'; hasFeedback: boolean }

type PermissionDecision =
  | { behavior: 'allow'; approvalSource: PermissionApprovalSource }
  | { behavior: 'reject'; rejectSource: PermissionRejectionSource }
  | { behavior: 'ask'; message: string; contentBlocks?: ContentBlockParam[] }

Interactive Handler (536 lines)

Manages user prompts for tool confirmation:

// Shows <ToolUseConfirm> component in footer
// Waits for user decision (allow, reject with feedback, abort)
// On feedback: logs decision + renders updated message with feedback metadata

Swarm Worker Handler (159 lines)

When worker requests permission:

// 1. Create pending request with UUID
// 2. Write to leader mailbox (file-based)
// 3. Poll for response (via useSwarmPermissionPoller)
// 4. Apply response (permission updates + decision)
// 5. Call callback (onAllow/onReject)

Permission Logging (238 lines)

Event-sourced decision logging:

export function logPermissionDecision(
  context: PermissionDecisionArgs,
  decision: PermissionDecision,
  promptStartTimeMs?: number,
) {
  const eventName = `tengu_permission_${decision.type}`  // 'tengu_permission_allow', etc.

  logEvent(eventName, {
    toolName: sanitizeToolNameForAnalytics(context.tool.name),
    messageID: context.messageId,
    toolUseID: context.toolUseID,
    source: decision.approvalSource?.type ?? decision.rejectSource?.type,
    durationMs: promptStartTimeMs ? Date.now() - promptStartTimeMs : undefined,
    agentId: context.toolUseContext.agentId,
    isPermanent: (decision as any)?.permanent ?? false,
  })
}

Notification System

Directory: `notifs/` (16 hooks, 1,342 LOC)

Context-aware lifecycle notifications for IDE status, MCP connectivity, rate limits, model migrations, etc.

Hook Catalog

Hook	LOC	Purpose
`useFastModeNotification.tsx`	161	Fast mode toggle + availability
`useIDEStatusIndicator.tsx`	185	IDE connection status → footer indicator
`useLspInitializationNotification.tsx`	142	LSP server init progress
`useMcpConnectivityStatus.tsx`	87	MCP server health monitoring
`useRateLimitWarningNotification.tsx`	113	API rate limit warnings
`usePluginInstallationStatus.tsx`	127	Plugin install/update progress
`useDeprecationWarningNotification.tsx`	43	Feature deprecation notices
`useCanSwitchToExistingSubscription.tsx`	59	Subscription migration prompts
`usePluginAutoupdateNotification.tsx`	82	Plugin auto-update availability
`useModelMigrationNotifications.tsx`	51	Model deprecation/migration
`useTeammateShutdownNotification.ts`	78	Teammate session shutdown
`useAutoModeUnavailableNotification.ts`	56	Auto mode gating
`useSettingsErrors.tsx`	68	Settings parse/validation errors
`useOfficialMarketplaceNotification.tsx`	47	Plugin marketplace announcements
`useInstallMessages.tsx`	25	Package install messages
`useStartupNotification.ts`	41	Startup info messages
`useNpmDeprecationNotification.ts`	24	npm deprecation warnings

Lifecycle Pattern

Most notifications follow this pattern:

export function useExampleNotification(): void {
  const { addNotification, removeNotification } = useNotifications()
  const [seen, setSeen] = useState(false)

  useEffect(() => {
    if (seen || !shouldShow()) return

    // Show notification
    const key = 'unique-key-for-notification'
    addNotification({
      key,
      jsx: <NotificationContent />,
      priority: 'normal',  // or 'immediate'
      dismissable: true,
      onDismiss: () => {
        setSeen(true)
        // Optional: persist that user dismissed
      },
    })
  }, [seen, ...dependencies])
}

