Fix: Restore views properly, model selection for commit and pr and speed up some cli models with session resume (#801)

* Changes from fix/restoring-view

* feat: Add resume query safety checks and optimize store selectors

* feat: Improve session management and model normalization

* refactor: Extract prompt building logic and handle file path parsing for renames

apps/ui/src/components/views/agent-view.tsx

@@ -1,6 +1,5 @@
 import { useState, useCallback, useRef, useEffect } from 'react';
 import { useAppStore } from '@/store/app-store';
-import type { PhaseModelEntry } from '@automaker/types';
 import { useElectronAgent } from '@/hooks/use-electron-agent';
 import { SessionManager } from '@/components/session-manager';
 
@@ -46,8 +45,6 @@ export function AgentView() {
     return () => window.removeEventListener('resize', updateVisibility);
   }, []);
 
-  const [modelSelection, setModelSelection] = useState<PhaseModelEntry>({ model: 'claude-sonnet' });
-
   // Input ref for auto-focus
   const inputRef = useRef<HTMLTextAreaElement>(null);
 
@@ -57,10 +54,12 @@ export function AgentView() {
   const createSessionInFlightRef = useRef(false);
 
   // Session management hook - scoped to current worktree
-  const { currentSessionId, handleSelectSession } = useAgentSession({
-    projectPath: currentProject?.path,
-    workingDirectory: effectiveWorkingDirectory,
-  });
+  // Also handles model selection persistence per session
+  const { currentSessionId, handleSelectSession, modelSelection, setModelSelection } =
+    useAgentSession({
+      projectPath: currentProject?.path,
+      workingDirectory: effectiveWorkingDirectory,
+    });
 
   // Use the Electron agent hook (only if we have a session)
   const {

apps/ui/src/components/views/agent-view/hooks/use-agent-session.ts

@@ -1,9 +1,14 @@
 import { useState, useCallback, useEffect, useRef } from 'react';
 import { createLogger } from '@automaker/utils/logger';
+import type { PhaseModelEntry } from '@automaker/types';
 import { useAppStore } from '@/store/app-store';
+import { useShallow } from 'zustand/react/shallow';
 
 const logger = createLogger('AgentSession');
 
+// Default model selection when none is persisted
+const DEFAULT_MODEL_SELECTION: PhaseModelEntry = { model: 'claude-sonnet' };
+
 interface UseAgentSessionOptions {
   projectPath: string | undefined;
   workingDirectory?: string; // Current worktree path for per-worktree session persistence
@@ -12,14 +17,31 @@ interface UseAgentSessionOptions {
 interface UseAgentSessionResult {
   currentSessionId: string | null;
   handleSelectSession: (sessionId: string | null) => void;
+  // Model selection persistence
+  modelSelection: PhaseModelEntry;
+  setModelSelection: (model: PhaseModelEntry) => void;
 }
 
 export function useAgentSession({
   projectPath,
   workingDirectory,
 }: UseAgentSessionOptions): UseAgentSessionResult {
-  const { setLastSelectedSession, getLastSelectedSession } = useAppStore();
+  const {
+    setLastSelectedSession,
+    getLastSelectedSession,
+    setAgentModelForSession,
+    getAgentModelForSession,
+  } = useAppStore(
+    useShallow((state) => ({
+      setLastSelectedSession: state.setLastSelectedSession,
+      getLastSelectedSession: state.getLastSelectedSession,
+      setAgentModelForSession: state.setAgentModelForSession,
+      getAgentModelForSession: state.getAgentModelForSession,
+    }))
+  );
   const [currentSessionId, setCurrentSessionId] = useState<string | null>(null);
+  const [modelSelection, setModelSelectionState] =
+    useState<PhaseModelEntry>(DEFAULT_MODEL_SELECTION);
 
   // Track if initial session has been loaded
   const initialSessionLoadedRef = useRef(false);
@@ -27,6 +49,22 @@ export function useAgentSession({
   // Use workingDirectory as the persistence key so sessions are scoped per worktree
   const persistenceKey = workingDirectory || projectPath;
 
