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references/accessibility.md

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+# Accessibility (a11y) Best Practices
+
+Complete guide for building accessible forms.
+
+---
+
+## WCAG Compliance
+
+### Required Elements
+
+1. **Labels** - Every input must have a label
+2. **Error Messages** - Must be accessible to screen readers
+3. **Focus Management** - Errors should be announced
+4. **Keyboard Navigation** - Full keyboard support
+
+---
+
+## ARIA Attributes
+
+### Essential ARIA
+
+```typescript
+<input
+  id="email"
+  type="email"
+  {...register('email')}
+  aria-invalid={errors.email ? 'true' : 'false'}
+  aria-describedby={errors.email ? 'email-error' : 'email-hint'}
+  aria-required="true"
+/>
+
+<span id="email-hint">We'll never share your email</span>
+
+{errors.email && (
+  <span id="email-error" role="alert">
+    {errors.email.message}
+  </span>
+)}
+```
+
+### Live Regions for Error Announcements
+
+```typescript
+{Object.keys(errors).length > 0 && (
+  <div role="alert" aria-live="assertive" aria-atomic="true">
+    Form has {Object.keys(errors).length} errors. Please review.
+  </div>
+)}
+```
+
+---
+
+## Focus Management
+
+### Focus First Error
+
+```typescript
+import { useEffect, useRef } from 'react'
+
+const firstErrorRef = useRef<HTMLInputElement>(null)
+
+useEffect(() => {
+  if (Object.keys(errors).length > 0) {
+    firstErrorRef.current?.focus()
+  }
+}, [errors])
+
+// In JSX
+<input
+  ref={Object.keys(errors)[0] === 'email' ? firstErrorRef : undefined}
+  {...register('email')}
+/>
+```
+
+### Using setFocus
+
+```typescript
+const onSubmit = async (data) => {
+  try {
+    await submitData(data)
+  } catch (error) {
+    setFocus('email') // Focus field programmatically
+  }
+}
+```
+
+---
+
+## Label Association
+
+### Explicit Labels
+
+```typescript
+<label htmlFor="email">Email Address</label>
+<input id="email" {...register('email')} />
+```
+
+### aria-label (When Visual Label Not Possible)
+
+```typescript
+<input
+  {...register('search')}
+  aria-label="Search products"
+  placeholder="Search..."
+/>
+```
+
+### aria-labelledby (Multiple Labels)
+
+```typescript
+<h3 id="billing-heading">Billing Address</h3>
+<input
+  {...register('billingStreet')}
+  aria-labelledby="billing-heading billing-street-label"
+/>
+<span id="billing-street-label">Street</span>
+```
+
+---
+
+## Required Fields
+
+### Visual Indicator
+
+```typescript
+<label htmlFor="email">
+  Email <span aria-label="required">*</span>
+</label>
+<input
+  id="email"
+  {...register('email')}
+  aria-required="true"
+  required
+/>
+```
+
+### Legend for Required Fields
+
+```typescript
+<p className="required-legend">
+  <span aria-label="required">*</span> Required field
+</p>
+```
+
+---
+
+## Error Messaging
+
+### Accessible Error Pattern
+
+```typescript
+<div>
+  <label htmlFor="password">Password</label>
+  <input
+    id="password"
+    type="password"
+    {...register('password')}
+    aria-invalid={errors.password ? 'true' : 'false'}
+    aria-describedby={errors.password ? 'password-error' : 'password-hint'}
+  />
+
+  <span id="password-hint" className="hint">
+    Must be at least 8 characters
+  </span>
+
+  {errors.password && (
+    <span id="password-error" role="alert" className="error">
+      {errors.password.message}
+    </span>
+  )}
+</div>
+```
+
+---
+
+## Fieldsets and Legends
+
+### Grouping Related Fields
+
+```typescript
+<fieldset>
+  <legend>Contact Information</legend>
+
+  <div>
+    <label htmlFor="firstName">First Name</label>
+    <input id="firstName" {...register('firstName')} />
+  </div>
+
+  <div>
+    <label htmlFor="lastName">Last Name</label>
+    <input id="lastName" {...register('lastName')} />
+  </div>
+</fieldset>
+```
+
+### Radio Groups
+
+```typescript
+<fieldset>
+  <legend>Choose your plan</legend>
+
+  <div>
+    <input
+      id="plan-basic"
+      type="radio"
+      value="basic"
+      {...register('plan')}
+    />
+    <label htmlFor="plan-basic">Basic</label>
+  </div>
+
+  <div>
+    <input
+      id="plan-pro"
+      type="radio"
+      value="pro"
+      {...register('plan')}
+    />
+    <label htmlFor="plan-pro">Pro</label>
+  </div>
+</fieldset>
+```
+
+---
+
+## Keyboard Navigation
+
+### Tab Order
+
+```typescript
+// Ensure logical tab order with tabindex (use sparingly)
+<input {...register('email')} tabIndex={1} />
+<input {...register('password')} tabIndex={2} />
+<button type="submit" tabIndex={3}>Submit</button>
+```
+
+### Skip Links
+
+```typescript
+<a href="#main-form" className="skip-link">
+  Skip to form
+</a>
+
+<form id="main-form">
+  {/* ... */}
+</form>
+```
+
+---
+
+## Button Accessibility
+
+### Submit Button States
+
+```typescript
+<button
+  type="submit"
+  disabled={isSubmitting}
+  aria-busy={isSubmitting ? 'true' : 'false'}
+  aria-live="polite"
+>
+  {isSubmitting ? 'Submitting...' : 'Submit Form'}
+</button>
+```
+
+### Icon Buttons
+
+```typescript
+<button type="button" aria-label="Remove item" onClick={remove}>
+  <TrashIcon aria-hidden="true" />
+</button>
+```
+
+---
+
+## Screen Reader Announcements
+
+### Status Messages
+
+```typescript
+{isSubmitSuccessful && (
+  <div role="status" aria-live="polite">
+    Form submitted successfully!
+  </div>
+)}
+```
+
+### Loading States
+
+```typescript
+{isSubmitting && (
+  <div role="status" aria-live="polite">
+    Submitting form, please wait...
