diff --git a/apps/frontend/src/main/claude-profile/session-utils.ts b/apps/frontend/src/main/claude-profile/session-utils.ts
index fae29e2de9..1f4aedd0e0 100644
--- a/apps/frontend/src/main/claude-profile/session-utils.ts
+++ b/apps/frontend/src/main/claude-profile/session-utils.ts
@@ -6,7 +6,8 @@
  * and can be copied between profiles to enable session continuity after profile switches.
  */
 
-import { existsSync, mkdirSync, copyFileSync, cpSync, unlinkSync } from 'fs';
+import { existsSync } from 'fs';
+import { mkdir, copyFile, cp, unlink } from 'fs/promises';
 import { join, dirname } from 'path';
 import { homedir } from 'os';
 import { isNodeError } from '../utils/type-guards';
@@ -95,12 +96,12 @@ export interface SessionMigrationResult {
  * @param sessionId - The session UUID to migrate
  * @returns Migration result with success status and details
  */
-export function migrateSession(
+export async function migrateSession(
   sourceConfigDir: string,
   targetConfigDir: string,
   cwd: string,
   sessionId: string
-): SessionMigrationResult {
+): Promise<SessionMigrationResult> {
   const result: SessionMigrationResult = {
     success: false,
     sessionId,
@@ -118,13 +119,14 @@ export function migrateSession(
   try {
     // Ensure target directory exists (do this first, before any file operations)
     const targetParentDir = dirname(targetFile);
-    mkdirSync(targetParentDir, { recursive: true });
+    await mkdir(targetParentDir, { recursive: true });
     console.warn('[SessionUtils] Ensured target directory exists:', targetParentDir);
 
     // Attempt to copy the session .jsonl file
     // This will throw if source doesn't exist or target cannot be written
+    // Note: copyFile silently overwrites by default (no COPYFILE_EXCL flag)
     try {
-      copyFileSync(sourceFile, targetFile);
+      await copyFile(sourceFile, targetFile);
       result.filesCopied++;
       console.warn('[SessionUtils] Copied session file:', sourceFile, '->', targetFile);
     } catch (copyError) {
@@ -132,12 +134,6 @@ export function migrateSession(
       if (isNodeError(copyError)) {
         if (copyError.code === 'ENOENT') {
           result.error = `Source session file not found: ${sourceFile}`;
-        } else if (copyError.code === 'EEXIST') {
-          // Target already exists - this is OK, treat as successful skip
-          console.warn('[SessionUtils] Session already exists in target profile, skipping copy');
-          result.success = true;
-          result.filesCopied = 0;
-          return result;
         } else {
           result.error = `Failed to copy session file: ${copyError.message}`;
         }
@@ -153,7 +149,7 @@ export function migrateSession(
     // Attempt to copy the session directory (tool-results) if it exists
     // Use try-catch instead of existsSync to avoid TOCTOU race
     try {
-      cpSync(sourceDir, targetDir, { recursive: true });
+      await cp(sourceDir, targetDir, { recursive: true });
       result.filesCopied++;
       console.warn('[SessionUtils] Copied session directory:', sourceDir, '->', targetDir);
     } catch (dirCopyError) {
@@ -182,7 +178,7 @@ export function migrateSession(
     // Clean up partially migrated session file to enable retry
     // Use try-catch instead of existsSync to avoid TOCTOU race
     try {
-      unlinkSync(targetFile);
+      await unlink(targetFile);
       console.warn('[SessionUtils] Cleaned up partial migration file:', targetFile);
     } catch (cleanupError) {
       // If file doesn't exist during cleanup, that's fine
diff --git a/apps/frontend/src/main/ipc-handlers/terminal-handlers.ts b/apps/frontend/src/main/ipc-handlers/terminal-handlers.ts
index 0bfef37956..5aca822539 100644
--- a/apps/frontend/src/main/ipc-handlers/terminal-handlers.ts
+++ b/apps/frontend/src/main/ipc-handlers/terminal-handlers.ts
@@ -252,6 +252,8 @@ export function registerTerminalHandlers(
             id: string;
             sessionId?: string;
             sessionMigrated?: boolean;
+            isClaudeMode?: boolean;
+            dangerouslySkipPermissions?: boolean;
           }> = [];
 
           // Process each terminal
@@ -273,7 +275,7 @@ export function registerTerminalHandlers(
                 to: targetConfigDir
               });
 
-              const migrationResult = migrateSession(
+              const migrationResult = await migrateSession(
                 sourceConfigDir,
                 targetConfigDir,
                 terminal.cwd,
@@ -284,11 +286,19 @@ export function registerTerminalHandlers(
               debugLog('[terminal-handlers:CLAUDE_PROFILE_SET_ACTIVE] Session migration result:', migrationResult);
             }
 
+            // Store YOLO mode flag server-side for migrated sessions
+            // (consumed by resumeClaudeAsync when the new terminal resumes)
+            if (sessionMigrated && terminal.claudeSessionId && terminal.dangerouslySkipPermissions) {
+              terminalManager.storeMigratedSessionFlag(terminal.claudeSessionId, terminal.dangerouslySkipPermissions);
+            }
+
             // All terminals need refresh (PTY env vars can't be updated)
             terminalsNeedingRefresh.push({
               id: terminal.id,
               sessionId: terminal.claudeSessionId,
-              sessionMigrated
+              sessionMigrated,
+              isClaudeMode: terminal.isClaudeMode,
+              dangerouslySkipPermissions: terminal.dangerouslySkipPermissions
             });
           }
 
@@ -613,9 +623,9 @@ export function registerTerminalHandlers(
 
   ipcMain.on(
     IPC_CHANNELS.TERMINAL_RESUME_CLAUDE,
-    (_, id: string, sessionId?: string) => {
+    (_, id: string, sessionId?: string, options?: { migratedSession?: boolean }) => {
       // Use async version to avoid blocking main process during CLI detection
-      terminalManager.resumeClaudeAsync(id, sessionId).catch((error) => {
+      terminalManager.resumeClaudeAsync(id, sessionId, options).catch((error) => {
         console.warn('[terminal-handlers] Failed to resume Claude:', error);
       });
     }
diff --git a/apps/frontend/src/main/terminal/claude-integration-handler.ts b/apps/frontend/src/main/terminal/claude-integration-handler.ts
index ef4c92b903..3dfa8df899 100644
--- a/apps/frontend/src/main/terminal/claude-integration-handler.ts
+++ b/apps/frontend/src/main/terminal/claude-integration-handler.ts
@@ -1211,7 +1211,10 @@ export function resumeClaude(
       console.warn('[ClaudeIntegration:resumeClaude] sessionId parameter is deprecated and ignored; using claude --continue instead');
     }
 
-    const command = `${pathPrefix}${escapedClaudeCmd} --continue`;
+    // Preserve YOLO mode flag from terminal's stored state
+    const extraFlags = terminal.dangerouslySkipPermissions ? YOLO_MODE_FLAG : '';
+
+    const command = `${pathPrefix}${escapedClaudeCmd} --continue${extraFlags}`;
 
     // Use PtyManager.writeToPty for safer write with error handling
     PtyManager.writeToPty(terminal, `${command}\r`);
@@ -1386,7 +1389,8 @@ export async function invokeClaudeAsync(
 export async function resumeClaudeAsync(
   terminal: TerminalProcess,
   sessionId: string | undefined,
-  getWindow: WindowGetter
+  getWindow: WindowGetter,
+  options?: { migratedSession?: boolean }
 ): Promise<void> {
   // Track terminal state for cleanup on error
   const wasClaudeMode = terminal.isClaudeMode;
@@ -1419,12 +1423,19 @@ export async function resumeClaudeAsync(
     // and we don't want stale IDs persisting through SessionHandler.persistSessionAsync().
     terminal.claudeSessionId = undefined;
 
-    // Deprecation warning for callers still passing sessionId
-    if (sessionId) {
+    // Deprecation warning for callers still passing sessionId (skip for migrated sessions)
+    if (sessionId && !options?.migratedSession) {
       console.warn('[ClaudeIntegration:resumeClaudeAsync] sessionId parameter is deprecated and ignored; using claude --continue instead');
     }
 