+  /**
+   * Fetch persisted model for sessionId and update local state, or fall back to default.
+   */
+  const restoreModelForSession = useCallback(
+    (sessionId: string) => {
+      const persistedModel = getAgentModelForSession(sessionId);
+      if (persistedModel) {
+        logger.debug('Restoring model selection for session:', sessionId, persistedModel);
+        setModelSelectionState(persistedModel);
+      } else {
+        setModelSelectionState(DEFAULT_MODEL_SELECTION);
+      }
+    },
+    [getAgentModelForSession]
+  );
+
   // Handle session selection with persistence
   const handleSelectSession = useCallback(
     (sessionId: string | null) => {
@@ -35,16 +73,52 @@ export function useAgentSession({
       if (persistenceKey) {
         setLastSelectedSession(persistenceKey, sessionId);
       }
+      // Restore model selection for this session if available
+      if (sessionId) {
+        restoreModelForSession(sessionId);
+      }
     },
-    [persistenceKey, setLastSelectedSession]
+    [persistenceKey, setLastSelectedSession, restoreModelForSession]
   );
 
+  // Wrapper for setModelSelection that also persists
+  const setModelSelection = useCallback(
+    (model: PhaseModelEntry) => {
+      setModelSelectionState(model);
+      // Persist model selection for current session.
+      // If currentSessionId is null (no active session), we only update local state
+      // and skip persistence — this is intentional because the model picker should be
+      // disabled (or hidden) in the UI whenever there is no active session, so this
+      // path is only reached if the UI allows selection before a session is established.
+      if (currentSessionId) {
+        setAgentModelForSession(currentSessionId, model);
+      }
+    },
+    [currentSessionId, setAgentModelForSession]
+  );
+
+  // Track the previous persistence key to detect actual changes
+  const prevPersistenceKeyRef = useRef(persistenceKey);
+
   // Restore last selected session when switching to Agent view or when worktree changes
   useEffect(() => {
-    if (!persistenceKey) {
-      // No project, reset
-      setCurrentSessionId(null);
+    // Detect if persistenceKey actually changed (worktree/project switch)
+    const persistenceKeyChanged = prevPersistenceKeyRef.current !== persistenceKey;
+
+    if (persistenceKeyChanged) {
+      // Reset state when switching worktree/project
+      prevPersistenceKeyRef.current = persistenceKey;
       initialSessionLoadedRef.current = false;
+      setCurrentSessionId(null);
+      setModelSelectionState(DEFAULT_MODEL_SELECTION);
+
+      if (!persistenceKey) {
+        // No project, nothing to restore
+        return;
+      }
+    }
+
+    if (!persistenceKey) {
       return;
     }
 
@@ -54,19 +128,17 @@ export function useAgentSession({
 
     const lastSessionId = getLastSelectedSession(persistenceKey);
     if (lastSessionId) {
-      logger.info('Restoring last selected session:', lastSessionId);
+      logger.debug('Restoring last selected session:', lastSessionId);
       setCurrentSessionId(lastSessionId);
+      // Also restore model selection for this session
+      restoreModelForSession(lastSessionId);
     }
-  }, [persistenceKey, getLastSelectedSession]);
-
-  // Reset when worktree/project changes - clear current session and allow restore
-  useEffect(() => {
-    initialSessionLoadedRef.current = false;
-    setCurrentSessionId(null);
-  }, [persistenceKey]);
+  }, [persistenceKey, getLastSelectedSession, restoreModelForSession]);
 
   return {
     currentSessionId,
     handleSelectSession,
+    modelSelection,
+    setModelSelection,
   };
 }

apps/ui/src/components/views/board-view.tsx

@@ -116,7 +116,6 @@ export function BoardView() {
     setPendingPlanApproval,
     updateFeature,
     batchUpdateFeatures,
-    getCurrentWorktree,
     setCurrentWorktree,
     getWorktrees,
     setWorktrees,
@@ -135,7 +134,6 @@ export function BoardView() {
       setPendingPlanApproval: state.setPendingPlanApproval,
       updateFeature: state.updateFeature,
       batchUpdateFeatures: state.batchUpdateFeatures,
-      getCurrentWorktree: state.getCurrentWorktree,
       setCurrentWorktree: state.setCurrentWorktree,
       getWorktrees: state.getWorktrees,
       setWorktrees: state.setWorktrees,
@@ -444,9 +442,17 @@ export function BoardView() {
     [batchResetBranchFeatures]
   );
 