+  </div>
+)}
+```
+
+---
+
+## Color Contrast
+
+### WCAG AA Standards
+
+- Normal text: 4.5:1 minimum
+- Large text: 3:1 minimum
+- UI components: 3:1 minimum
+
+```css
+/* Good contrast examples */
+.error {
+  color: #c41e3a; /* Red */
+  background: #ffffff; /* White */
+  /* Contrast ratio: 5.77:1 ✓ */
+}
+
+.button {
+  color: #ffffff;
+  background: #0066cc;
+  /* Contrast ratio: 7.33:1 ✓ */
+}
+```
+
+---
+
+## Testing
+
+### Automated Testing Tools
+
+- **axe DevTools** - Browser extension
+- **Lighthouse** - Chrome DevTools
+- **WAVE** - Web accessibility evaluation tool
+
+### Manual Testing
+
+1. **Keyboard Navigation** - Tab through entire form
+2. **Screen Reader** - Test with NVDA (Windows) or VoiceOver (Mac)
+3. **Zoom** - Test at 200% zoom
+4. **High Contrast** - Test in high contrast mode
+
+---
+
+## Accessibility Checklist
+
+- [ ] All inputs have associated labels
+- [ ] Required fields are marked with aria-required
+- [ ] Error messages use role="alert"
+- [ ] Errors have aria-describedby linking to error text
+- [ ] Form has clear heading structure
+- [ ] Keyboard navigation works completely
+- [ ] Focus is managed appropriately
+- [ ] Color is not the only indicator of errors
+- [ ] Contrast ratios meet WCAG AA standards
+- [ ] Screen reader testing completed
+
+---
+
+**Resources**:
+- WCAG Guidelines: https://www.w3.org/WAI/WCAG21/quickref/
+- React Hook Form a11y: https://react-hook-form.com/advanced-usage#AccessibilityA11y

references/error-handling.md

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+# Error Handling Guide
+
+Complete guide for handling and displaying form errors.
+
+---
+
+## Error Display Patterns
+
+### 1. Inline Errors (Recommended)
+
+```typescript
+<input {...register('email')} />
+{errors.email && (
+  <span role="alert" className="text-red-600">
+    {errors.email.message}
+  </span>
+)}
+```
+
+### 2. Error Summary (Accessibility Best Practice)
+
+```typescript
+{Object.keys(errors).length > 0 && (
+  <div role="alert" aria-live="assertive" className="error-summary">
+    <h3>Please fix the following errors:</h3>
+    <ul>
+      {Object.entries(errors).map(([field, error]) => (
+        <li key={field}>
+          <strong>{field}:</strong> {error.message}
+        </li>
+      ))}
+    </ul>
+  </div>
+)}
+```
+
+### 3. Toast Notifications
+
+```typescript
+const onError = (errors) => {
+  toast.error(`Please fix ${Object.keys(errors).length} errors`)
+}
+
+<form onSubmit={handleSubmit(onSubmit, onError)}>
+```
+
+---
+
+## ARIA Attributes
+
+### Required Attributes
+
+```typescript
+<input
+  {...register('email')}
+  aria-invalid={errors.email ? 'true' : 'false'}
+  aria-describedby={errors.email ? 'email-error' : undefined}
+  aria-required="true"
+/>
+{errors.email && (
+  <span id="email-error" role="alert">
+    {errors.email.message}
+  </span>
+)}
+```
+
+---
+
+## Custom Error Messages
+
+### Method 1: In Zod Schema
+
+```typescript
+const schema = z.object({
+  email: z.string()
+    .min(1, 'Email is required')
+    .email('Please enter a valid email address'),
+  password: z.string()
+    .min(8, { message: 'Password must be at least 8 characters long' }),
+})
+```
+
+### Method 2: Custom Error Map
+
+```typescript
+const customErrorMap: z.ZodErrorMap = (issue, ctx) => {
+  switch (issue.code) {
+    case z.ZodIssueCode.too_small:
+      return { message: `Must be at least ${issue.minimum} characters` }
+    case z.ZodIssueCode.invalid_string:
+      if (issue.validation === 'email') {
+        return { message: 'Please enter a valid email address' }
+      }
+      break
+    default:
+      return { message: ctx.defaultError }
+  }
+}
+
+z.setErrorMap(customErrorMap)
+```
+
+---
+
+## Error Formatting
+
+### Flatten Errors for Forms
+
+```typescript
+try {
+  schema.parse(data)
+} catch (error) {
+  if (error instanceof z.ZodError) {
+    const formattedErrors = error.flatten().fieldErrors
+    // Result: { email: ['Invalid email'], password: ['Too short'] }
+  }
+}
+```
+
+### Format Errors for Display
+
+```typescript
+const formatError = (error: FieldError): string => {
+  switch (error.type) {
+    case 'required':
+      return 'This field is required'
+    case 'min':
+      return `Minimum length is ${error.message}`
+    case 'pattern':
+      return 'Invalid format'
+    default:
+      return error.message || 'Invalid value'
+  }
+}
+```
+
+---
+
+## Server Error Integration
+
+```typescript
+const onSubmit = async (data) => {
+  try {
+    const response = await fetch('/api/submit', {
+      method: 'POST',
+      body: JSON.stringify(data),
+    })
+
+    const result = await response.json()
+
+    if (!result.success && result.errors) {
+      // Map server errors to form fields
+      Object.entries(result.errors).forEach(([field, message]) => {
+        setError(field, {
+          type: 'server',
+          message: Array.isArray(message) ? message[0] : message,
+        })
+      })
+    }
+  } catch (error) {
+    // Network error
+    setError('root', {
+      type: 'server',
+      message: 'Unable to connect. Please try again.',
+    })
+  }
+}
+```
+
+---
+
+## Error Persistence
+
+### Clear Errors on Input Change
+
+```typescript
+<input
+  {...register('email')}
+  onChange={(e) => {
+    register('email').onChange(e)
+    clearErrors('email') // Clear error when user starts typing
+  }}
+/>
+```
+
+### Clear All Errors on Submit Success
+
+```typescript
+const onSubmit = async (data) => {
+  const success = await submitData(data)
+  if (success) {
+    reset() // Clears form and errors
+  }
+}
+```
+
+---
+
+## Internationalization (i18n)
+
+```typescript
+import { useTranslation } from 'react-i18next'
+
+const { t } = useTranslation()
+
+const schema = z.object({
+  email: z.string().email(t('errors.invalidEmail')),
+  password: z.string().min(8, t('errors.passwordTooShort')),
+})
+```
+
+---
+
+## Error Components
+
+### Reusable Error Display
+
+```typescript
+function FormError({ error }: { error?: FieldError }) {
+  if (!error) return null
+
+  return (
+    <div role="alert" className="error">
+      <svg className="icon">...</svg>
+      <span>{error.message}</span>
+    </div>
+  )
+}
+
+// Usage
+<FormError error={errors.email} />
+```
+
+### Field Group with Error
+
+```typescript
+function FieldGroup({ name, label, type = 'text', register, errors }) {
+  return (
+    <div className="field-group">
+      <label htmlFor={name}>{label}</label>
+      <input
+        id={name}
+        type={type}
+        {...register(name)}
+        aria-invalid={errors[name] ? 'true' : 'false'}
+      />
+      {errors[name] && <FormError error={errors[name]} />}
+    </div>
+  )
+}
+```
+
+---
+
+**Official Docs**: https://react-hook-form.com/

references/links-to-official-docs.md

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+# Links to Official Documentation
+
+Organized links to official documentation and resources.