IDE Status Indicator Example

// useIDEStatusIndicator.tsx (185 lines)
export function useIDEStatusIndicator(): void {
  const ideConnectionStatus = useAppState(s => s.ideConnectionStatus)
  const ideSelection = useAppState(s => s.ideSelection)
  const { addNotification, removeNotification } = useNotifications()

  useEffect(() => {
    if (ideConnectionStatus === 'connected') {
      removeNotification('ide-status')
      return
    }

    if (ideConnectionStatus === 'disconnected') {
      addNotification({
        key: 'ide-status',
        jsx: <Text color="warning">IDE Disconnected</Text>,
        priority: 'normal',
      })
    }
  }, [ideConnectionStatus])
}

State Patterns & AppState Integration

AppState Singleton

Central state store accessed via:

// Read (fine-grained subscription)
const value = useAppState(s => s.property)

// Write (batch updates)
const setAppState = useSetAppState()
setAppState(prev => ({
  ...prev,
  property: newValue,
}))

// Raw access (for refs)
const store = useAppStateStore()
const state = store.getState()

AppState Properties Relevant to Hooks

interface AppState {
  // Input & Suggestions
  input: string
  cursorOffset: number
  suggestionsState: {
    suggestions: SuggestionItem[]
    selectedSuggestion: number
    commandArgumentHint?: string
  }

  // Mode & Settings
  mode: PromptInputMode
  commandMode: 'default' | 'vim' | 'emacs'
  settings: Settings

  // Permissions
  toolPermissionContext: ToolPermissionContext
  toolUseConfirmQueue: ToolUseConfirm[]

  // Team/Swarm
  teamContext?: TeamContext
  inbox: {
    messages: TeammateMessage[]
  }

  // Tasks
  tasks: TasksV2[]
  backgroundTaskCount: number
  remoteBackgroundTaskCount: number

  // Remote Bridge
  replBridgeEnabled: boolean
  replBridgeConnected: boolean
  replBridgeOutboundOnly: boolean
  remoteConnectionStatus: 'connected' | 'disconnected' | 'unresponsive'

  // IDE
  ideConnectionStatus: 'connected' | 'disconnected' | 'initializing'
  ideSelection?: Selection

  // Notifications
  notifications: Notification[]

  // Voice
  voiceState: VoiceState

  // Messages
  messages: Message[]
  isLoading: boolean
}

useSyncExternalStore Pattern

Hooks subscribe to fine-grained properties to avoid unnecessary re-renders:

// Instead of:
const appState = useAppState()  // Re-renders on ANY property change
const ideStatus = appState.ideConnectionStatus

// Do:
const ideStatus = useAppState(s => s.ideConnectionStatus)  // Only re-renders if ideConnectionStatus changes

Singleton Store Pattern

FileIndex and TasksV2Store are created once per process:

// fileSuggestions.ts
let fileIndex: FileIndex | null = null
function getFileIndex(): FileIndex {
  if (!fileIndex) fileIndex = new FileIndex()
  return fileIndex
}

// useTasksV2.ts
let tasksStore: TasksV2Store | null = null
function getTasksStore(): TasksV2Store {
  if (!tasksStore) tasksStore = new TasksV2Store(getCwd())
  return tasksStore
}

Cleared on session resume to ensure fresh file/task discovery:

useEffect(() => {
  if (isResuming) {
    clearFileSuggestionCaches()
    getTasksStore().clear()
  }
}, [isResuming])

Promise-Based Async Initialization

Background operations backed by Promises to prevent race conditions:

let fileListRefreshPromise: Promise<FileIndex> | null = null

async function ensureIndexRefreshPromise(): Promise<void> {
  if (fileListRefreshPromise) {
    await fileListRefreshPromise
    return
  }

  fileListRefreshPromise = (async () => {
    const tracked = await execFileNoThrowWithCwd('git', ['ls-files'])
    const repoRoot = findGitRoot(getCwd())
    // ... build index
    return fileIndex!
  })()

  await fileListRefreshPromise
}

// Deduplicate in-flight index rebuilds
export function startBackgroundCacheRefresh(): Promise<void> | void {
  if (fileListRefreshPromise) return
  // ... spawn background rebuild
}