-    const command = `${pathPrefix}${escapedClaudeCmd} --continue`;
+    if (options?.migratedSession) {
+      debugLog('[ClaudeIntegration:resumeClaudeAsync] Post-swap resume for terminal:', terminal.id);
+    }
+
+    // Preserve YOLO mode flag from terminal's stored state
+    const extraFlags = terminal.dangerouslySkipPermissions ? YOLO_MODE_FLAG : '';
+
+    const command = `${pathPrefix}${escapedClaudeCmd} --continue${extraFlags}`;
 
     // Use PtyManager.writeToPty for safer write with error handling
     PtyManager.writeToPty(terminal, `${command}\r`);
diff --git a/apps/frontend/src/main/terminal/terminal-manager.ts b/apps/frontend/src/main/terminal/terminal-manager.ts
index a81f6e1e8f..78cd6f3d72 100644
--- a/apps/frontend/src/main/terminal/terminal-manager.ts
+++ b/apps/frontend/src/main/terminal/terminal-manager.ts
@@ -11,7 +11,7 @@ import type {
   TerminalProcess,
   WindowGetter,
   TerminalOperationResult,
-  TerminalProfileChangeInfo
+  TerminalProfileChangeInfo,
 } from './types';
 import * as PtyManager from './pty-manager';
 import * as SessionHandler from './session-handler';
@@ -26,6 +26,8 @@ export class TerminalManager {
   private saveTimer: NodeJS.Timeout | null = null;
   private lastNotifiedRateLimitReset: Map<string, string> = new Map();
   private eventCallbacks: TerminalEventHandler.EventHandlerCallbacks;
+  /** Server-side storage for YOLO mode flags during profile migration (sessionId → flag) */
+  private migratedSessionFlags: Map<string, boolean> = new Map();
 
   constructor(getWindow: WindowGetter) {
     this.getWindow = getWindow;
@@ -114,6 +116,7 @@ export class TerminalManager {
    * Kill all terminal processes
    */
   async killAll(): Promise<void> {
+    this.migratedSessionFlags.clear();
     this.saveTimer = await TerminalLifecycle.destroyAllTerminals(
       this.terminals,
       this.saveTimer
@@ -223,13 +226,36 @@ export class TerminalManager {
   /**
    * Resume Claude in a terminal asynchronously (non-blocking)
    */
-  async resumeClaudeAsync(id: string, sessionId?: string): Promise<void> {
+  async resumeClaudeAsync(id: string, sessionId?: string, options?: { migratedSession?: boolean }): Promise<void> {
     const terminal = this.terminals.get(id);
     if (!terminal) {
+      // Clean up stale migratedSessionFlags if terminal no longer exists
+      if (options?.migratedSession && sessionId) {
+        this.migratedSessionFlags.delete(sessionId);
+      }
       return;
     }
 
-    await ClaudeIntegration.resumeClaudeAsync(terminal, sessionId, this.getWindow);
+    // For migrated sessions, restore YOLO mode from server-side storage
+    // (set during profile change in storeMigratedSessionFlag)
+    if (options?.migratedSession && sessionId) {
+      const storedFlag = this.migratedSessionFlags.get(sessionId);
+      if (storedFlag !== undefined) {
+        terminal.dangerouslySkipPermissions = storedFlag;
+        this.migratedSessionFlags.delete(sessionId);
+      }
+    }
+
+    await ClaudeIntegration.resumeClaudeAsync(terminal, sessionId, this.getWindow, options);
+  }
+
+  /**
+   * Store YOLO mode flag for a session being migrated during profile swap.
+   * Called from the profile change handler before the renderer recreates terminals.
+   * The flag is consumed by resumeClaudeAsync when the new terminal resumes.
+   */
+  storeMigratedSessionFlag(sessionId: string, dangerouslySkipPermissions: boolean): void {
+    this.migratedSessionFlags.set(sessionId, dangerouslySkipPermissions);
   }
 
   /**
@@ -387,7 +413,8 @@ export class TerminalManager {
         projectPath: terminal.projectPath,
         claudeSessionId: terminal.claudeSessionId,
         claudeProfileId: terminal.claudeProfileId,
-        isClaudeMode: terminal.isClaudeMode
+        isClaudeMode: terminal.isClaudeMode,
+        dangerouslySkipPermissions: terminal.dangerouslySkipPermissions
       });
     }
 
diff --git a/apps/frontend/src/main/terminal/types.ts b/apps/frontend/src/main/terminal/types.ts
index d68ca2c12d..0f2956e9a4 100644
--- a/apps/frontend/src/main/terminal/types.ts
+++ b/apps/frontend/src/main/terminal/types.ts
@@ -99,4 +99,5 @@ export interface TerminalProfileChangeInfo {
   claudeSessionId?: string;
   claudeProfileId?: string;
   isClaudeMode: boolean;
+  dangerouslySkipPermissions?: boolean;
 }
diff --git a/apps/frontend/src/preload/api/terminal-api.ts b/apps/frontend/src/preload/api/terminal-api.ts
index 67171091ee..fe09cb0f95 100644
--- a/apps/frontend/src/preload/api/terminal-api.ts
+++ b/apps/frontend/src/preload/api/terminal-api.ts
@@ -47,7 +47,7 @@ export interface TerminalAPI {
     rows?: number
   ) => Promise<IPCResult<import('../../shared/types').TerminalRestoreResult>>;
   clearTerminalSessions: (projectPath: string) => Promise<IPCResult>;
-  resumeClaudeInTerminal: (id: string, sessionId?: string) => void;
+  resumeClaudeInTerminal: (id: string, sessionId?: string, options?: { migratedSession?: boolean }) => void;
   activateDeferredClaudeResume: (id: string) => void;
   getTerminalSessionDates: (projectPath?: string) => Promise<IPCResult<import('../../shared/types').SessionDateInfo[]>>;
   getTerminalSessionsForDate: (
@@ -166,8 +166,8 @@ export const createTerminalAPI = (): TerminalAPI => ({
   clearTerminalSessions: (projectPath: string): Promise<IPCResult> =>
     ipcRenderer.invoke(IPC_CHANNELS.TERMINAL_CLEAR_SESSIONS, projectPath),
 
-  resumeClaudeInTerminal: (id: string, sessionId?: string): void =>
-    ipcRenderer.send(IPC_CHANNELS.TERMINAL_RESUME_CLAUDE, id, sessionId),
+  resumeClaudeInTerminal: (id: string, sessionId?: string, options?: { migratedSession?: boolean }): void =>
+    ipcRenderer.send(IPC_CHANNELS.TERMINAL_RESUME_CLAUDE, id, sessionId, options),
 
   activateDeferredClaudeResume: (id: string): void =>
     ipcRenderer.send(IPC_CHANNELS.TERMINAL_ACTIVATE_DEFERRED_RESUME, id),
diff --git a/apps/frontend/src/renderer/components/terminal/useTerminalEvents.ts b/apps/frontend/src/renderer/components/terminal/useTerminalEvents.ts
index 0fd26af7ef..e5d19a228c 100644
--- a/apps/frontend/src/renderer/components/terminal/useTerminalEvents.ts
+++ b/apps/frontend/src/renderer/components/terminal/useTerminalEvents.ts
@@ -52,10 +52,12 @@ export function useTerminalEvents({
         const store = useTerminalStore.getState();
         store.setTerminalStatus(terminalId, 'exited');
         // Reset Claude mode when terminal exits - the Claude process has ended
-        // Use updateTerminal instead of setClaudeMode to avoid changing status back to 'running'
+        // setTerminalStatus('exited') already sends SHELL_EXITED to XState (which handles
+        // claude_active -> exited transition), so setClaudeMode(false) here only updates Zustand
+        // (its XState guard skips CLAUDE_EXITED since the machine is already in 'exited')
         const terminal = store.getTerminal(terminalId);
         if (terminal?.isClaudeMode) {
-          store.updateTerminal(terminalId, { isClaudeMode: false });
+          store.setClaudeMode(terminalId, false);
         }
         onExitRef.current?.(exitCode);
 