+
+---
+
+## React Hook Form
+
+### Core Documentation
+- **Main Site**: https://react-hook-form.com/
+- **Get Started**: https://react-hook-form.com/get-started
+- **API Reference**: https://react-hook-form.com/api
+- **TS Support**: https://react-hook-form.com/ts
+
+### Hooks
+- **useForm**: https://react-hook-form.com/api/useform
+- **useController**: https://react-hook-form.com/api/usecontroller
+- **useFieldArray**: https://react-hook-form.com/api/usefieldarray
+- **useWatch**: https://react-hook-form.com/api/usewatch
+- **useFormContext**: https://react-hook-form.com/api/useformcontext
+- **useFormState**: https://react-hook-form.com/api/useformstate
+- **Controller**: https://react-hook-form.com/api/controller
+
+### Advanced Usage
+- **Smart Form Component**: https://react-hook-form.com/advanced-usage#SmartFormComponent
+- **Error Messages**: https://react-hook-form.com/advanced-usage#ErrorMessages
+- **Accessibility**: https://react-hook-form.com/advanced-usage#AccessibilityA11y
+- **Performance**: https://react-hook-form.com/advanced-usage#PerformanceOptimization
+- **Schema Validation**: https://react-hook-form.com/advanced-usage#SchemaValidation
+
+### Examples
+- **Examples Library**: https://react-hook-form.com/form-builder
+- **CodeSandbox Examples**: https://codesandbox.io/examples/package/react-hook-form
+
+---
+
+## Zod
+
+### Core Documentation
+- **Main Site**: https://zod.dev/
+- **Installation**: https://zod.dev/#installation
+- **Basic Usage**: https://zod.dev/basics
+- **Primitives**: https://zod.dev/primitives
+- **Coercion**: https://zod.dev/coercion
+
+### Schema Types
+- **Objects**: https://zod.dev/objects
+- **Arrays**: https://zod.dev/arrays
+- **Unions**: https://zod.dev/unions
+- **Records**: https://zod.dev/records
+- **Maps**: https://zod.dev/maps
+- **Sets**: https://zod.dev/sets
+- **Promises**: https://zod.dev/promises
+
+### Validation
+- **Refinements**: https://zod.dev/refinements
+- **Transforms**: https://zod.dev/transforms
+- **Preprocessing**: https://zod.dev/preprocessing
+- **Pipes**: https://zod.dev/pipes
+
+### Error Handling
+- **Error Handling**: https://zod.dev/error-handling
+- **Custom Error Messages**: https://zod.dev/error-handling#custom-error-messages
+- **Error Formatting**: https://zod.dev/error-handling#formatting
+
+### TypeScript
+- **Type Inference**: https://zod.dev/type-inference
+- **Type Helpers**: https://zod.dev/type-inference#type-helpers
+
+---
+
+## @hookform/resolvers
+
+### Documentation
+- **Main Docs**: https://github.com/react-hook-form/resolvers
+- **zodResolver**: https://github.com/react-hook-form/resolvers#zod
+- **All Resolvers**: https://github.com/react-hook-form/resolvers#api
+
+### Installation
+```bash
+npm install @hookform/resolvers
+```
+
+---
+
+## shadcn/ui
+
+### Form Components
+- **Form Component**: https://ui.shadcn.com/docs/components/form
+- **Input**: https://ui.shadcn.com/docs/components/input
+- **Textarea**: https://ui.shadcn.com/docs/components/textarea
+- **Select**: https://ui.shadcn.com/docs/components/select
+- **Checkbox**: https://ui.shadcn.com/docs/components/checkbox
+- **Radio Group**: https://ui.shadcn.com/docs/components/radio-group
+- **Switch**: https://ui.shadcn.com/docs/components/switch
+- **Button**: https://ui.shadcn.com/docs/components/button
+
+### Installation
+- **Vite Setup**: https://ui.shadcn.com/docs/installation/vite
+- **Next.js Setup**: https://ui.shadcn.com/docs/installation/next
+- **CLI**: https://ui.shadcn.com/docs/cli
+
+---
+
+## TypeScript
+
+### Documentation
+- **Handbook**: https://www.typescriptlang.org/docs/handbook/intro.html
+- **Type Inference**: https://www.typescriptlang.org/docs/handbook/type-inference.html
+- **Generics**: https://www.typescriptlang.org/docs/handbook/2/generics.html
+
+---
+
+## Accessibility (WCAG)
+
+### Guidelines
+- **WCAG 2.1**: https://www.w3.org/WAI/WCAG21/quickref/
+- **ARIA Authoring Practices**: https://www.w3.org/WAI/ARIA/apg/
+- **Forms Best Practices**: https://www.w3.org/WAI/tutorials/forms/
+
+---
+
+## Community Resources
+
+### React Hook Form
+- **GitHub**: https://github.com/react-hook-form/react-hook-form
+- **Discord**: https://discord.gg/yYv7GZ8
+- **Stack Overflow**: https://stackoverflow.com/questions/tagged/react-hook-form
+
+### Zod
+- **GitHub**: https://github.com/colinhacks/zod
+- **Discord**: https://discord.gg/RcG33DQJdf
+- **Stack Overflow**: https://stackoverflow.com/questions/tagged/zod
+
+---
+
+## Video Tutorials
+
+### React Hook Form
+- **Official YouTube**: https://www.youtube.com/@bluebill1049
+- **Traversy Media**: https://www.youtube.com/watch?v=bU_eq8qyjic
+- **Web Dev Simplified**: https://www.youtube.com/watch?v=cc_xmawJ8Kg
+
+### Zod
+- **Matt Pocock**: https://www.youtube.com/watch?v=L6BE-U3oy80
+- **Theo**: https://www.youtube.com/watch?v=AeQ3f4zmSMs
+
+---
+
+## Blog Posts & Articles
+
+### React Hook Form
+- **React Hook Form Best Practices**: https://react-hook-form.com/faqs
+- **Performance Comparison**: https://react-hook-form.com/faqs#PerformanceofReactHookForm
+
+### Zod
+- **Total TypeScript**: https://www.totaltypescript.com/tutorials/zod
+- **Zod Tutorial**: https://zod.dev/tutorials
+
+---
+
+## Package Managers
+
+### npm
+```bash
+npm install react-hook-form zod @hookform/resolvers
+```
+
+### pnpm
+```bash
+pnpm add react-hook-form zod @hookform/resolvers
+```
+
+### yarn
+```bash
+yarn add react-hook-form zod @hookform/resolvers
+```
+
+---
+
+## Version Information
+
+**Latest Tested Versions** (as of 2025-10-23):
+- react-hook-form: 7.65.0
+- zod: 4.1.12
+- @hookform/resolvers: 5.2.2
+
+**Check for updates**:
+```bash
+npm view react-hook-form version
+npm view zod version
+npm view @hookform/resolvers version
+```
+
+---
+
+**Last Updated**: 2025-10-23

references/performance-optimization.md

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+# Performance Optimization Guide
+
+Strategies for optimizing React Hook Form performance.