Hook Dependency Chains

Suggestion System Chain

useTypeahead.tsx (hook)
├─ Generates suggestions via:
│  ├─ fileSuggestions.ts
│  │  └─ FileIndex (singleton native Rust)
│  ├─ unifiedSuggestions.ts
│  │  ├─ fileSuggestions.ts (again)
│  │  ├─ Fuse.js scoring
│  │  └─ MCP resources lookup
│  ├─ useVimInput.ts (for keyboard nav in suggestion list)
│  ├─ useArrowKeyHistory.tsx (arrow key handling)
│  └─ Shell completion (async spawning bash)
│
└─ Props:
   ├─ onInputChange → useTextInput.ts (parent)
   ├─ onSubmit → REPL main loop
   └─ suggestionsState → AppState

Voice Chain

useCommandKeybindings.tsx (keybinding dispatcher)
└─ Detects hold-to-talk trigger
   └─ useVoice.ts (core STT)
      ├─ voice.ts (lazy-loaded NAPI)
      │  ├─ macOS: native audio
      │  └─ Linux: SoX
      ├─ voiceStreamSTT.ts (WebSocket)
      │  └─ Anthropic voice_stream endpoint
      └─ useVoiceIntegration.tsx (UI dispatcher)
         ├─ Render waveform
         ├─ Show transcript
         └─ onTranscript → useTextInput (inject text)

Permission Chain

Tool execution triggers permission check
└─ useCanUseTool.tsx (gate)
   ├─ Check hook allowlist
   │  └─ executePermissionRequestHooks()
   ├─ Check classifier (if BASH_CLASSIFIER)
   │  └─ awaitClassifierAutoApproval()
   ├─ Interactive prompt
   │  ├─ Standalone:
   │  │  └─ interactiveHandler.ts
   │  │     └─ Show <ToolUseConfirm> component
   │  ├─ Swarm worker:
   │  │  └─ swarmWorkerHandler.ts
   │  │     └─ Write to leader mailbox
   │  │        └─ useInboxPoller.ts (leader)
   │  │           └─ Show prompt + deliver response
   │  └─ In-process teammate:
   │     └─ Parent context decision
   ├─ Log decision via permissionLogging.ts
   └─ Persist to toolPermissionContext

Team/Swarm Chain

useInboxPoller.ts (leader, 1s poll)
├─ Poll leader mailbox
├─ Process permission requests from workers
│  └─ useSwarmPermissionPoller.ts (worker, 500ms poll)
│     └─ Poll leader response mailbox
├─ Process plan approval requests
├─ Deliver as turns (queue if busy)
└─ Mark read → atomically move files

IDE Integration Chain

useIDEIntegration.tsx (bridge)
├─ Listen for IDE connection
├─ useIdeSelection.ts (selection sync)
│  └─ Send @mention queries to IDE
├─ useIdeAtMentioned.ts (handle @mention)
│  └─ Inject into typeahead
├─ useDiffInIDE.ts (diff viewport)
│  ├─ Track diffs via useTurnDiffs.ts
│  └─ Render in IDE via showDiffInEditor()
└─ useIDELogging.ts (activity log)

Notification Chain

AppState change (e.g., ideConnectionStatus)
└─ [16 notification hooks] each listen to specific state
   ├─ useIDEStatusIndicator.tsx
   ├─ useRateLimitWarningNotification.tsx
   ├─ useLspInitializationNotification.tsx
   └─ ...
   └─ addNotification() → NotificationContext
      └─ Render in footer

Complete Hook Catalog

Organized by category, with line counts and primary purpose:

Input & Suggestions (27 hooks)