-  // Get current worktree info (path) for filtering features
-  // This needs to be before useBoardActions so we can pass currentWorktreeBranch
-  const currentWorktreeInfo = currentProject ? getCurrentWorktree(currentProject.path) : null;
+  const currentProjectPath = currentProject?.path;
+
+  // Get current worktree info (path/branch) for filtering features.
+  // Subscribe to the selected project's current worktree value directly so worktree
+  // switches trigger an immediate re-render and instant kanban/list re-filtering.
+  const currentWorktreeInfo = useAppStore(
+    useCallback(
+      (s) => (currentProjectPath ? (s.currentWorktreeByProject[currentProjectPath] ?? null) : null),
+      [currentProjectPath]
+    )
+  );
   const currentWorktreePath = currentWorktreeInfo?.path ?? null;
 
   // Select worktrees for the current project directly from the store.
@@ -455,7 +461,6 @@ export function BoardView() {
   // object, causing unnecessary re-renders that cascaded into selectedWorktree →
   // useAutoMode → refreshStatus → setAutoModeRunning → store update → re-render loop
   // that could trigger React error #185 on initial project open).
-  const currentProjectPath = currentProject?.path;
   const worktrees = useAppStore(
     useCallback(
       (s) =>

apps/ui/src/components/views/board-view/dialogs/commit-worktree-dialog.tsx

@@ -1,4 +1,4 @@
-import { useState, useEffect, useMemo, useCallback } from 'react';
+import { useState, useEffect, useMemo, useCallback, useRef } from 'react';
 import {
   Dialog,
   DialogContent,
@@ -30,13 +30,17 @@ import {
   ChevronDown,
   ChevronRight,
   Upload,
+  RefreshCw,
 } from 'lucide-react';
 import { Spinner } from '@/components/ui/spinner';
 import { getElectronAPI } from '@/lib/electron';
+import { getHttpApiClient } from '@/lib/http-api-client';
 import { toast } from 'sonner';
 import { useAppStore } from '@/store/app-store';
+import { resolveModelString } from '@automaker/model-resolver';
 import { cn } from '@/lib/utils';
 import { TruncatedFilePath } from '@/components/ui/truncated-file-path';
+import { ModelOverrideTrigger, useModelOverride } from '@/components/shared';
 import type { FileStatus, MergeStateInfo } from '@/types/electron';
 import { parseDiff, type ParsedFileDiff } from '@/lib/diff-utils';
 
@@ -206,6 +210,11 @@ export function CommitWorktreeDialog({
   const [error, setError] = useState<string | null>(null);
   const enableAiCommitMessages = useAppStore((state) => state.enableAiCommitMessages);
 
+  // Commit message model override
+  const commitModelOverride = useModelOverride({ phase: 'commitMessageModel' });
+  const { effectiveModel: commitEffectiveModel, effectiveModelEntry: commitEffectiveModelEntry } =
+    commitModelOverride;
+
   // File selection state
   const [files, setFiles] = useState<FileStatus[]>([]);
   const [diffContent, setDiffContent] = useState('');
@@ -532,6 +541,46 @@ export function CommitWorktreeDialog({
     }
   };
 
+  // Generate AI commit message
+  const generateCommitMessage = useCallback(async () => {
+    if (!worktree) return;
+
+    setIsGenerating(true);
+    try {
+      const resolvedCommitModel = resolveModelString(commitEffectiveModel);
+      const api = getHttpApiClient();
+      const result = await api.worktree.generateCommitMessage(
+        worktree.path,
+        resolvedCommitModel,
+        commitEffectiveModelEntry?.thinkingLevel,
+        commitEffectiveModelEntry?.providerId
+      );
+
+      if (result.success && result.message) {
+        setMessage(result.message);
+      } else {
+        console.warn('Failed to generate commit message:', result.error);
+        toast.error('Failed to generate commit message', {
+          description: result.error || 'Unknown error',
+        });
+      }
+    } catch (err) {
+      console.warn('Error generating commit message:', err);
+      toast.error('Failed to generate commit message', {
+        description: err instanceof Error ? err.message : 'Unknown error',
+      });
+    } finally {
+      setIsGenerating(false);
+    }
+  }, [worktree, commitEffectiveModel, commitEffectiveModelEntry]);
+
+  // Keep a stable ref to generateCommitMessage so the open-dialog effect
+  // doesn't re-fire (and erase user edits) when the model override changes.
+  const generateCommitMessageRef = useRef(generateCommitMessage);
+  useEffect(() => {
+    generateCommitMessageRef.current = generateCommitMessage;
+  });
+
   // Generate AI commit message when dialog opens (if enabled)
   useEffect(() => {
     if (open && worktree) {
@@ -543,45 +592,7 @@ export function CommitWorktreeDialog({
         return;
       }
 