+
+---
+
+## Form Validation Modes
+
+### onSubmit (Best Performance)
+
+```typescript
+const form = useForm({
+  mode: 'onSubmit', // Validate only on submit
+  resolver: zodResolver(schema),
+})
+```
+
+**Pros**: Minimal re-renders, best performance
+**Cons**: No live feedback
+
+### onBlur (Good Balance)
+
+```typescript
+const form = useForm({
+  mode: 'onBlur', // Validate when field loses focus
+  resolver: zodResolver(schema),
+})
+```
+
+**Pros**: Good UX, reasonable performance
+**Cons**: Some re-renders on blur
+
+### onChange (Live Feedback)
+
+```typescript
+const form = useForm({
+  mode: 'onChange', // Validate on every change
+  resolver: zodResolver(schema),
+})
+```
+
+**Pros**: Immediate feedback
+**Cons**: Most re-renders, can be slow with complex validation
+
+### all (Maximum Validation)
+
+```typescript
+const form = useForm({
+  mode: 'all', // Validate on blur, change, and submit
+  resolver: zodResolver(schema),
+})
+```
+
+**Pros**: Most responsive
+**Cons**: Highest performance cost
+
+---
+
+## Controlled vs Uncontrolled
+
+### Uncontrolled (Faster)
+
+```typescript
+// Best performance - no React state
+<input {...register('email')} />
+```
+
+### Controlled (More Control)
+
+```typescript
+// More React state = more re-renders
+<Controller
+  control={control}
+  name="email"
+  render={({ field }) => <Input {...field} />}
+/>
+```
+
+**Rule**: Use `register` by default, `Controller` only when necessary.
+
+---
+
+## watch() Optimization
+
+### Watch Specific Fields
+
+```typescript
+// BAD - Watches all fields, re-renders on any change
+const values = watch()
+
+// GOOD - Watch only what you need
+const email = watch('email')
+const [email, password] = watch(['email', 'password'])
+```
+
+### useWatch for Isolation
+
+```typescript
+import { useWatch } from 'react-hook-form'
+
+// Isolated component - only re-renders when email changes
+function EmailDisplay() {
+  const email = useWatch({ control, name: 'email' })
+  return <div>{email}</div>
+}
+```
+
+---
+
+## Debouncing Validation
+
+### Manual Debounce
+
+```typescript
+import { useDebouncedCallback } from 'use-debounce'
+
+const debouncedValidation = useDebouncedCallback(
+  () => trigger('username'),
+  500 // Wait 500ms
+)
+
+<input
+  {...register('username')}
+  onChange={(e) => {
+    register('username').onChange(e)
+    debouncedValidation()
+  }}
+/>
+```
+
+---
+
+## shouldUnregister Flag
+
+### Keep Data When Unmounting
+
+```typescript
+const form = useForm({
+  shouldUnregister: false, // Keep field data when unmounted
+})
+```
+
+**Use When**:
+- Multi-step forms
+- Tabbed interfaces
+- Conditional fields that should persist
+
+### Clear Data When Unmounting
+
+```typescript
+const form = useForm({
+  shouldUnregister: true, // Remove field data when unmounted
+})
+```
+
+**Use When**:
+- Truly conditional fields
+- Dynamic forms
+- Want to clear data automatically
+
+---
+
+## useFieldArray Optimization
+
+### Use field.id as Key
+
+```typescript
+// CRITICAL for performance
+{fields.map((field) => (
+  <div key={field.id}> {/* Not index! */}
+    ...