@@ -146,12 +148,12 @@ export function useTerminalEvents({
           return;
         }
         // Reset Claude mode - Claude has exited but terminal is still running
-        // Use updateTerminal to set all Claude-related state at once
+        // Use setClaudeMode which properly sends CLAUDE_EXITED to the XState machine,
+        // then clear residual Claude state separately
+        store.setClaudeMode(terminalId, false);
         store.updateTerminal(terminalId, {
-          isClaudeMode: false,
           isClaudeBusy: undefined,
           claudeSessionId: undefined,
-          status: 'running'  // Terminal is still running, just not in Claude mode
         });
         console.warn('[Terminal] Claude exited, reset mode for terminal:', terminalId);
       }
diff --git a/apps/frontend/src/renderer/hooks/useTerminalProfileChange.ts b/apps/frontend/src/renderer/hooks/useTerminalProfileChange.ts
index 4b7683b7a7..ad709dbad2 100644
--- a/apps/frontend/src/renderer/hooks/useTerminalProfileChange.ts
+++ b/apps/frontend/src/renderer/hooks/useTerminalProfileChange.ts
@@ -1,4 +1,6 @@
 import { useEffect, useCallback, useRef } from 'react';
+import { useTranslation } from 'react-i18next';
+import { toast } from './use-toast';
 import { useTerminalStore } from '../stores/terminal-store';
 import { terminalBufferManager } from '../lib/terminal-buffer-manager';
 import type { TerminalProfileChangedEvent } from '../../shared/types';
@@ -8,16 +10,18 @@ import { debugLog, debugError } from '../../shared/utils/debug-logger';
  * Hook to handle terminal profile change events.
  * When a Claude profile switches, all terminals need to be recreated with the new profile's
  * environment variables. Terminals with active Claude sessions will have their sessions
- * migrated and can be resumed with --resume {sessionId}.
+ * migrated and automatically resumed with --continue.
  */
 export function useTerminalProfileChange(): void {
+  const { t } = useTranslation(['terminal']);
   // Track terminals being recreated to prevent duplicate processing
   const recreatingTerminals = useRef<Set<string>>(new Set());
 
   const recreateTerminal = useCallback(async (
     terminalId: string,
     sessionId?: string,
-    sessionMigrated?: boolean
+    sessionMigrated?: boolean,
+    isClaudeMode?: boolean
   ) => {
     // Prevent duplicate recreation
     if (recreatingTerminals.current.has(terminalId)) {
@@ -101,25 +105,39 @@ export function useTerminalProfileChange(): void {
         newId: newTerminal.id
       });
 
-      // If there was an active Claude session that was migrated, show a message
-      // and set up for potential resume
+      // If there was an active Claude session that was migrated, auto-resume it
       if (sessionId && sessionMigrated) {
-        debugLog('[useTerminalProfileChange] Session migrated, ready for resume:', sessionId);
-        // Store the session ID so the user can resume if desired
+        debugLog('[useTerminalProfileChange] Session migrated, auto-resuming:', sessionId);
+        // Store the session ID for tracking
         store.setClaudeSessionId(newTerminal.id, sessionId);
-        // Set pending resume flag - user can trigger resume from terminal tab
-        store.setPendingClaudeResume(newTerminal.id, true);
-        // Send a message to the terminal about the session
-        window.electronAPI.sendTerminalInput(
+
+        // Auto-resume the Claude session with --continue
+        // YOLO mode (dangerouslySkipPermissions) is preserved server-side by the
+        // main process during migration (storeMigratedSessionFlag), so resumeClaudeAsync
+        // will restore it automatically when migratedSession is true
+        // Note: resumeClaudeInTerminal uses fire-and-forget IPC (ipcRenderer.send).
+        // If resume fails in the main process, the error is logged but no failure event
+        // is emitted back to the renderer. The terminal will show an empty shell prompt.
+        window.electronAPI.resumeClaudeInTerminal(
           newTerminal.id,
-          `# Profile switched. Previous Claude session available.\n# Run: claude --resume ${sessionId}\n`
+          sessionId,
+          { migratedSession: true }
         );
+        debugLog('[useTerminalProfileChange] Resume initiated for terminal:', newTerminal.id);
+      } else if (isClaudeMode && sessionId && !sessionMigrated) {
+        // Session had an active Claude session but migration failed
+        // Notify user that their Claude session was lost
+        debugError('[useTerminalProfileChange] Session migration failed for terminal:', terminalId);
+        toast({
+          title: t('terminal:swap.migrationFailed'),
+          variant: 'destructive',
+        });
       }
 
     } finally {
       recreatingTerminals.current.delete(terminalId);
     }
-  }, []);
+  }, [t]);
 
   useEffect(() => {
     const cleanup = window.electronAPI.onTerminalProfileChanged(async (event: TerminalProfileChangedEvent) => {
@@ -134,7 +152,8 @@ export function useTerminalProfileChange(): void {
         await recreateTerminal(
           terminalInfo.id,
           terminalInfo.sessionId,
-          terminalInfo.sessionMigrated
+          terminalInfo.sessionMigrated,
+          terminalInfo.isClaudeMode
         );
       }
 
diff --git a/apps/frontend/src/renderer/stores/terminal-store.ts b/apps/frontend/src/renderer/stores/terminal-store.ts
index ffdc246992..1764f475bf 100644
--- a/apps/frontend/src/renderer/stores/terminal-store.ts
+++ b/apps/frontend/src/renderer/stores/terminal-store.ts
@@ -1,10 +1,50 @@
 import { create } from 'zustand';
+import { createActor } from 'xstate';
+import type { ActorRefFrom } from 'xstate';
 import { v4 as uuid } from 'uuid';
 import { arrayMove } from '@dnd-kit/sortable';
 import type { TerminalSession, TerminalWorktreeConfig } from '../../shared/types';
+import { terminalMachine, type TerminalEvent } from '@shared/state-machines';
 import { terminalBufferManager } from '../lib/terminal-buffer-manager';
 import { debugLog, debugError } from '../../shared/utils/debug-logger';
 
+type TerminalActor = ActorRefFrom<typeof terminalMachine>;
+
+/**
+ * Module-level Map to store terminal ID -> XState actor mappings.
+ *
+ * DESIGN NOTE: Stored outside Zustand because actors are mutable references
+ * that shouldn't be serialized in state. Similar pattern to xtermCallbacks.
+ */
+const terminalActors = new Map<string, TerminalActor>();
+
+/**
+ * Get or create an XState terminal actor for a given terminal ID.
+ * Actors are lazily created on first access and cached for the terminal's lifetime.
+ */
+export function getOrCreateTerminalActor(terminalId: string): TerminalActor {
+  let actor = terminalActors.get(terminalId);
+  if (!actor) {
+    actor = createActor(terminalMachine);
+    actor.start();
+    terminalActors.set(terminalId, actor);
+    debugLog(`[TerminalStore] Created XState actor for terminal: ${terminalId}`);
+  }
+  return actor;
+}
+
+/**
+ * Send an event to a terminal's XState machine.
+ * Creates the actor if it doesn't exist yet.
+ */
+export function sendTerminalMachineEvent(terminalId: string, event: TerminalEvent): void {
+  const actor = getOrCreateTerminalActor(terminalId);
+  const stateBefore = String(actor.getSnapshot().value);
+  actor.send(event);
+  const stateAfter = String(actor.getSnapshot().value);
+  debugLog(`[TerminalStore] Machine ${terminalId}: ${event.type} (${stateBefore} -> ${stateAfter})`);
+}
+
 /**
  * Module-level Map to store terminal ID -> xterm write callback mappings.
  *
@@ -301,9 +341,15 @@ export const useTerminalStore = create<TerminalState>((set, get) => ({
   },
 