-      setIsGenerating(true);
-      let cancelled = false;
-
-      const generateMessage = async () => {
-        try {
-          const api = getElectronAPI();
-          if (!api?.worktree?.generateCommitMessage) {
-            if (!cancelled) {
-              setIsGenerating(false);
-            }
-            return;
-          }
-
-          const result = await api.worktree.generateCommitMessage(worktree.path);
-
-          if (cancelled) return;
-
-          if (result.success && result.message) {
-            setMessage(result.message);
-          } else {
-            console.warn('Failed to generate commit message:', result.error);
-            setMessage('');
-          }
-        } catch (err) {
-          if (cancelled) return;
-          console.warn('Error generating commit message:', err);
-          setMessage('');
-        } finally {
-          if (!cancelled) {
-            setIsGenerating(false);
-          }
-        }
-      };
-
-      generateMessage();
-
-      return () => {
-        cancelled = true;
-      };
+      generateCommitMessageRef.current();
     }
   }, [open, worktree, enableAiCommitMessages]);
 
@@ -589,12 +600,12 @@ export function CommitWorktreeDialog({
 
   const allSelected = selectedFiles.size === files.length && files.length > 0;
 
-  // Prevent the dialog from being dismissed while a push is in progress.
+  // Prevent the dialog from being dismissed while a push or generation is in progress.
   // Overlay clicks and Escape key both route through onOpenChange(false); we
-  // intercept those here so the UI stays open until the push completes.
+  // intercept those here so the UI stays open until the operation completes.
   const handleOpenChange = (nextOpen: boolean) => {
-    if (!nextOpen && isPushing) {
-      // Ignore close requests during an active push.
+    if (!nextOpen && (isLoading || isPushing || isGenerating)) {
+      // Ignore close requests during an active commit, push, or generation.
       return;
     }
     onOpenChange(nextOpen);
@@ -813,15 +824,46 @@ export function CommitWorktreeDialog({
 
           {/* Commit Message */}
           <div className="grid gap-1.5">
-            <Label htmlFor="commit-message" className="flex items-center gap-2">
-              Commit Message
-              {isGenerating && (
-                <span className="flex items-center gap-1 text-xs text-muted-foreground">
-                  <Sparkles className="w-3 h-3 animate-pulse" />
-                  Generating...
-                </span>
-              )}
-            </Label>
+            <div className="flex items-center justify-between">
+              <Label htmlFor="commit-message" className="flex items-center gap-2">
+                Commit Message
+                {isGenerating && (
+                  <span className="flex items-center gap-1 text-xs text-muted-foreground">
+                    <Sparkles className="w-3 h-3 animate-pulse" />
+                    Generating...
+                  </span>
+                )}
+              </Label>
+              <div className="flex items-center gap-1">
+                {enableAiCommitMessages && (
+                  <>
+                    <Button
+                      variant="ghost"
+                      size="sm"
+                      onClick={generateCommitMessage}
+                      disabled={isGenerating || isLoading}
+                      className="h-6 px-2 text-xs"
+                      title="Regenerate commit message"
+                    >
+                      {isGenerating ? (
+                        <Spinner size="xs" className="mr-1" />
+                      ) : (
+                        <RefreshCw className="w-3 h-3 mr-1" />
+                      )}
+                      Regenerate
+                    </Button>
+                    <ModelOverrideTrigger
+                      currentModelEntry={commitModelOverride.effectiveModelEntry}
+                      onModelChange={commitModelOverride.setOverride}
+                      phase="commitMessageModel"
+                      isOverridden={commitModelOverride.isOverridden}
+                      size="sm"
+                      variant="icon"
+                    />
+                  </>
+                )}
+              </div>
+            </div>
             <Textarea
               id="commit-message"
               placeholder={

apps/ui/src/components/views/board-view/dialogs/create-pr-dialog.tsx

@@ -26,6 +26,7 @@ import { getElectronAPI } from '@/lib/electron';
 import { getHttpApiClient } from '@/lib/http-api-client';
 import { toast } from 'sonner';
 import { useWorktreeBranches } from '@/hooks/queries';
+import { ModelOverrideTrigger, useModelOverride } from '@/components/shared';
 
 interface RemoteInfo {
   name: string;
@@ -92,6 +93,9 @@ export function CreatePRDialog({
   // Generate description state
   const [isGeneratingDescription, setIsGeneratingDescription] = useState(false);
 