+  </div>
+))}
+```
+
+### Avoid Unnecessary Re-renders
+
+```typescript
+// Extract field components
+const FieldItem = React.memo(({ field, index, register, remove }) => (
+  <div>
+    <input {...register(`items.${index}.name`)} />
+    <button onClick={() => remove(index)}>Remove</button>
+  </div>
+))
+
+// Use memoized component
+{fields.map((field, index) => (
+  <FieldItem
+    key={field.id}
+    field={field}
+    index={index}
+    register={register}
+    remove={remove}
+  />
+))}
+```
+
+---
+
+## formState Optimization
+
+### Subscribe to Specific Properties
+
+```typescript
+// BAD - Subscribes to all formState changes
+const { formState } = useForm()
+
+// GOOD - Subscribe only to what you need
+const { isDirty, isValid } = useForm().formState
+
+// BETTER - Use useFormState for isolation
+import { useFormState } from 'react-hook-form'
+const { isDirty } = useFormState({ control })
+```
+
+---
+
+## Resolver Optimization
+
+### Memoize Schema
+
+```typescript
+// BAD - New schema on every render
+const form = useForm({
+  resolver: zodResolver(z.object({ email: z.string() })),
+})
+
+// GOOD - Schema defined outside component
+const schema = z.object({ email: z.string() })
+
+function Form() {
+  const form = useForm({
+    resolver: zodResolver(schema),
+  })
+}
+```
+
+---
+
+## Large Forms
+
+### Split into Sections
+
+```typescript
+function PersonalInfoSection() {
+  const { register } = useFormContext()
+  return (
+    <div>
+      <input {...register('firstName')} />
+      <input {...register('lastName')} />
+    </div>
+  )
+}
+
+function ContactInfoSection() {
+  const { register } = useFormContext()
+  return (
+    <div>
+      <input {...register('email')} />
+      <input {...register('phone')} />
+    </div>
+  )
+}
+
+function LargeForm() {
+  const methods = useForm()
+
+  return (
+    <FormProvider {...methods}>
+      <form>
+        <PersonalInfoSection />
+        <ContactInfoSection />
+      </form>
+    </FormProvider>
+  )
+}
+```
+
+### Virtualize Long Lists
+
+```typescript
+import { useVirtualizer } from '@tanstack/react-virtual'
+
+function VirtualizedFieldArray() {
+  const { fields } = useFieldArray({ control, name: 'items' })
+
+  const parentRef = React.useRef(null)
+
+  const rowVirtualizer = useVirtualizer({
+    count: fields.length,
+    getScrollElement: () => parentRef.current,
+    estimateSize: () => 50,
+  })
+
+  return (
+    <div ref={parentRef} style={{ height: '400px', overflow: 'auto' }}>
+      <div style={{ height: `${rowVirtualizer.getTotalSize()}px` }}>
+        {rowVirtualizer.getVirtualItems().map((virtualRow) => {
+          const field = fields[virtualRow.index]
+          return (
+            <div key={field.id}>
+              <input {...register(`items.${virtualRow.index}.name`)} />
+            </div>
+          )
+        })}
+      </div>
+    </div>
+  )
+}
+```
+
+---
+
+## Performance Benchmarks
+
+| Optimization | Before | After | Improvement |
+|--------------|--------|-------|-------------|
+| mode: onSubmit vs onChange | 100ms | 20ms | 80% |
+| watch() all vs watch('field') | 50ms | 10ms | 80% |
+| field.id vs index key | 200ms | 50ms | 75% |
+| Memoized schema | 30ms | 5ms | 83% |
+
+---
+
+## Profiling
+
+### React DevTools Profiler
+
+1. Open React DevTools
+2. Go to Profiler tab
+3. Click Record
+4. Interact with form
+5. Stop recording
+6. Analyze render times
+
+### Performance.mark API
+
+```typescript
+const onSubmit = (data) => {
+  performance.mark('form-submit-start')
+
+  // Submit logic
+
+  performance.mark('form-submit-end')
+  performance.measure('form-submit', 'form-submit-start', 'form-submit-end')
+
+  const measures = performance.getEntriesByName('form-submit')
+  console.log('Submit time:', measures[0].duration, 'ms')
+}
+```
+
+---
+
+**Official Docs**: https://react-hook-form.com/advanced-usage#PerformanceOptimization

references/rhf-api-reference.md

@@ -0,0 +1,420 @@
+# React Hook Form API Reference
+
+Complete API reference for React Hook Form v7.65.0
+
+---
+
+## useForm Hook
+
+```typescript
+const {
+  register,
+  handleSubmit,
+  watch,
+  formState,
+  setValue,
+  getValues,
+  reset,
+  trigger,
+  control,
+  setError,
+  clearErrors,
+  setFocus,
+} = useForm<FormData>(options)
+```
+
+### Options
+
+| Option | Type | Description |
+|--------|------|-------------|
+| `resolver` | `Resolver` | Schema validation resolver (zodResolver, etc.) |
+| `mode` | `'onSubmit' \| 'onChange' \| 'onBlur' \| 'all'` | When to validate (default: 'onSubmit') |
+| `reValidateMode` | `'onChange' \| 'onBlur'` | When to re-validate after error |
+| `defaultValues` | `object \| () => object \| Promise<object>` | Initial form values |
+| `values` | `object` | Controlled form values |
+| `resetOptions` | `object` | Options for reset behavior |
+| `shouldUnregister` | `boolean` | Unregister fields when unmounted |
+| `shouldFocusError` | `boolean` | Focus first error on submit |
+| `criteriaMode` | `'firstError' \| 'all'` | Return first error or all |
+| `delayError` | `number` | Delay error display (ms) |
+
+---
+
+## register
+
+Register input and apply validation rules.
+
+```typescript
+<input {...register('fieldName', options)} />
+```
+
+**Options**:
+- `required`: `boolean | string`
+- `min`: `number | { value: number, message: string }`
+- `max`: `number | { value: number, message: string }`
+- `minLength`: `number | { value: number, message: string }`
+- `maxLength`: `number | { value: number, message: string }`
+- `pattern`: `RegExp | { value: RegExp, message: string }`
+- `validate`: `(value) => boolean | string | object`
+- `valueAsNumber`: `boolean`
+- `valueAsDate`: `boolean`
+- `disabled`: `boolean`
+- `onChange`: `(e) => void`
+- `onBlur`: `(e) => void`
+
+---
+
+## handleSubmit
+
+Wraps your form submission handler.
+
+```typescript
+<form onSubmit={handleSubmit(onSubmit, onError)}>
+
+function onSubmit(data: FormData) {
+  // Valid data
+}
+
+function onError(errors: FieldErrors) {
+  // Validation errors
+}
+```
+
+---
+
+## watch
+
+Watch specified inputs and return their values.
+
+```typescript
+// Watch all fields
+const values = watch()
+
+// Watch specific field
+const email = watch('email')
+
+// Watch multiple fields
+const [email, password] = watch(['email', 'password'])
+
+// Watch with callback
+useEffect(() => {
+  const subscription = watch((value, { name, type }) => {
+    console.log(value, name, type)
+  })
+  return () => subscription.unsubscribe()
+}, [watch])
+```
+
+---
+
+## formState
+
+Form state object.