   removeTerminal: (id: string) => {
-    // Clean up buffer manager and output callback
+    // Clean up buffer manager, output callback, and XState actor
     terminalBufferManager.dispose(id);
     xtermCallbacks.delete(id);
+    const actor = terminalActors.get(id);
+    if (actor) {
+      actor.stop();
+      terminalActors.delete(id);
+      debugLog(`[TerminalStore] Cleaned up XState actor for terminal: ${id}`);
+    }
 
     set((state) => {
       const newTerminals = state.terminals.filter((t) => t.id !== id);
@@ -331,6 +377,13 @@ export const useTerminalStore = create<TerminalState>((set, get) => ({
   },
 
   setTerminalStatus: (id: string, status: TerminalStatus) => {
+    // Notify XState machine of lifecycle transitions
+    if (status === 'running') {
+      sendTerminalMachineEvent(id, { type: 'SHELL_READY' });
+    } else if (status === 'exited') {
+      sendTerminalMachineEvent(id, { type: 'SHELL_EXITED' });
+    }
+
     set((state) => ({
       terminals: state.terminals.map((t) =>
         t.id === id ? { ...t, status } : t
@@ -339,13 +392,32 @@ export const useTerminalStore = create<TerminalState>((set, get) => ({
   },
 
   setClaudeMode: (id: string, isClaudeMode: boolean) => {
+    // Send corresponding event to XState machine
+    if (isClaudeMode) {
+      // Ensure machine has transitioned past idle before sending CLAUDE_ACTIVE
+      const actor = getOrCreateTerminalActor(id);
+      if (String(actor.getSnapshot().value) === 'idle') {
+        sendTerminalMachineEvent(id, { type: 'SHELL_READY' });
+      }
+      // Include current claudeSessionId to prevent XState action from overwriting it
+      const terminal = get().terminals.find(t => t.id === id);
+      sendTerminalMachineEvent(id, { type: 'CLAUDE_ACTIVE', claudeSessionId: terminal?.claudeSessionId });
+    } else {
+      // Only send CLAUDE_EXITED if machine is in a state that accepts it
+      const actor = getOrCreateTerminalActor(id);
+      const currentState = String(actor.getSnapshot().value);
+      if (currentState === 'claude_starting' || currentState === 'claude_active') {
+        sendTerminalMachineEvent(id, { type: 'CLAUDE_EXITED' });
+      }
+    }
+
     set((state) => ({
       terminals: state.terminals.map((t) =>
         t.id === id
           ? {
               ...t,
               isClaudeMode,
-              status: isClaudeMode ? 'claude-active' : 'running',
+              status: isClaudeMode ? 'claude-active' : (t.status === 'exited' ? 'exited' : 'running'),
               // Reset busy state and naming flag when leaving Claude mode
               isClaudeBusy: isClaudeMode ? t.isClaudeBusy : undefined,
               claudeNamedOnce: isClaudeMode ? t.claudeNamedOnce : undefined
@@ -356,6 +428,14 @@ export const useTerminalStore = create<TerminalState>((set, get) => ({
   },
 
   setClaudeSessionId: (id: string, sessionId: string) => {
+    // Ensure machine has transitioned past idle before sending CLAUDE_ACTIVE
+    const actor = getOrCreateTerminalActor(id);
+    if (String(actor.getSnapshot().value) === 'idle') {
+      sendTerminalMachineEvent(id, { type: 'SHELL_READY' });
+    }
+    // Send CLAUDE_ACTIVE with session ID to XState machine
+    sendTerminalMachineEvent(id, { type: 'CLAUDE_ACTIVE', claudeSessionId: sessionId });
+
     set((state) => ({
       terminals: state.terminals.map((t) =>
         t.id === id ? { ...t, claudeSessionId: sessionId } : t
@@ -380,6 +460,9 @@ export const useTerminalStore = create<TerminalState>((set, get) => ({
   },
 
   setClaudeBusy: (id: string, isBusy: boolean) => {
+    // Send CLAUDE_BUSY event to XState machine
+    sendTerminalMachineEvent(id, { type: 'CLAUDE_BUSY', isBusy });
+
     set((state) => ({
       terminals: state.terminals.map((t) =>
         t.id === id ? { ...t, isClaudeBusy: isBusy } : t
@@ -388,11 +471,37 @@ export const useTerminalStore = create<TerminalState>((set, get) => ({
   },
 
   setPendingClaudeResume: (id: string, pending: boolean) => {
-    set((state) => ({
-      terminals: state.terminals.map((t) =>
-        t.id === id ? { ...t, pendingClaudeResume: pending } : t
-      ),
-    }));
+    // Send RESUME_REQUESTED or RESUME_COMPLETE to XState machine
+    let shouldUpdateZustand = true;
+
+    if (pending) {
+      const terminal = get().terminals.find(t => t.id === id);
+      if (terminal?.claudeSessionId) {
+        sendTerminalMachineEvent(id, { type: 'RESUME_REQUESTED', claudeSessionId: terminal.claudeSessionId });
+      } else {
+        // No claudeSessionId - can't send RESUME_REQUESTED, so don't set pendingClaudeResume
+        // to avoid XState/Zustand divergence (UI would show pending but machine wouldn't know)
+        debugLog('[terminal-store] setPendingClaudeResume: dropping request for terminal', id, '- no claudeSessionId');
+        shouldUpdateZustand = false;
+      }
+    } else {
+      // Resume cleared - either completed or cancelled
+      const actor = terminalActors.get(id);
+      if (actor && String(actor.getSnapshot().value) === 'pending_resume') {
+        // Include claudeSessionId to prevent XState action from overwriting it to undefined
+        const terminal = get().terminals.find(t => t.id === id);
+        sendTerminalMachineEvent(id, { type: 'RESUME_COMPLETE', claudeSessionId: terminal?.claudeSessionId });
+      }
+    }
+
+    // Only update Zustand state if XState was notified (prevents state divergence)
+    if (shouldUpdateZustand) {
+      set((state) => ({
+        terminals: state.terminals.map((t) =>
+          t.id === id ? { ...t, pendingClaudeResume: pending } : t
+        ),
+      }));
+    }
   },
 
   setClaudeNamedOnce: (id: string, named: boolean) => {
@@ -404,6 +513,18 @@ export const useTerminalStore = create<TerminalState>((set, get) => ({
   },
 
   clearAllTerminals: () => {
+    // Clean up all resources for every terminal
+    const terminals = get().terminals;
+    for (const terminal of terminals) {
+      terminalBufferManager.dispose(terminal.id);
+      xtermCallbacks.delete(terminal.id);
+    }
+
+    // Clean up all XState actors
+    for (const [_id, actor] of terminalActors) {
+      actor.stop();
+    }
+    terminalActors.clear();
     set({ terminals: [], activeTerminalId: null, hasRestoredSessions: false });
   },
 