+  // PR description model override
+  const prDescriptionModelOverride = useModelOverride({ phase: 'prDescriptionModel' });
+
   // Use React Query for branch fetching - only enabled when dialog is open
   const { data: branchesData, isLoading: isLoadingBranches } = useWorktreeBranches(
     open ? worktree?.path : undefined,
@@ -306,7 +310,13 @@ export function CreatePRDialog({
         resolvedRef !== baseBranch && resolvedRef.includes('/')
           ? resolvedRef.substring(resolvedRef.indexOf('/') + 1)
           : resolvedRef;
-      const result = await api.worktree.generatePRDescription(worktree.path, branchNameForApi);
+      const result = await api.worktree.generatePRDescription(
+        worktree.path,
+        branchNameForApi,
+        prDescriptionModelOverride.effectiveModel,
+        prDescriptionModelOverride.effectiveModelEntry.thinkingLevel,
+        prDescriptionModelOverride.effectiveModelEntry.providerId
+      );
 
       if (result.success) {
         if (result.title) {
@@ -587,30 +597,40 @@ export function CreatePRDialog({
               <div className="grid gap-2">
                 <div className="flex items-center justify-between">
                   <Label htmlFor="pr-title">PR Title</Label>
-                  <Button
-                    variant="ghost"
-                    size="sm"
-                    onClick={handleGenerateDescription}
-                    disabled={isGeneratingDescription || isLoading}
-                    className="h-6 px-2 text-xs"
-                    title={
-                      worktree.hasChanges
-                        ? 'Generate title and description from commits and uncommitted changes'
-                        : 'Generate title and description from commits'
-                    }
-                  >
-                    {isGeneratingDescription ? (
-                      <>
-                        <Spinner size="xs" className="mr-1" />
-                        Generating...
-                      </>
-                    ) : (
-                      <>
-                        <Sparkles className="w-3 h-3 mr-1" />
-                        Generate with AI
-                      </>
-                    )}
-                  </Button>
+                  <div className="flex items-center gap-1">
+                    <Button
+                      variant="ghost"
+                      size="sm"
+                      onClick={handleGenerateDescription}
+                      disabled={isGeneratingDescription || isLoading}
+                      className="h-6 px-2 text-xs"
+                      title={
+                        worktree.hasChanges
+                          ? 'Generate title and description from commits and uncommitted changes'
+                          : 'Generate title and description from commits'
+                      }
+                    >
+                      {isGeneratingDescription ? (
+                        <>
+                          <Spinner size="xs" className="mr-1" />
+                          Generating...
+                        </>
+                      ) : (
+                        <>
+                          <Sparkles className="w-3 h-3 mr-1" />
+                          Generate with AI
+                        </>
+                      )}
+                    </Button>
+                    <ModelOverrideTrigger
+                      currentModelEntry={prDescriptionModelOverride.effectiveModelEntry}
+                      onModelChange={prDescriptionModelOverride.setOverride}
+                      phase="prDescriptionModel"
+                      isOverridden={prDescriptionModelOverride.isOverridden}
+                      size="sm"
+                      variant="icon"
+                    />
+                  </div>
                 </div>
                 <Input
                   id="pr-title"

apps/ui/src/hooks/use-settings-sync.ts

@@ -109,6 +109,7 @@ const SETTINGS_FIELDS_TO_SYNC = [
   'projectHistory',
   'projectHistoryIndex',
   'lastSelectedSessionByProject',
+  'agentModelBySession',
   'currentWorktreeByProject',
   // Codex CLI Settings
   'codexAutoLoadAgents',
@@ -173,6 +174,17 @@ function getSettingsFieldValue(
     }
     return persistedSettings;
   }
+  if (field === 'agentModelBySession') {
+    // Cap to the 50 most-recently-inserted session entries to prevent unbounded growth.
+    // agentModelBySession grows by one entry per agent session — without pruning this
+    // will bloat settings.json, every debounced sync payload, and the localStorage cache.
+    const map = appState.agentModelBySession as Record<string, unknown>;
+    const MAX_ENTRIES = 50;
+    const entries = Object.entries(map);
+    if (entries.length <= MAX_ENTRIES) return map;
+    // Keep the last MAX_ENTRIES entries (insertion-order approximation for recency)
+    return Object.fromEntries(entries.slice(-MAX_ENTRIES));
+  }
   return appState[field as keyof typeof appState];
 }
 