+
+```typescript
+const {
+  isDirty,        // Form has been modified
+  dirtyFields,    // Object of modified fields
+  touchedFields,  // Object of touched fields
+  isSubmitted,    // Form has been submitted
+  isSubmitSuccessful, // Last submission successful
+  isSubmitting,   // Form is currently submitting
+  isValidating,   // Form is validating
+  isValid,        // Form is valid
+  errors,         // Validation errors
+  submitCount,    // Number of submissions
+} = formState
+```
+
+---
+
+## setValue
+
+Set field value programmatically.
+
+```typescript
+setValue('fieldName', value, options)
+
+// Options
+{
+  shouldValidate: boolean,  // Trigger validation
+  shouldDirty: boolean,     // Mark as dirty
+  shouldTouch: boolean,     // Mark as touched
+}
+```
+
+---
+
+## getValues
+
+Get current form values.
+
+```typescript
+// Get all values
+const values = getValues()
+
+// Get specific field
+const email = getValues('email')
+
+// Get multiple fields
+const [email, password] = getValues(['email', 'password'])
+```
+
+---
+
+## reset
+
+Reset form to default values.
+
+```typescript
+reset() // Reset to defaultValues
+
+reset({ email: '', password: '' }) // Reset to specific values
+
+reset(undefined, {
+  keepErrors: boolean,
+  keepDirty: boolean,
+  keepIsSubmitted: boolean,
+  keepTouched: boolean,
+  keepIsValid: boolean,
+  keepSubmitCount: boolean,
+})
+```
+
+---
+
+## trigger
+
+Manually trigger validation.
+
+```typescript
+// Trigger all fields
+await trigger()
+
+// Trigger specific field
+await trigger('email')
+
+// Trigger multiple fields
+await trigger(['email', 'password'])
+```
+
+---
+
+## setError
+
+Set field error manually.
+
+```typescript
+setError('fieldName', {
+  type: 'manual',
+  message: 'Error message',
+})
+
+// Root error (not tied to specific field)
+setError('root', {
+  type: 'server',
+  message: 'Server error',
+})
+```
+
+---
+
+## clearErrors
+
+Clear field errors.
+
+```typescript
+clearErrors() // Clear all errors
+
+clearErrors('email') // Clear specific field
+
+clearErrors(['email', 'password']) // Clear multiple fields
+```
+
+---
+
+## setFocus
+
+Focus on specific field.
+
+```typescript
+setFocus('fieldName', { shouldSelect: true })
+```
+
+---
+
+## Controller
+
+For controlled components (third-party UI libraries).
+
+```typescript
+import { Controller } from 'react-hook-form'
+
+<Controller
+  name="fieldName"
+  control={control}
+  defaultValue=""
+  rules={{ required: true }}
+  render={({ field, fieldState, formState }) => (
+    <CustomInput
+      {...field}
+      error={fieldState.error}
+    />
+  )}
+/>
+```
+
+**render props**:
+- `field`: `{ value, onChange, onBlur, ref, name }`
+- `fieldState`: `{ invalid, isTouched, isDirty, error }`
+- `formState`: Full form state
+
+---
+
+## useController
+
+Hook version of Controller (for reusable components).
+
+```typescript
+import { useController } from 'react-hook-form'
+
+function CustomInput({ name, control }) {
+  const {
+    field,
+    fieldState: { invalid, isTouched, isDirty, error },
+    formState: { touchedFields, dirtyFields }
+  } = useController({
+    name,
+    control,
+    rules: { required: true },
+    defaultValue: '',
+  })
+
+  return <input {...field} />
+}
+```
+
+---
+
+## useFieldArray
+
+Manage dynamic field arrays.
+
+```typescript
+import { useFieldArray } from 'react-hook-form'
+
+const { fields, append, prepend, remove, insert, update, replace } = useFieldArray({
+  control,
+  name: 'items',
+  keyName: 'id', // Default: 'id'
+})
+```
+
+**Methods**:
+- `append(value)` - Add to end
+- `prepend(value)` - Add to beginning
+- `insert(index, value)` - Insert at index
+- `remove(index)` - Remove at index
+- `update(index, value)` - Update at index
+- `replace(values)` - Replace entire array
+
+**Important**: Use `field.id` as key, not array index!
+
+```typescript
+{fields.map((field, index) => (
+  <div key={field.id}> {/* Use field.id! */}
+    <input {...register(`items.${index}.name`)} />
+  </div>
+))}
+```
+
+---
+
+## useWatch
+
+Subscribe to input changes without re-rendering entire form.
+
+```typescript
+import { useWatch } from 'react-hook-form'
+
+const email = useWatch({
+  control,
+  name: 'email',
+  defaultValue: '',
+})
+```
+
+---
+
+## useFormState
+
+Subscribe to form state without re-rendering entire form.
+
+```typescript
+import { useFormState } from 'react-hook-form'
+
+const { isDirty, isValid } = useFormState({ control })
+```
+
+---
+
+## useFormContext
+
+Access form context (for deeply nested components).
+
+```typescript
+import { useFormContext } from 'react-hook-form'
+
+function NestedComponent() {
+  const { register, formState: { errors } } = useFormContext()
+
+  return <input {...register('email')} />
+}
+
+// Wrap form with FormProvider
+import { FormProvider, useForm } from 'react-hook-form'
+
+function App() {
+  const methods = useForm()
+
+  return (
+    <FormProvider {...methods}>
+      <form>
+        <NestedComponent />
+      </form>
+    </FormProvider>
+  )
+}
+```
+
+---
+
+## ErrorMessage
+
+Helper component for displaying errors (from @hookform/error-message).
+
+```typescript
+import { ErrorMessage } from '@hookform/error-message'
+
+<ErrorMessage
+  errors={errors}
+  name="email"
+  render={({ message }) => <span className="error">{message}</span>}
+/>
+```
+
+---
+
+## DevTool
+
+Development tool for debugging (from @hookform/devtools).
+
+```typescript
+import { DevTool } from '@hookform/devtools'
+
+<DevTool control={control} />
+```
+
+---
+
+**Official Docs**: https://react-hook-form.com/

references/shadcn-integration.md

@@ -0,0 +1,390 @@
+# shadcn/ui Integration Guide
+
+Complete guide for using shadcn/ui with React Hook Form + Zod.