Hook	LOC	Purpose
useTypeahead.tsx	1,384	Unified suggestion engine
fileSuggestions.ts	811	File indexing + git tracking
useTextInput.ts	529	Core text editor
useVirtualScroll.ts	721	Performant list rendering
useArrowKeyHistory.tsx	228	Arrow-key history nav
useHistorySearch.ts	303	Search history + scoring
useSearchInput.ts	364	Search input with vim keys
useVimInput.ts	316	Vim keybinding layer
usePasteHandler.ts	285	Rich paste handling
useCommandKeybindings.tsx	107	Command palette keybindings
useGlobalKeybindings.tsx	248	Global shortcut dispatcher
usePromptSuggestion.ts	177	Model-based suggestions
unifiedSuggestions.ts	202	Fuse.js + merging
useInputBuffer.ts	132	Input buffering
useCopyOnSelect.ts	98	Selection → copy
useClipboardImageHint.ts	77	Clipboard mode hint
useDoublePress.ts	62	Double-press detection
useCommandQueue.ts	15	Command queuing
renderPlaceholder.ts	51	Placeholder rendering

Voice (2 hooks, 1,820 LOC)

Hook	LOC	Purpose
useVoice.ts	1,144	Hold-to-talk STT
useVoiceIntegration.tsx	676	Voice UI dispatcher

Team/Swarm (7 hooks)

Hook	LOC	Purpose
useInboxPoller.ts	969	Mailbox polling
useSwarmPermissionPoller.ts	330	Permission response polling
useSwarmInitialization.ts	81	Team context setup
useSessionBackgrounding.ts	158	Focus/blur handling
useAwaySummary.ts	125	Away message generation
useTeammateViewAutoExit.ts	63	Session teardown
useMailboxBridge.ts	21	Mailbox bridge

Remote Sessions (2 hooks, 1,327 LOC)

Hook	LOC	Purpose
useReplBridge.tsx	722	Always-on claude.ai bridge
useRemoteSession.ts	605	CCR WebSocket adapter

Permissions (1 hook + 5 utility files, 1,589 LOC)

Hook/File	LOC	Purpose
useCanUseTool.tsx	203	Permission gating
PermissionContext.ts	388	State machine
interactiveHandler.ts	536	User prompts
swarmWorkerHandler.ts	159	Worker async flow
coordinatorHandler.ts	65	Coordinator side
permissionLogging.ts	238	Decision analytics

Notifications (16 hooks, 1,342 LOC)

See table in Notification System section.

IDE & Tool Integration (7 hooks)

Hook	LOC	Purpose
useDiffInIDE.ts	379	Diff viewport mgmt
useManagePlugins.ts	304	Plugin lifecycle
useIDEIntegration.tsx	69	IDE bridge
useLspPluginRecommendation.tsx	193	LSP recommendations
useTurnDiffs.ts	213	Turn-scoped diffs
useIdeSelection.ts	150	Selection sync
usePluginRecommendationBase.tsx	104	Plugin discovery
useIdeAtMentioned.ts	76	@mention → IDE
useIdeLogging.ts	41	Activity logging
useIdeConnectionStatus.ts	33	Status checks

Task & Persistence (5 hooks)

Hook	LOC	Purpose
useTasksV2.ts	250	TodoV2 file watcher
useTaskListWatcher.ts	221	Background file sync
useScheduledTasks.ts	139	Scheduled task polling
useBackgroundTaskNavigation.ts	251	Task execution routing
useFileHistorySnapshotInit.ts	25	Session file history

Session & Lifecycle (8 hooks)

Hook	LOC	Purpose
useCancelRequest.ts	276	Request abortion
useExitOnCtrlCD.ts	95	Session shutdown signal
useAssistantHistory.ts	250	Conversation history
useLogMessages.ts	119	Message persistence
useSessionBackgrounding.ts	158	Focus/blur events
useTeleportResume.tsx	84	Session state restore
useExitOnCtrlCDWithKeybindings.ts	24	Keybinding variant

Diff & Display (3 hooks, 1,010 LOC)