@@ -806,6 +818,13 @@ export async function refreshSettingsFromServer(): Promise<boolean> {
       projectHistory: serverSettings.projectHistory,
       projectHistoryIndex: serverSettings.projectHistoryIndex,
       lastSelectedSessionByProject: serverSettings.lastSelectedSessionByProject,
+      agentModelBySession: serverSettings.agentModelBySession
+        ? Object.fromEntries(
+            Object.entries(serverSettings.agentModelBySession as Record<string, unknown>).map(
+              ([sessionId, entry]) => [sessionId, migratePhaseModelEntry(entry)]
+            )
+          )
+        : currentAppState.agentModelBySession,
       // Sanitize: only restore entries with path === null (main branch).
       // Non-null paths may reference deleted worktrees, causing crash loops.
       currentWorktreeByProject: sanitizeWorktreeByProject(

apps/ui/src/lib/http-api-client.ts

@@ -2204,10 +2204,32 @@ export class HttpApiClient implements ElectronAPI {
       }),
     commit: (worktreePath: string, message: string, files?: string[]) =>
       this.post('/api/worktree/commit', { worktreePath, message, files }),
-    generateCommitMessage: (worktreePath: string) =>
-      this.post('/api/worktree/generate-commit-message', { worktreePath }),
-    generatePRDescription: (worktreePath: string, baseBranch?: string) =>
-      this.post('/api/worktree/generate-pr-description', { worktreePath, baseBranch }),
+    generateCommitMessage: (
+      worktreePath: string,
+      model?: string,
+      thinkingLevel?: string,
+      providerId?: string
+    ) =>
+      this.post('/api/worktree/generate-commit-message', {
+        worktreePath,
+        model,
+        thinkingLevel,
+        providerId,
+      }),
+    generatePRDescription: (
+      worktreePath: string,
+      baseBranch?: string,
+      model?: string,
+      thinkingLevel?: string,
+      providerId?: string
+    ) =>
+      this.post('/api/worktree/generate-pr-description', {
+        worktreePath,
+        baseBranch,
+        model,
+        thinkingLevel,
+        providerId,
+      }),
     push: (worktreePath: string, force?: boolean, remote?: string, autoResolve?: boolean) =>
       this.post('/api/worktree/push', { worktreePath, force, remote, autoResolve }),
     sync: (worktreePath: string, remote?: string) =>

apps/ui/src/lib/settings-utils.ts

@@ -3,10 +3,14 @@
  */
 
 /**
- * Drop currentWorktreeByProject entries with non-null paths.
- * Non-null paths reference worktree directories that may have been deleted,
- * and restoring them causes crash loops (board renders invalid worktree
- * -> error boundary reloads -> restores same stale path).
+ * Validate and sanitize currentWorktreeByProject entries.
+ *
+ * Keeps all valid entries (both main branch and feature worktrees).
+ * The validation against actual worktrees happens in use-worktrees.ts
+ * which resets to main branch if the selected worktree no longer exists.
+ *
+ * Only drops entries with invalid structure (not an object, missing/invalid
+ * path or branch).
  */
 export function sanitizeWorktreeByProject(
   raw: Record<string, { path: string | null; branch: string }> | undefined
@@ -14,11 +18,13 @@ export function sanitizeWorktreeByProject(
   if (!raw) return {};
   const sanitized: Record<string, { path: string | null; branch: string }> = {};
   for (const [projectPath, worktree] of Object.entries(raw)) {
+    // Only validate structure - keep both null (main) and non-null (worktree) paths
+    // Runtime validation in use-worktrees.ts handles deleted worktrees
     if (
       typeof worktree === 'object' &&
       worktree !== null &&
-      'path' in worktree &&
-      worktree.path === null
+      typeof worktree.branch === 'string' &&
+      (worktree.path === null || typeof worktree.path === 'string')
     ) {
       sanitized[projectPath] = worktree;
     }