diff --git a/apps/frontend/src/shared/i18n/locales/en/terminal.json b/apps/frontend/src/shared/i18n/locales/en/terminal.json
index 7d87ea7d8b..d6e4c38eae 100644
--- a/apps/frontend/src/shared/i18n/locales/en/terminal.json
+++ b/apps/frontend/src/shared/i18n/locales/en/terminal.json
@@ -12,6 +12,14 @@
     "terminalTitle": "Auth: {{profileName}}",
     "maxTerminalsReached": "Cannot open auth terminal: maximum terminals reached. Close a terminal first."
   },
+  "swap": {
+    "inProgress": "Switching profile...",
+    "resumingSession": "Resuming Claude session...",
+    "sessionResumed": "Session resumed under new profile",
+    "resumeFailed": "Could not resume session. You can start a new session.",
+    "noSession": "Profile switched. No active session to resume.",
+    "migrationFailed": "Profile switched, but session migration failed. Starting fresh terminal."
+  },
   "worktree": {
     "create": "Worktree",
     "createNew": "New Worktree",
diff --git a/apps/frontend/src/shared/i18n/locales/fr/terminal.json b/apps/frontend/src/shared/i18n/locales/fr/terminal.json
index a13c0ab050..062ce6802c 100644
--- a/apps/frontend/src/shared/i18n/locales/fr/terminal.json
+++ b/apps/frontend/src/shared/i18n/locales/fr/terminal.json
@@ -12,6 +12,14 @@
     "terminalTitle": "Auth: {{profileName}}",
     "maxTerminalsReached": "Impossible d'ouvrir le terminal d'auth: nombre maximum de terminaux atteint. Fermez un terminal d'abord."
   },
+  "swap": {
+    "inProgress": "Changement de profil...",
+    "resumingSession": "Reprise de la session Claude...",
+    "sessionResumed": "Session reprise sous le nouveau profil",
+    "resumeFailed": "Impossible de reprendre la session. Vous pouvez démarrer une nouvelle session.",
+    "noSession": "Profil changé. Aucune session active à reprendre.",
+    "migrationFailed": "Profil changé, mais la migration de session a échoué. Démarrage d'un nouveau terminal."
+  },
   "worktree": {
     "create": "Worktree",
     "createNew": "Nouveau Worktree",
diff --git a/apps/frontend/src/shared/state-machines/__tests__/terminal-machine.test.ts b/apps/frontend/src/shared/state-machines/__tests__/terminal-machine.test.ts
new file mode 100644
index 0000000000..d7cc63416b
--- /dev/null
+++ b/apps/frontend/src/shared/state-machines/__tests__/terminal-machine.test.ts
@@ -0,0 +1,582 @@
+import { describe, it, expect } from 'vitest';
+import { createActor } from 'xstate';
+import { terminalMachine, type TerminalEvent, type TerminalContext } from '../terminal-machine';
+
+/**
+ * Helper to run a sequence of events and get the final snapshot.
+ * Optionally starts from a restored state with given context.
+ */
+function runEvents(
+  events: TerminalEvent[],
+  initialState?: string,
+  initialContext?: Partial<TerminalContext>
+) {
+  const actor = initialState
+    ? createActor(terminalMachine, {
+        snapshot: terminalMachine.resolveState({
+          value: initialState,
+          context: {
+            claudeSessionId: undefined,
+            profileId: undefined,
+            swapTargetProfileId: undefined,
+            swapPhase: undefined,
+            isBusy: false,
+            error: undefined,
+            ...initialContext,
+          },
+        }),
+      })
+    : createActor(terminalMachine);
+  actor.start();
+
+  for (const event of events) {
+    actor.send(event);
+  }
+
+  const snapshot = actor.getSnapshot();
+  actor.stop();
+  return snapshot;
+}
+
+describe('terminalMachine', () => {
+  describe('initial state', () => {
+    it('should start in idle state', () => {
+      const actor = createActor(terminalMachine);
+      actor.start();
+      expect(actor.getSnapshot().value).toBe('idle');
+      actor.stop();
+    });
+
+    it('should have default context initially', () => {
+      const actor = createActor(terminalMachine);
+      actor.start();
+      const { context } = actor.getSnapshot();
+      expect(context.claudeSessionId).toBeUndefined();
+      expect(context.profileId).toBeUndefined();
+      expect(context.swapTargetProfileId).toBeUndefined();
+      expect(context.swapPhase).toBeUndefined();
+      expect(context.isBusy).toBe(false);
+      expect(context.error).toBeUndefined();
+      actor.stop();
+    });
+  });
+
+  describe('happy path: idle → shell_ready → claude_active → exited', () => {
+    it('should transition from idle to shell_ready', () => {
+      const snapshot = runEvents([{ type: 'SHELL_READY' }]);
+      expect(snapshot.value).toBe('shell_ready');
+    });
+
+    it('should transition from shell_ready to claude_starting', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+      ]);
+      expect(snapshot.value).toBe('claude_starting');
+      expect(snapshot.context.profileId).toBe('profile-1');
+    });
+
+    it('should transition from shell_ready directly to claude_active on CLAUDE_ACTIVE', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-direct' },
+      ]);
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('session-direct');
+    });
+
+    it('should transition from claude_starting to claude_active', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+      ]);
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('session-1');
+    });
+
+    it('should transition from claude_active to shell_ready on CLAUDE_EXITED', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'CLAUDE_EXITED' },
+      ]);
+      expect(snapshot.value).toBe('shell_ready');
+      expect(snapshot.context.claudeSessionId).toBeUndefined();
+      expect(snapshot.context.isBusy).toBe(false);
+    });
+
+    it('should transition to exited on SHELL_EXITED from claude_active', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'SHELL_EXITED', exitCode: 0 },
+      ]);
+      expect(snapshot.value).toBe('exited');
+      expect(snapshot.context.claudeSessionId).toBeUndefined();
+    });
+
+    it('should complete full lifecycle: idle → shell_ready → claude_active → exited', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'SHELL_EXITED' },
+      ]);
+      expect(snapshot.value).toBe('exited');
+    });
+  });
+
+  describe('swap flow: claude_active → swapping → claude_active', () => {
+    const toClaudeActive: TerminalEvent[] = [
+      { type: 'SHELL_READY' },
+      { type: 'CLAUDE_START', profileId: 'profile-1' },
+      { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+    ];
+
+    it('should transition to swapping on SWAP_INITIATED with active session', () => {
+      const snapshot = runEvents([
+        ...toClaudeActive,
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+      ]);
+      expect(snapshot.value).toBe('swapping');
+      expect(snapshot.context.swapTargetProfileId).toBe('profile-2');
+      expect(snapshot.context.swapPhase).toBe('capturing');
+    });
+
+    it('should progress through swap phases', () => {
+      const snapshot = runEvents([
+        ...toClaudeActive,
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+        { type: 'SWAP_SESSION_CAPTURED', claudeSessionId: 'captured-session' },
+      ]);
+      expect(snapshot.value).toBe('swapping');
+      expect(snapshot.context.swapPhase).toBe('migrating');
+      expect(snapshot.context.claudeSessionId).toBe('captured-session');
+    });
+
+    it('should progress to recreating phase', () => {
+      const snapshot = runEvents([
+        ...toClaudeActive,
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+        { type: 'SWAP_SESSION_CAPTURED', claudeSessionId: 'captured-session' },
+        { type: 'SWAP_MIGRATED' },
+      ]);
+      expect(snapshot.context.swapPhase).toBe('recreating');
+    });
+
+    it('should progress to resuming phase', () => {
+      const snapshot = runEvents([
+        ...toClaudeActive,
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+        { type: 'SWAP_SESSION_CAPTURED', claudeSessionId: 'captured-session' },
+        { type: 'SWAP_MIGRATED' },
+        { type: 'SWAP_TERMINAL_RECREATED' },
+      ]);
+      expect(snapshot.context.swapPhase).toBe('resuming');
+    });
+
+    it('should return to claude_active after successful swap', () => {