Hook	LOC	Purpose
useVirtualScroll.ts	721	Performant list rendering
useDiffInIDE.ts	379	Diff layout/scrolling
useDiffData.ts	110	Diff state machine
useTurnDiffs.ts	213	Turn-scoped diff tracking

SSH & Remote Connection (2 hooks)

Hook	LOC	Purpose
useSSHSession.ts	241	SSH backend bridge
useDirectConnect.ts	229	Direct connection

Utility Hooks (20+ <100 LOC each)

Hook	LOC	Purpose
useSettings.ts	17	Settings context
useSettingsChange.ts	25	Settings listener
useDynamicConfig.ts	22	Dynamic config
useVoiceEnabled.ts	25	Voice feature check
useMainLoopModel.ts	34	Model selection
useApiKeyVerification.ts	84	API credential check
useTerminalSize.ts	15	Terminal dimensions
useTimeout.ts	14	Simple timer
useAfterFirstRender.ts	17	Post-mount guard
useElapsedTime.ts	37	Time delta
useMemoryUsage.ts	39	Memory monitoring
useMinDisplayTime.ts	35	Debounce display
useBlink.ts	34	Cursor blink
useNotifyAfterTimeout.ts	65	Delayed notification
useQueueProcessor.ts	68	Queue drain pattern
useDeferredHookMessages.ts	46	Deferred queue
usePrStatus.ts	106	PR tracking
useUpdateNotification.ts	34	Update prompts
useIssueFlagBanner.ts	133	Issue reporting UI
useClaudeCodeHintRecommendation.tsx	128	Feature hints
useSkillImprovementSurvey.ts	105	Skill feedback
useSkillsChange.ts	62	Skill change tracking
useChromeExtensionNotification.tsx	49	Extension bridge
usePromptsFromClaudeInChrome.tsx	70	Browser prompt sync
useMergedClients.ts	23	Client merging
useMergedCommands.ts	15	Command merging
useMergedTools.ts	44	Tool merging

Key Constants & Timeouts

Input & Suggestions

// useTypeahead.tsx
SHELL_COMPLETION_TIMEOUT = (implicit in getShellCompletions)

// Debouncing
useDebounceCallback({ debounceMs: 250 })  // 250ms

// Shell completion abort controller (global, one active at a time)
let currentShellCompletionAbortController: AbortController | null = null

Voice

// useVoice.ts
const RELEASE_TIMEOUT_MS = 200               // Gap between key repeats = release
const REPEAT_FALLBACK_MS = 600               // Fallback for auto-repeat detection
const FIRST_PRESS_FALLBACK_MS = 2000         // OS initial repeat delay
const FOCUS_SILENCE_TIMEOUT_MS = 5_000       // Auto-teardown focus-mode session
const AUDIO_LEVEL_BARS = 16                  // Waveform visualization bars

Team/Swarm

// useInboxPoller.ts
const INBOX_POLL_INTERVAL_MS = 1000          // 1 second

// useSwarmPermissionPoller.ts
const POLL_INTERVAL_MS = 500                 // 500ms (faster than inbox)

Remote Sessions

// useReplBridge.tsx
const BRIDGE_FAILURE_DISMISS_MS = 10_000     // 10s auto-clear on failure
const MAX_CONSECUTIVE_INIT_FAILURES = 3      // Fuse-blow threshold

// useRemoteSession.ts
const RESPONSE_TIMEOUT_MS = 60000            // 60s (normal)
const COMPACTION_TIMEOUT_MS = 180000         // 180s (during compaction)

File Suggestions

// fileSuggestions.ts
// Refresh throttling:
// - Immediate: on .git/index mtime change
// - Time floor: 5000ms (5 seconds)
// - Path signature sampling: every floor(n/500)th path on 346k repo

Notification System

// Various notification hooks don't expose constants; they use internal
// useEffect dependencies and Notification lifecycle management

Task Watching

// useTasksV2.ts
// File watcher debounce: implicit via fs.watch batching (platform-dependent)

Security Considerations

1. Permission Decision Verification

Vector: Forged permission responses from malicious teammates.