apps/ui/src/store/app-store.ts

@@ -275,6 +275,7 @@ const initialState: AppState = {
   collapsedNavSections: cachedUI.collapsedNavSections,
   mobileSidebarHidden: false,
   lastSelectedSessionByProject: {},
+  agentModelBySession: {},
   theme: getStoredTheme() || 'dark',
   fontFamilySans: getStoredFontSans(),
   fontFamilyMono: getStoredFontMono(),
@@ -962,11 +963,15 @@ export const useAppStore = create<AppState & AppActions>()((set, get) => ({
       ),
     })),
   deleteChatSession: (sessionId) =>
-    set((state) => ({
-      chatSessions: state.chatSessions.filter((s) => s.id !== sessionId),
-      currentChatSession:
-        state.currentChatSession?.id === sessionId ? null : state.currentChatSession,
-    })),
+    set((state) => {
+      const { [sessionId]: _removed, ...remainingAgentModels } = state.agentModelBySession;
+      return {
+        chatSessions: state.chatSessions.filter((s) => s.id !== sessionId),
+        currentChatSession:
+          state.currentChatSession?.id === sessionId ? null : state.currentChatSession,
+        agentModelBySession: remainingAgentModels,
+      };
+    }),
   setChatHistoryOpen: (open) => set({ chatHistoryOpen: open }),
   toggleChatHistory: () => set((state) => ({ chatHistoryOpen: !state.chatHistoryOpen })),
 
@@ -1598,6 +1603,16 @@ export const useAppStore = create<AppState & AppActions>()((set, get) => ({
     })),
   getLastSelectedSession: (projectPath) => get().lastSelectedSessionByProject[projectPath] ?? null,
 
+  // Agent model selection actions
+  setAgentModelForSession: (sessionId, model) =>
+    set((state) => ({
+      agentModelBySession: {
+        ...state.agentModelBySession,
+        [sessionId]: model,
+      },
+    })),
+  getAgentModelForSession: (sessionId) => get().agentModelBySession[sessionId] ?? null,
+
   // Board Background actions
   setBoardBackground: (projectPath, imagePath) =>
     set((state) => ({

apps/ui/src/store/types/state-types.ts

@@ -83,6 +83,8 @@ export interface AppState {
 
   // Agent Session state (per-project, keyed by project path)
   lastSelectedSessionByProject: Record<string, string>; // projectPath -> sessionId
+  // Agent model selection (per-session, keyed by sessionId)
+  agentModelBySession: Record<string, PhaseModelEntry>; // sessionId -> model selection
 
   // Theme
   theme: ThemeMode;
@@ -669,6 +671,9 @@ export interface AppActions {
   // Agent Session actions
   setLastSelectedSession: (projectPath: string, sessionId: string | null) => void;
   getLastSelectedSession: (projectPath: string) => string | null;
+  // Agent model selection actions
+  setAgentModelForSession: (sessionId: string, model: PhaseModelEntry) => void;
+  getAgentModelForSession: (sessionId: string) => PhaseModelEntry | null;
 
   // Board Background actions
   setBoardBackground: (projectPath: string, imagePath: string | null) => void;

apps/ui/src/store/ui-cache-store.ts

@@ -81,6 +81,38 @@ export const useUICacheStore = create<UICacheState & UICacheActions>()(
   )
 );
 
+/**
+ * Check whether an unknown value is a valid cached worktree entry.
+ * Accepts objects with a non-empty string branch and a path that is null or a string.
+ */
+function isValidCachedWorktreeEntry(
+  worktree: unknown
+): worktree is { path: string | null; branch: string } {
+  return (
+    typeof worktree === 'object' &&
+    worktree !== null &&
+    typeof (worktree as Record<string, unknown>).branch === 'string' &&
+    ((worktree as Record<string, unknown>).branch as string).trim().length > 0 &&
+    ((worktree as Record<string, unknown>).path === null ||
+      typeof (worktree as Record<string, unknown>).path === 'string')
+  );
+}
+
+/**
+ * Filter a raw worktree map, discarding entries that fail structural validation.
+ */
+function sanitizeCachedWorktreeByProject(
+  raw: Record<string, unknown>
+): Record<string, { path: string | null; branch: string }> {
+  const sanitized: Record<string, { path: string | null; branch: string }> = {};
+  for (const [key, worktree] of Object.entries(raw)) {
+    if (isValidCachedWorktreeEntry(worktree)) {
+      sanitized[key] = worktree;
+    }
+  }
+  return sanitized;
+}
+
 /**
  * Sync critical UI state from the main app store to the UI cache.
  * Call this whenever the app store changes to keep the cache up to date.
@@ -114,24 +146,14 @@ export function syncUICache(appState: {
     update.cachedCollapsedNavSections = appState.collapsedNavSections;
   }
   if ('currentWorktreeByProject' in appState && appState.currentWorktreeByProject) {
-    // Sanitize on write: only persist entries where path is null (main branch).
-    // Non-null paths point to worktree directories on disk that may be deleted
-    // while the app is not running. Persisting stale paths can cause crash loops
-    // on restore (the board renders with an invalid selection, the error boundary
-    // reloads, which restores the same bad cache). This mirrors the sanitization
-    // in restoreFromUICache() for defense-in-depth.
-    const sanitized: Record<string, { path: string | null; branch: string }> = {};
-    for (const [projectPath, worktree] of Object.entries(appState.currentWorktreeByProject)) {
-      if (
-        typeof worktree === 'object' &&
-        worktree !== null &&
-        'path' in worktree &&
-        worktree.path === null
-      ) {
-        sanitized[projectPath] = worktree;
-      }
-    }
-    update.cachedCurrentWorktreeByProject = sanitized;
+    // Persist all valid worktree selections (both main branch and feature worktrees).
+    // Validation against actual worktrees happens at restore time in:
+    // 1. restoreFromUICache() - early restore with validation
+    // 2. use-worktrees.ts - runtime validation that resets to main if deleted
+    // This allows users to have their feature worktree selection persist across refreshes.
+    update.cachedCurrentWorktreeByProject = sanitizeCachedWorktreeByProject(
+      appState.currentWorktreeByProject as Record<string, unknown>
+    );
   }
 