+      const snapshot = runEvents([
+        ...toClaudeActive,
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+        { type: 'SWAP_SESSION_CAPTURED', claudeSessionId: 'captured-session' },
+        { type: 'SWAP_MIGRATED' },
+        { type: 'SWAP_TERMINAL_RECREATED' },
+        {
+          type: 'SWAP_RESUME_COMPLETE',
+          claudeSessionId: 'new-session',
+          profileId: 'profile-2',
+        },
+      ]);
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('new-session');
+      expect(snapshot.context.profileId).toBe('profile-2');
+      expect(snapshot.context.swapTargetProfileId).toBeUndefined();
+      expect(snapshot.context.swapPhase).toBeUndefined();
+      expect(snapshot.context.isBusy).toBe(false);
+      expect(snapshot.context.error).toBeUndefined();
+    });
+  });
+
+  describe('failed swap: swapping → shell_ready with error', () => {
+    const toSwapping: TerminalEvent[] = [
+      { type: 'SHELL_READY' },
+      { type: 'CLAUDE_START', profileId: 'profile-1' },
+      { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+      { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+    ];
+
+    it('should transition to shell_ready on SWAP_FAILED', () => {
+      const snapshot = runEvents([
+        ...toSwapping,
+        { type: 'SWAP_FAILED', error: 'Swap error' },
+      ]);
+      expect(snapshot.value).toBe('shell_ready');
+      expect(snapshot.context.error).toBe('Swap error');
+      expect(snapshot.context.swapTargetProfileId).toBeUndefined();
+      expect(snapshot.context.swapPhase).toBeUndefined();
+    });
+
+    it('should transition to exited on SHELL_EXITED during swap', () => {
+      const snapshot = runEvents([
+        ...toSwapping,
+        { type: 'SHELL_EXITED', exitCode: 1 },
+      ]);
+      expect(snapshot.value).toBe('exited');
+      expect(snapshot.context.swapTargetProfileId).toBeUndefined();
+      expect(snapshot.context.swapPhase).toBeUndefined();
+      expect(snapshot.context.claudeSessionId).toBeUndefined();
+    });
+  });
+
+  describe('deferred resume: pending_resume → claude_active', () => {
+    it('should transition from shell_ready to pending_resume on RESUME_REQUESTED', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'RESUME_REQUESTED', claudeSessionId: 'session-1' },
+      ]);
+      expect(snapshot.value).toBe('pending_resume');
+      expect(snapshot.context.claudeSessionId).toBe('session-1');
+    });
+
+    it('should transition from claude_active to pending_resume on RESUME_REQUESTED', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'RESUME_REQUESTED', claudeSessionId: 'session-2' },
+      ]);
+      expect(snapshot.value).toBe('pending_resume');
+      expect(snapshot.context.claudeSessionId).toBe('session-2');
+    });
+
+    it('should transition to claude_active on RESUME_COMPLETE', () => {
+      const snapshot = runEvents(
+        [{ type: 'RESUME_COMPLETE', claudeSessionId: 'resumed-session' }],
+        'pending_resume',
+        { claudeSessionId: 'old-session', profileId: 'profile-1' }
+      );
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('resumed-session');
+    });
+
+    it('should transition to shell_ready on RESUME_FAILED', () => {
+      const snapshot = runEvents(
+        [{ type: 'RESUME_FAILED', error: 'Resume failed' }],
+        'pending_resume',
+        { claudeSessionId: 'old-session', profileId: 'profile-1' }
+      );
+      expect(snapshot.value).toBe('shell_ready');
+      expect(snapshot.context.error).toBe('Resume failed');
+      expect(snapshot.context.claudeSessionId).toBeUndefined();
+    });
+
+    it('should transition to claude_active on CLAUDE_ACTIVE (race condition)', () => {
+      const snapshot = runEvents(
+        [{ type: 'CLAUDE_ACTIVE', claudeSessionId: 'race-session' }],
+        'pending_resume',
+        { claudeSessionId: 'old-session', profileId: 'profile-1' }
+      );
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('race-session');
+    });
+
+    it('should transition to exited on SHELL_EXITED from pending_resume', () => {
+      const snapshot = runEvents(
+        [{ type: 'SHELL_EXITED' }],
+        'pending_resume'
+      );
+      expect(snapshot.value).toBe('exited');
+    });
+
+    it('should reset from pending_resume', () => {
+      const snapshot = runEvents(
+        [{ type: 'RESET' }],
+        'pending_resume',
+        { claudeSessionId: 'session-1', profileId: 'profile-1' }
+      );
+      expect(snapshot.value).toBe('idle');
+      expect(snapshot.context.claudeSessionId).toBeUndefined();
+      expect(snapshot.context.profileId).toBeUndefined();
+    });
+  });
+
+  describe('invalid transitions rejected', () => {
+    it('should not allow SWAP_INITIATED from idle', () => {
+      const snapshot = runEvents([
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+      ]);
+      expect(snapshot.value).toBe('idle');
+    });
+
+    it('should not allow SWAP_INITIATED from shell_ready', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+      ]);
+      expect(snapshot.value).toBe('shell_ready');
+    });
+
+    it('should not allow CLAUDE_START from idle', () => {
+      const snapshot = runEvents([
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+      ]);
+      expect(snapshot.value).toBe('idle');
+    });
+
+    it('should not allow CLAUDE_ACTIVE from idle', () => {
+      const snapshot = runEvents([
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+      ]);
+      expect(snapshot.value).toBe('idle');
+    });
+
+    it('should not allow SWAP_INITIATED from claude_starting', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'SWAP_INITIATED', targetProfileId: 'profile-2' },
+      ]);
+      expect(snapshot.value).toBe('claude_starting');
+    });
+
+    it('should not allow RESUME_COMPLETE from claude_active', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'RESUME_COMPLETE', claudeSessionId: 'session-2' },
+      ]);
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('session-1');
+    });
+  });
+
+  describe('CLAUDE_ACTIVE self-transition in claude_active', () => {
+    it('should update claudeSessionId via self-transition', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_ACTIVE' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'late-session' },
+      ]);
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('late-session');
+    });
+  });
+
+  describe('context mutations', () => {
+    it('should set profileId on CLAUDE_START', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'my-profile' },
+      ]);
+      expect(snapshot.context.profileId).toBe('my-profile');
+    });
+
+    it('should set claudeSessionId on CLAUDE_ACTIVE', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-abc' },
+      ]);
+      expect(snapshot.context.claudeSessionId).toBe('session-abc');
+    });
+
+    it('should set isBusy on CLAUDE_BUSY', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'CLAUDE_BUSY', isBusy: true },
+      ]);
+      expect(snapshot.context.isBusy).toBe(true);
+    });
+
+    it('should unset isBusy on CLAUDE_BUSY false', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'CLAUDE_BUSY', isBusy: true },
+        { type: 'CLAUDE_BUSY', isBusy: false },
+      ]);
+      expect(snapshot.context.isBusy).toBe(false);
+    });
+
+    it('should clear error on CLAUDE_START', () => {
+      const snapshot = runEvents(
+        [{ type: 'CLAUDE_START', profileId: 'profile-1' }],
+        'shell_ready',
+        { error: 'previous error' }
+      );
+      expect(snapshot.context.error).toBeUndefined();
+    });
+
+    it('should set error on CLAUDE_EXITED with error', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_EXITED', error: 'crash' },
+      ]);
+      expect(snapshot.value).toBe('shell_ready');
+      expect(snapshot.context.error).toBe('crash');
+    });
+
+    it('should clear session on CLAUDE_EXITED', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'CLAUDE_EXITED' },
+      ]);
+      expect(snapshot.context.claudeSessionId).toBeUndefined();