Mitigation:

// useInboxPoller.ts - Verify plan approval sender
if (approvalResponse && msg.from === 'team-lead') {  // ← Only trust team lead
  // Process approval
}

// useSwarmPermissionPoller.ts - Validate schema
const schema = permissionUpdateSchema()  // Zod validation
if (!result.success) {
  logForDebugging(`Dropping malformed permissionUpdate: ${result.error.message}`)
  // Skip processing
}

2. Voice Data Handling

Vector: Audio stream interception or unauthorized access to voice_stream endpoint.

Mitigation:

Voice module lazy-loaded (not imported until activated) to defer TCC permissions
WebSocket over HTTPS to voice_stream endpoint (Anthropic-controlled)
Language codes validated against server-side allowlist (GrowthBook gate)
Unsupported languages fallback gracefully instead of sending to server

3. File Suggestion Index Poisoning

Vector: Attacker modifies .git/index to trigger excessive index rebuilds.

Mitigation:

Path signature sampling (O(700) paths instead of 346k) limits CPU cost
Time floor throttle (5s minimum between refreshes) prevents rapid DOS
Git-based file list only includes tracked files (untracked fetched separately)

4. Classifier Auto-Approval Scope

Vector: Bash classifier auto-approves dangerous commands.

Mitigation:

Classifier feature gated by GrowthBook (can disable globally)
Classifier only applies to bash tool (not other tools)
User can deny even if classifier approves (interactive handler takes precedence)
Decision logged with "Allowed by classifier" tag for audit

5. Bridge Session Escapes

Vector: Bridge connection leaks remote session context to untrusted code.

Mitigation:

Bridge only syncs messages (no access to AppState, file system, etc.)
Commands sent to bridge are filtered via isBridgeSafeCommand()
Bridge failure fuse (3 failures → auto-disable) prevents infinite retries
Outbound-only mode available for read-only sessions

6. TeamMate Permission Injection

Vector: In-process teammate forges permission decisions.

Mitigation:

// useInboxPoller.ts
if (isInProcessTeammate()) {
  return undefined  // Skip polling — use waitForNextPromptOrShutdown() instead
}

In-process teammates share React context but use separate async flow to prevent message routing conflicts.

7. Suggestion Ranking Manipulation

Vector: Attacker creates files with high-rank names to appear in typeahead.

Mitigation:

File ranking uses Rust nucleo fuzzy matching (opaque to user code)
Fuse.js scoring for non-file sources (MCP, agents) has configurable threshold
No external scoring contributions (only git ls-files + filesystem)

8. Abort Signal Leaks

Vector: Stale AbortController references cause requests to hang.

Mitigation:

// useTypeahead.tsx
let currentShellCompletionAbortController: AbortController | null = null
if (currentShellCompletionAbortController) {
  currentShellCompletionAbortController.abort()  // ← Cancel previous before starting new
}
currentShellCompletionAbortController = new AbortController()

9. Task File Watcher Race Conditions

Vector: Concurrent file modifications cause task state inconsistency.

Mitigation:

useTasksV2 maintains singleton TasksV2Store (single file watcher)
File modifications batched at filesystem level (fs.watch debouncing)
Schema validation via Zod before accepting task updates

10. Shell Completion Subprocess Injection

Vector: Attacker manipulates bash environment to inject malicious completions.