   if (Object.keys(update).length > 0) {
@@ -178,33 +200,18 @@ export function restoreFromUICache(
   // Restore last selected worktree per project so the board doesn't
   // reset to main branch after PWA memory eviction or tab discard.
   //
-  // IMPORTANT: Only restore entries where path is null (main branch selection).
-  // Non-null paths point to worktree directories on disk that may have been
-  // deleted while the PWA was evicted. Restoring a stale worktree path causes
-  // the board to render with an invalid selection, and if the server can't
-  // validate it fast enough, the app enters an unrecoverable crash loop
-  // (the error boundary reloads, which restores the same bad cache).
-  // Main branch (path=null) is always valid and safe to restore.
+  // Restore all valid worktree selections (both main branch and feature worktrees).
+  // The validation effect in use-worktrees.ts will handle resetting to main branch
+  // if the cached worktree no longer exists when worktree data loads.
   if (
     cache.cachedCurrentWorktreeByProject &&
     Object.keys(cache.cachedCurrentWorktreeByProject).length > 0
   ) {
-    const sanitized: Record<string, { path: string | null; branch: string }> = {};
-    for (const [projectPath, worktree] of Object.entries(cache.cachedCurrentWorktreeByProject)) {
-      if (
-        typeof worktree === 'object' &&
-        worktree !== null &&
-        'path' in worktree &&
-        worktree.path === null
-      ) {
-        // Main branch selection — always safe to restore
-        sanitized[projectPath] = worktree;
-      }
-      // Non-null paths are dropped; the app will re-discover actual worktrees
-      // from the server and the validation effect in use-worktrees will handle
-      // resetting to main if the cached worktree no longer exists.
-      // Null/malformed entries are also dropped to prevent crashes.
-    }
+    // Validate structure only - keep both null (main) and non-null (worktree) paths
+    // Runtime validation in use-worktrees.ts handles deleted worktrees gracefully
+    const sanitized = sanitizeCachedWorktreeByProject(
+      cache.cachedCurrentWorktreeByProject as Record<string, unknown>
+    );
     if (Object.keys(sanitized).length > 0) {
       stateUpdate.currentWorktreeByProject = sanitized;
     }

apps/ui/src/types/electron.d.ts

@@ -959,7 +959,12 @@ export interface WorktreeAPI {
   }>;
 
   // Generate an AI commit message from git diff
-  generateCommitMessage: (worktreePath: string) => Promise<{
+  generateCommitMessage: (
+    worktreePath: string,
+    model?: string,
+    thinkingLevel?: string,
+    providerId?: string
+  ) => Promise<{
     success: boolean;
     message?: string;
     error?: string;
@@ -968,7 +973,10 @@ export interface WorktreeAPI {
   // Generate an AI PR title and description from branch diff
   generatePRDescription: (
     worktreePath: string,
-    baseBranch?: string
+    baseBranch?: string,
+    model?: string,
+    thinkingLevel?: string,
+    providerId?: string
   ) => Promise<{
     success: boolean;
     title?: string;