+      expect(snapshot.context.isBusy).toBe(false);
+    });
+
+    it('should set error on CLAUDE_EXITED with error from claude_active', () => {
+      const snapshot = runEvents([
+        { type: 'SHELL_READY' },
+        { type: 'CLAUDE_START', profileId: 'profile-1' },
+        { type: 'CLAUDE_ACTIVE', claudeSessionId: 'session-1' },
+        { type: 'CLAUDE_EXITED', error: 'crash while active' },
+      ]);
+      expect(snapshot.value).toBe('shell_ready');
+      expect(snapshot.context.error).toBe('crash while active');
+      expect(snapshot.context.claudeSessionId).toBeUndefined();
+    });
+
+    it('should clear error on SHELL_READY from exited', () => {
+      const snapshot = runEvents(
+        [{ type: 'SHELL_READY' }],
+        'exited',
+        { error: 'old error' }
+      );
+      expect(snapshot.value).toBe('shell_ready');
+      expect(snapshot.context.error).toBeUndefined();
+    });
+  });
+
+  describe('guard conditions', () => {
+    it('should not allow SWAP_INITIATED without active session', () => {
+      const snapshot = runEvents(
+        [{ type: 'SWAP_INITIATED', targetProfileId: 'profile-2' }],
+        'claude_active',
+        { claudeSessionId: undefined }
+      );
+      expect(snapshot.value).toBe('claude_active');
+    });
+
+    it('should allow SWAP_INITIATED with active session', () => {
+      const snapshot = runEvents(
+        [{ type: 'SWAP_INITIATED', targetProfileId: 'profile-2' }],
+        'claude_active',
+        { claudeSessionId: 'session-1' }
+      );
+      expect(snapshot.value).toBe('swapping');
+    });
+  });
+
+  describe('RESET from all states', () => {
+    const states = [
+      'idle',
+      'shell_ready',
+      'claude_starting',
+      'claude_active',
+      'swapping',
+      'pending_resume',
+      'exited',
+    ];
+
+    for (const state of states) {
+      it(`should reset to idle from ${state}`, () => {
+        const snapshot = runEvents(
+          [{ type: 'RESET' }],
+          state,
+          {
+            claudeSessionId: 'session-1',
+            profileId: 'profile-1',
+            isBusy: true,
+            error: 'err',
+            swapTargetProfileId: 'profile-2',
+            swapPhase: 'migrating'
+          }
+        );
+        expect(snapshot.value).toBe('idle');
+        expect(snapshot.context.claudeSessionId).toBeUndefined();
+        expect(snapshot.context.profileId).toBeUndefined();
+        expect(snapshot.context.isBusy).toBe(false);
+        expect(snapshot.context.error).toBeUndefined();
+        expect(snapshot.context.swapTargetProfileId).toBeUndefined();
+        expect(snapshot.context.swapPhase).toBeUndefined();
+      });
+    }
+  });
+
+  describe('state restoration from snapshot', () => {
+    it('should restore claude_active state with context', () => {
+      const actor = createActor(terminalMachine, {
+        snapshot: terminalMachine.resolveState({
+          value: 'claude_active',
+          context: {
+            claudeSessionId: 'restored-session',
+            profileId: 'restored-profile',
+            swapTargetProfileId: undefined,
+            swapPhase: undefined,
+            isBusy: true,
+            error: undefined,
+          },
+        }),
+      });
+      actor.start();
+      const snapshot = actor.getSnapshot();
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('restored-session');
+      expect(snapshot.context.profileId).toBe('restored-profile');
+      expect(snapshot.context.isBusy).toBe(true);
+      actor.stop();
+    });
+
+    it('should restore swapping state and complete swap', () => {
+      const snapshot = runEvents(
+        [
+          {
+            type: 'SWAP_RESUME_COMPLETE',
+            claudeSessionId: 'new-session',
+            profileId: 'profile-2',
+          },
+        ],
+        'swapping',
+        {
+          claudeSessionId: 'old-session',
+          profileId: 'profile-1',
+          swapTargetProfileId: 'profile-2',
+          swapPhase: 'resuming',
+        }
+      );
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.profileId).toBe('profile-2');
+      expect(snapshot.context.claudeSessionId).toBe('new-session');
+    });
+
+    it('should restore pending_resume and complete resume', () => {
+      const snapshot = runEvents(
+        [{ type: 'RESUME_COMPLETE', claudeSessionId: 'resumed-session' }],
+        'pending_resume',
+        { claudeSessionId: 'stale-session', profileId: 'profile-1' }
+      );
+      expect(snapshot.value).toBe('claude_active');
+      expect(snapshot.context.claudeSessionId).toBe('resumed-session');
+    });
+
+    it('should restore exited state and restart', () => {
+      const snapshot = runEvents(
+        [{ type: 'SHELL_READY' }],
+        'exited'
+      );
+      expect(snapshot.value).toBe('shell_ready');
+    });
+  });
+});
diff --git a/apps/frontend/src/shared/state-machines/index.ts b/apps/frontend/src/shared/state-machines/index.ts
index 68cd1f3abb..a2f8afed76 100644
--- a/apps/frontend/src/shared/state-machines/index.ts
+++ b/apps/frontend/src/shared/state-machines/index.ts
@@ -7,3 +7,6 @@ export {
   mapStateToLegacy,
 } from './task-state-utils';
 export type { TaskStateName } from './task-state-utils';
+
+export { terminalMachine } from './terminal-machine';
+export type { TerminalContext, TerminalEvent } from './terminal-machine';
diff --git a/apps/frontend/src/shared/state-machines/terminal-machine.ts b/apps/frontend/src/shared/state-machines/terminal-machine.ts
new file mode 100644
index 0000000000..4a990faed7
--- /dev/null
+++ b/apps/frontend/src/shared/state-machines/terminal-machine.ts
@@ -0,0 +1,227 @@
+import { assign, createMachine } from 'xstate';
+
+/**
+ * Terminal lifecycle state machine context.
+ *
+ * Tracks Claude Code session state, profile swap progress,
+ * and error information for a single terminal instance.
+ */
+export interface TerminalContext {
+  claudeSessionId?: string;
+  profileId?: string;
+  swapTargetProfileId?: string;
+  swapPhase?: 'capturing' | 'migrating' | 'recreating' | 'resuming';
+  isBusy: boolean;
+  error?: string;
+}
+
+/**
+ * Discriminated union of all terminal lifecycle events.
+ */
+export type TerminalEvent =
+  | { type: 'SHELL_READY' }
+  | { type: 'CLAUDE_START'; profileId: string }
+  | { type: 'CLAUDE_ACTIVE'; claudeSessionId?: string }
+  | { type: 'CLAUDE_BUSY'; isBusy: boolean }
+  | { type: 'CLAUDE_EXITED'; exitCode?: number; error?: string }
+  | { type: 'SWAP_INITIATED'; targetProfileId: string }
+  | { type: 'SWAP_SESSION_CAPTURED'; claudeSessionId: string }
+  | { type: 'SWAP_MIGRATED' }
+  | { type: 'SWAP_TERMINAL_RECREATED' }
+  | { type: 'SWAP_RESUME_COMPLETE'; claudeSessionId?: string; profileId: string }
+  | { type: 'SWAP_FAILED'; error: string }
+  | { type: 'RESUME_REQUESTED'; claudeSessionId: string }
+  | { type: 'RESUME_COMPLETE'; claudeSessionId?: string }
+  | { type: 'RESUME_FAILED'; error: string }
+  | { type: 'SHELL_EXITED'; exitCode?: number; signal?: string }
+  | { type: 'RESET' };
+
+export const terminalMachine = createMachine(
+  {
+    id: 'terminal',
+    initial: 'idle',
+    types: {} as {
+      context: TerminalContext;
+      events: TerminalEvent;
+    },
+    context: {
+      claudeSessionId: undefined,
+      profileId: undefined,
+      swapTargetProfileId: undefined,
+      swapPhase: undefined,
+      isBusy: false,
+      error: undefined,
+    },
+    states: {
+      idle: {
+        on: {
+          SHELL_READY: 'shell_ready',
+          RESET: { target: 'idle', actions: 'resetContext' },
+        },
+      },
+      shell_ready: {
+        on: {
+          CLAUDE_START: { target: 'claude_starting', actions: 'setProfileId' },
+          CLAUDE_ACTIVE: { target: 'claude_active', actions: 'setClaudeSessionId' },
+          RESUME_REQUESTED: { target: 'pending_resume', actions: 'setClaudeSessionId' },
+          SHELL_EXITED: { target: 'exited', actions: 'clearSession' },
+          RESET: { target: 'idle', actions: 'resetContext' },
+        },