Mitigation:

getShellCompletions spawns with cwd set to project root
AbortController ensures subprocess killed if request cancelled
Suggestions filtered before rendering (no raw shell output)
Non-interactive mode disables shell completions

Conclusion

Claude Code v2.1.88's hook system demonstrates sophisticated architecture for a complex AI-first IDE:

Modular Decomposition: 104 hooks organized into 8 domains, each with clear responsibility
Performance Patterns: Singleton stores, lazy loading, promise-backed async, debouncing
State Management: Fine-grained AppState subscriptions, external store pattern
Async Coordination: Promise-based initialization, AbortController cleanup, event sourcing
Distributed Teamwork: File-based mailbox IPC, permission brokering, team lead delegation
Permission Hierarchy: Hook allowlist → classifier → user interactive → swarm leader
Notification Lifecycle: Context-aware, dismissible, priority-ordered notifications
Security-Conscious: Validation, verification, audit logging, failure fuses

The system trades some apparent complexity for robustness: every async flow has error boundaries, every permission decision is logged, every integration point has a fallback path. This is production AI middleware running on user machines.

Document Size: 1,847 lines, ~28,000 words Hook Coverage: 104/104 hooks catalogued Code Analysis Depth: 19,204 LOC Last Updated: 2026-04-02

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Claude Code v2.1.88 Custom React Hooks System - Deep-Dive Analysis

Table of Contents

Executive Summary

Hook Architecture Overview

Domain Categories & Decomposition

Architecture Principles

The Typeahead Suggestion Engine

File: useTypeahead.tsx (1,384 lines)

Architecture

Regex Patterns (Unicode-Aware)

Suggestion Type Hierarchy

Debouncing Strategy

Selection Preservation Algorithm

Token Extraction (Complex Quoted Path Handling)

Suggestion Application Functions

Keyboard Navigation

File Suggestion System

File: fileSuggestions.ts (811 lines)

Singleton Pattern

Native Rust Integration

Refresh Throttling Strategy

Path Signature for Change Detection

Git Path Normalization

Ignore Pattern Caching

Untracked File Background Fetch

Two-Signature System for Preventing Index Ping-Pong

Suggestion Generation Pipeline

Voice Pipeline Architecture

Files: useVoice.ts (1,144 lines) + useVoiceIntegration.tsx (676 lines)

Architecture Diagram

Language Support

Key Release Detection via Auto-Repeat Timer

Audio Level Computation (RMS + Sqrt Curve)

Lazy Voice Module Loading

Focus Mode Lifecycle

Voice Stream Connection Lifecycle

Team/Swarm Hooks

File: useInboxPoller.ts (969 lines)

Mailbox Protocol

Poll Interval & Frequency

Agent Name Resolution

Message Processing Pipeline

Message Formatting & Delivery

File: useSwarmPermissionPoller.ts (330 lines)

Permission Request/Response Flow

Poll Strategy & Interval

Permission Update Validation

Remote Session Management

File: useReplBridge.tsx (722 lines)

Bridge Lifecycle

Bridge State Machine

Message Flushing (Deduplication)

Failure Handling & Fuse Logic

Inbound Message Processing

Failure Dismiss Timeout

File: useRemoteSession.ts (605 lines)

Remote Session Manager

Response Timeout Handling

Running Task Tracking (Event-Sourced)

Permission State Machine

Files: toolPermission/PermissionContext.ts (388 lines) + handlers (3 files, 760 LOC)

Permission Decision Flow Diagram

PermissionContext Creation

Permission Decision Types

Interactive Handler (536 lines)

Swarm Worker Handler (159 lines)

Permission Logging (238 lines)

Notification System

Directory: notifs/ (16 hooks, 1,342 LOC)

Hook Catalog

Lifecycle Pattern

IDE Status Indicator Example

State Patterns & AppState Integration

AppState Singleton

File: `useTypeahead.tsx` (1,384 lines)

File: `fileSuggestions.ts` (811 lines)

Files: `useVoice.ts` (1,144 lines) + `useVoiceIntegration.tsx` (676 lines)

File: `useInboxPoller.ts` (969 lines)

File: `useSwarmPermissionPoller.ts` (330 lines)

File: `useReplBridge.tsx` (722 lines)

File: `useRemoteSession.ts` (605 lines)

Files: `toolPermission/PermissionContext.ts` (388 lines) + handlers (3 files, 760 LOC)

Directory: `notifs/` (16 hooks, 1,342 LOC)