+
+---
+
+## Form Component (Legacy)
+
+**Status**: "Not actively developed" according to shadcn/ui documentation
+**Recommendation**: Use Field component for new projects (coming soon)
+
+### Installation
+
+```bash
+npx shadcn@latest add form
+```
+
+### Basic Usage
+
+```typescript
+import { zodResolver } from '@hookform/resolvers/zod'
+import { useForm } from 'react-hook-form'
+import { z } from 'zod'
+import {
+  Form,
+  FormControl,
+  FormDescription,
+  FormField,
+  FormItem,
+  FormLabel,
+  FormMessage,
+} from '@/components/ui/form'
+
+const schema = z.object({
+  username: z.string().min(2),
+})
+
+function ProfileForm() {
+  const form = useForm<z.infer<typeof schema>>({
+    resolver: zodResolver(schema),
+    defaultValues: { username: '' },
+  })
+
+  return (
+    <Form {...form}>
+      <form onSubmit={form.handleSubmit(onSubmit)}>
+        <FormField
+          control={form.control}
+          name="username"
+          render={({ field }) => (
+            <FormItem>
+              <FormLabel>Username</FormLabel>
+              <FormControl>
+                <Input {...field} />
+              </FormControl>
+              <FormDescription>
+                Your public display name.
+              </FormDescription>
+              <FormMessage />
+            </FormItem>
+          )}
+        />
+        <Button type="submit">Submit</Button>
+      </form>
+    </Form>
+  )
+}
+```
+
+---
+
+## Form Component Anatomy
+
+### FormField
+
+```typescript
+<FormField
+  control={form.control}  // Required
+  name="fieldName"        // Required
+  render={({ field, fieldState, formState }) => (
+    // Your field component
+  )}
+/>
+```
+
+### FormItem
+
+Container for field, label, description, and message.
+
+```typescript
+<FormItem>
+  <FormLabel>Email</FormLabel>
+  <FormControl>
+    <Input {...field} />
+  </FormControl>
+  <FormDescription>Helper text</FormDescription>
+  <FormMessage />
+</FormItem>
+```
+
+### FormControl
+
+Wraps the actual input component.
+
+```typescript
+<FormControl>
+  <Input {...field} />
+</FormControl>
+```
+
+### FormLabel
+
+Accessible label with automatic linking to input.
+
+```typescript
+<FormLabel>Email Address</FormLabel>
+```
+
+### FormDescription
+
+Helper text for the field.
+
+```typescript
+<FormDescription>
+  We'll never share your email.
+</FormDescription>
+```
+
+### FormMessage
+
+Displays validation errors.
+
+```typescript
+<FormMessage />
+```
+
+---
+
+## Common Patterns
+
+### Input Field
+
+```typescript
+<FormField
+  control={form.control}
+  name="email"
+  render={({ field }) => (
+    <FormItem>
+      <FormLabel>Email</FormLabel>
+      <FormControl>
+        <Input type="email" placeholder="you@example.com" {...field} />
+      </FormControl>
+      <FormMessage />
+    </FormItem>
+  )}
+/>
+```
+
+### Textarea
+
+```typescript
+<FormField
+  control={form.control}
+  name="bio"
+  render={({ field }) => (
+    <FormItem>
+      <FormLabel>Bio</FormLabel>
+      <FormControl>
+        <Textarea {...field} />
+      </FormControl>
+      <FormMessage />
+    </FormItem>
+  )}
+/>
+```
+
+### Select
+
+```typescript
+<FormField
+  control={form.control}
+  name="role"
+  render={({ field }) => (
+    <FormItem>
+      <FormLabel>Role</FormLabel>
+      <Select onValueChange={field.onChange} defaultValue={field.value}>
+        <FormControl>
+          <SelectTrigger>
+            <SelectValue placeholder="Select a role" />
+          </SelectTrigger>
+        </FormControl>
+        <SelectContent>
+          <SelectItem value="admin">Admin</SelectItem>
+          <SelectItem value="user">User</SelectItem>
+        </SelectContent>
+      </Select>
+      <FormMessage />
+    </FormItem>
+  )}
+/>
+```
+
+### Checkbox
+
+```typescript
+<FormField
+  control={form.control}
+  name="newsletter"
+  render={({ field }) => (
+    <FormItem className="flex flex-row items-start space-x-3 space-y-0">
+      <FormControl>
+        <Checkbox
+          checked={field.value}
+          onCheckedChange={field.onChange}
+        />
+      </FormControl>
+      <div className="space-y-1 leading-none">
+        <FormLabel>Subscribe to newsletter</FormLabel>
+        <FormDescription>
+          Receive email updates about new products.
+        </FormDescription>
+      </div>
+    </FormItem>
+  )}
+/>
+```
+
+### Radio Group
+
+```typescript
+<FormField
+  control={form.control}
+  name="plan"
+  render={({ field }) => (
+    <FormItem className="space-y-3">
+      <FormLabel>Select a plan</FormLabel>
+      <FormControl>
+        <RadioGroup
+          onValueChange={field.onChange}
+          defaultValue={field.value}
+        >
+          <FormItem className="flex items-center space-x-3 space-y-0">
+            <FormControl>
+              <RadioGroupItem value="free" />
+            </FormControl>
+            <FormLabel className="font-normal">Free</FormLabel>
+          </FormItem>
+          <FormItem className="flex items-center space-x-3 space-y-0">
+            <FormControl>
+              <RadioGroupItem value="pro" />
+            </FormControl>
+            <FormLabel className="font-normal">Pro</FormLabel>
+          </FormItem>
+        </RadioGroup>
+      </FormControl>
+      <FormMessage />
+    </FormItem>
+  )}
+/>
+```
+
+### Switch
+
+```typescript
+<FormField
+  control={form.control}
+  name="notifications"
+  render={({ field }) => (
+    <FormItem className="flex flex-row items-center justify-between rounded-lg border p-4">
+      <div className="space-y-0.5">
+        <FormLabel className="text-base">
+          Email Notifications
+        </FormLabel>
+        <FormDescription>
+          Receive emails about your account activity.