+      },
+      claude_starting: {
+        on: {
+          CLAUDE_ACTIVE: { target: 'claude_active', actions: 'setClaudeSessionId' },
+          CLAUDE_BUSY: { actions: 'setBusy' },
+          CLAUDE_EXITED: { target: 'shell_ready', actions: ['setError', 'clearSession'] },
+          SHELL_EXITED: { target: 'exited', actions: 'clearSession' },
+          RESET: { target: 'idle', actions: 'resetContext' },
+        },
+      },
+      claude_active: {
+        on: {
+          CLAUDE_ACTIVE: { actions: 'updateClaudeSessionId' },
+          CLAUDE_BUSY: { actions: 'setBusy' },
+          CLAUDE_EXITED: { target: 'shell_ready', actions: ['setError', 'clearSession'] },
+          SWAP_INITIATED: {
+            target: 'swapping',
+            guard: 'hasActiveSession',
+            actions: 'setSwapTarget',
+          },
+          RESUME_REQUESTED: { target: 'pending_resume', actions: 'setClaudeSessionId' },
+          SHELL_EXITED: { target: 'exited', actions: 'clearSession' },
+          RESET: { target: 'idle', actions: 'resetContext' },
+        },
+      },
+      swapping: {
+        on: {
+          SWAP_SESSION_CAPTURED: {
+            guard: 'isCapturingPhase',
+            actions: ['setCapturedSession', 'setSwapPhaseMigrating'],
+          },
+          SWAP_MIGRATED: {
+            guard: 'isMigratingPhase',
+            actions: 'setSwapPhaseRecreating',
+          },
+          SWAP_TERMINAL_RECREATED: {
+            guard: 'isRecreatingPhase',
+            actions: 'setSwapPhaseResuming',
+          },
+          SWAP_RESUME_COMPLETE: {
+            target: 'claude_active',
+            guard: 'isResumingPhase',
+            actions: 'applySwapComplete',
+          },
+          SWAP_FAILED: {
+            target: 'shell_ready',
+            actions: ['setError', 'clearSwapState'],
+          },
+          SHELL_EXITED: { target: 'exited', actions: ['clearSession', 'clearSwapState'] },
+          RESET: { target: 'idle', actions: 'resetContext' },
+        },
+      },
+      pending_resume: {
+        on: {
+          CLAUDE_ACTIVE: { target: 'claude_active', actions: 'setClaudeSessionId' },
+          CLAUDE_BUSY: { actions: 'setBusy' },
+          RESUME_COMPLETE: { target: 'claude_active', actions: 'setClaudeSessionId' },
+          RESUME_FAILED: { target: 'shell_ready', actions: ['setError', 'clearSession'] },
+          SHELL_EXITED: { target: 'exited', actions: 'clearSession' },
+          RESET: { target: 'idle', actions: 'resetContext' },
+        },
+      },
+      exited: {
+        on: {
+          SHELL_READY: { target: 'shell_ready', actions: 'clearError' },
+          RESET: { target: 'idle', actions: 'resetContext' },
+        },
+      },
+    },
+  },
+  {
+    guards: {
+      hasActiveSession: ({ context }) => context.claudeSessionId !== undefined,
+      isCapturingPhase: ({ context }) => context.swapPhase === 'capturing',
+      isMigratingPhase: ({ context }) => context.swapPhase === 'migrating',
+      isRecreatingPhase: ({ context }) => context.swapPhase === 'recreating',
+      isResumingPhase: ({ context }) => context.swapPhase === 'resuming',
+    },
+    actions: {
+      setProfileId: assign({
+        profileId: ({ event }) =>
+          event.type === 'CLAUDE_START' ? event.profileId : undefined,
+        error: () => undefined,
+      }),
+      setClaudeSessionId: assign({
+        claudeSessionId: ({ event }) => {
+          if (event.type === 'CLAUDE_ACTIVE') return event.claudeSessionId;
+          if (event.type === 'RESUME_COMPLETE') return event.claudeSessionId;
+          if (event.type === 'RESUME_REQUESTED') return event.claudeSessionId;
+          return undefined;
+        },
+        // Clear isBusy when entering claude_active from another state
+        isBusy: () => false,
+        error: () => undefined,
+      }),
+      // Self-transition action for CLAUDE_ACTIVE within claude_active state:
+      // Updates sessionId but preserves isBusy (avoids resetting busy indicator
+      // when the session ID is refreshed without a state change)
+      updateClaudeSessionId: assign({
+        claudeSessionId: ({ event }) =>
+          event.type === 'CLAUDE_ACTIVE' ? event.claudeSessionId : undefined,
+        error: () => undefined,
+      }),
+      setBusy: assign({
+        isBusy: ({ event }) =>
+          event.type === 'CLAUDE_BUSY' ? event.isBusy : false,
+      }),
+      setError: assign({
+        error: ({ event }) => {
+          if (event.type === 'CLAUDE_EXITED') return event.error;
+          if (event.type === 'SWAP_FAILED') return event.error;
+          if (event.type === 'RESUME_FAILED') return event.error;
+          return undefined;
+        },
+      }),
+      clearError: assign({ error: () => undefined }),
+      clearSession: assign({
+        claudeSessionId: () => undefined,
+        isBusy: () => false,
+      }),
+      setSwapTarget: assign({
+        swapTargetProfileId: ({ event }) =>
+          event.type === 'SWAP_INITIATED' ? event.targetProfileId : undefined,
+        swapPhase: () => 'capturing' as const,
+        error: () => undefined,
+      }),
+      setCapturedSession: assign({
+        claudeSessionId: ({ event }) =>
+          event.type === 'SWAP_SESSION_CAPTURED' ? event.claudeSessionId : undefined,
+      }),
+      setSwapPhaseMigrating: assign({ swapPhase: () => 'migrating' as const }),
+      setSwapPhaseRecreating: assign({ swapPhase: () => 'recreating' as const }),
+      setSwapPhaseResuming: assign({ swapPhase: () => 'resuming' as const }),
+      applySwapComplete: assign({
+        claudeSessionId: ({ event }) =>
+          event.type === 'SWAP_RESUME_COMPLETE' ? event.claudeSessionId : undefined,
+        profileId: ({ event }) =>
+          event.type === 'SWAP_RESUME_COMPLETE' ? event.profileId : undefined,
+        swapTargetProfileId: () => undefined,
+        swapPhase: () => undefined,
+        isBusy: () => false,
+        error: () => undefined,
+      }),
+      clearSwapState: assign({
+        swapTargetProfileId: () => undefined,
+        swapPhase: () => undefined,
+      }),
+      resetContext: assign({
+        claudeSessionId: () => undefined,
+        profileId: () => undefined,
+        swapTargetProfileId: () => undefined,
+        swapPhase: () => undefined,
+        isBusy: () => false,
+        error: () => undefined,
+      }),
+    },
+  }
+);
diff --git a/apps/frontend/src/shared/types/agent.ts b/apps/frontend/src/shared/types/agent.ts
index 2fb39902b4..e4448450bd 100644
--- a/apps/frontend/src/shared/types/agent.ts
+++ b/apps/frontend/src/shared/types/agent.ts
@@ -255,6 +255,10 @@ export interface TerminalProfileChangedEvent {
     sessionId?: string;
     /** Whether the session was successfully migrated to new profile */
     sessionMigrated?: boolean;
+    /** Whether the terminal was in Claude mode (had an active Claude session) */
+    isClaudeMode?: boolean;
+    /** Whether Claude was invoked with --dangerously-skip-permissions (YOLO mode) */
+    dangerouslySkipPermissions?: boolean;
   }>;
 }
 
diff --git a/apps/frontend/src/shared/types/ipc.ts b/apps/frontend/src/shared/types/ipc.ts
index b1fc2c4b63..82168ffa56 100644
--- a/apps/frontend/src/shared/types/ipc.ts
+++ b/apps/frontend/src/shared/types/ipc.ts
@@ -252,7 +252,7 @@ export interface ElectronAPI {
   getTerminalSessions: (projectPath: string) => Promise<IPCResult<TerminalSession[]>>;
   restoreTerminalSession: (session: TerminalSession, cols?: number, rows?: number) => Promise<IPCResult<TerminalRestoreResult>>;
   clearTerminalSessions: (projectPath: string) => Promise<IPCResult>;
-  resumeClaudeInTerminal: (id: string, sessionId?: string) => void;
+  resumeClaudeInTerminal: (id: string, sessionId?: string, options?: { migratedSession?: boolean }) => void;
   activateDeferredClaudeResume: (id: string) => void;
   getTerminalSessionDates: (projectPath?: string) => Promise<IPCResult<SessionDateInfo[]>>;
   getTerminalSessionsForDate: (date: string, projectPath: string) => Promise<IPCResult<TerminalSession[]>>;