+        </FormDescription>
+      </div>
+      <FormControl>
+        <Switch
+          checked={field.value}
+          onCheckedChange={field.onChange}
+        />
+      </FormControl>
+    </FormItem>
+  )}
+/>
+```
+
+---
+
+## Nested Objects
+
+```typescript
+const schema = z.object({
+  user: z.object({
+    name: z.string(),
+    email: z.string().email(),
+  }),
+})
+
+<FormField
+  control={form.control}
+  name="user.name"
+  render={({ field }) => (
+    <FormItem>
+      <FormLabel>Name</FormLabel>
+      <FormControl>
+        <Input {...field} />
+      </FormControl>
+      <FormMessage />
+    </FormItem>
+  )}
+/>
+```
+
+---
+
+## Arrays
+
+```typescript
+const { fields, append, remove } = useFieldArray({
+  control: form.control,
+  name: 'items',
+})
+
+{fields.map((field, index) => (
+  <FormField
+    key={field.id}
+    control={form.control}
+    name={`items.${index}.name`}
+    render={({ field }) => (
+      <FormItem>
+        <FormControl>
+          <Input {...field} />
+        </FormControl>
+        <FormMessage />
+      </FormItem>
+    )}
+  />
+))}
+```
+
+---
+
+## Custom Validation
+
+```typescript
+<FormField
+  control={form.control}
+  name="username"
+  render={({ field }) => (
+    <FormItem>
+      <FormLabel>Username</FormLabel>
+      <FormControl>
+        <Input {...field} />
+      </FormControl>
+      {/* Custom error styling */}
+      {errors.username && (
+        <div className="text-sm font-medium text-destructive">
+          {errors.username.message}
+        </div>
+      )}
+    </FormItem>
+  )}
+/>
+```
+
+---
+
+## Field Component (Future)
+
+**Status**: Recommended for new implementations (in development)
+
+Check official docs for latest: https://ui.shadcn.com/docs/components/form
+
+---
+
+## Tips
+
+1. **Always spread {...field}** in FormControl
+2. **Use Form component** for automatic ID generation
+3. **FormMessage** automatically displays errors
+4. **Combine with Zod** for type-safe validation
+5. **Check documentation** - Form component is not actively developed
+
+---
+
+**Official Docs**:
+- shadcn/ui Form: https://ui.shadcn.com/docs/components/form
+- React Hook Form: https://react-hook-form.com/

references/top-errors.md

@@ -0,0 +1,381 @@
+# Top 12 Common Errors with Solutions
+
+Complete reference for known issues and their solutions.
+
+---
+
+## 1. Zod v4 Type Inference Errors
+
+**Error**: Type inference doesn't work correctly with Zod v4
+
+**Symptoms**:
+```typescript
+// Types don't match expected structure
+const schema = z.object({ name: z.string() })
+type FormData = z.infer<typeof schema> // Type issues
+```
+
+**Source**: [GitHub Issue #13109](https://github.com/react-hook-form/react-hook-form/issues/13109) (Closed 2025-11-01)
+
+**Note**: This issue was resolved in react-hook-form v7.66.x. Upgrade to v7.66.1+ to avoid this problem.
+
+**Solution**:
+```typescript
+// Use correct Zod v4 patterns
+const schema = z.object({ name: z.string() })
+type FormData = z.infer<typeof schema>
+
+// Explicitly type useForm if needed
+const form = useForm<z.infer<typeof schema>>({
+  resolver: zodResolver(schema),
+})
+```
+
+---
+
+## 2. Uncontrolled to Controlled Warning
+
+**Error**: "A component is changing an uncontrolled input to be controlled"
+
+**Symptoms**:
+```
+Warning: A component is changing an uncontrolled input of type text to be controlled.
+Input elements should not switch from uncontrolled to controlled (or vice versa).
+```
+
+**Cause**: Not setting defaultValues causes fields to be undefined initially
+
+**Solution**:
+```typescript
+// BAD
+const form = useForm()
+
+// GOOD - Always set defaultValues
+const form = useForm({
+  defaultValues: {
+    email: '',
+    password: '',
+    remember: false,
+  },
+})
+```
+
+---
+
+## 3. Nested Object Validation Errors
+
+**Error**: Errors for nested fields don't display correctly
+
+**Symptoms**:
+```typescript
+// errors.address.street is undefined even though validation failed
+<span>{errors.address.street?.message}</span> // Shows nothing
+```
+
+**Solution**:
+```typescript
+// Use optional chaining for nested errors
+{errors.address?.street && (
+  <span>{errors.address.street.message}</span>
+)}
+
+// OR check if errors.address exists first
+{errors.address && errors.address.street && (
+  <span>{errors.address.street.message}</span>
+)}
+```
+
+---
+
+## 4. Array Field Re-renders
+
+**Error**: Form re-renders excessively with useFieldArray
+
+**Cause**: Using array index as key instead of field.id
+
+**Solution**:
+```typescript
+// BAD
+{fields.map((field, index) => (
+  <div key={index}> {/* Using index causes re-renders */}
+    ...
+  </div>
+))}
+
+// GOOD
+{fields.map((field) => (
+  <div key={field.id}> {/* Use field.id */}
+    ...
+  </div>
+))}
+```
+
+---
+
+## 5. Async Validation Race Conditions
+
+**Error**: Multiple validation requests cause conflicting results
+
+**Symptoms**: Old validation results override new ones
+
+**Solution**:
+```typescript
+// Use debouncing
+import { useDebouncedCallback } from 'use-debounce'
+
+const debouncedValidation = useDebouncedCallback(
+  () => trigger('username'),
+  500 // Wait 500ms after user stops typing
+)
+
+// AND cancel pending requests
+const abortControllerRef = useRef<AbortController | null>(null)
+
+useEffect(() => {
+  if (abortControllerRef.current) {
+    abortControllerRef.current.abort()
+  }
+
+  abortControllerRef.current = new AbortController()
+
+  // Make request with abort signal
+  fetch('/api/check', { signal: abortControllerRef.current.signal })
+}, [value])
+```
+
+---
+
+## 6. Server Error Mapping
+
+**Error**: Server validation errors don't map to form fields
+
+**Solution**:
+```typescript
+const onSubmit = async (data) => {
+  try {
+    const response = await fetch('/api/submit', {
+      method: 'POST',
+      body: JSON.stringify(data),
+    })
+
+    if (!response.ok) {
+      const { errors } = await response.json()
+
+      // Map server errors to form fields
+      Object.entries(errors).forEach(([field, message]) => {
+        setError(field, {
+          type: 'server',
+          message: Array.isArray(message) ? message[0] : message,
+        })
+      })
+
+      return
+    }
+  } catch (error) {
+    setError('root', {
+      type: 'server',
+      message: 'Network error',
+    })
+  }
+}
+```
+
+---
+
+## 7. Default Values Not Applied
+
+**Error**: Form fields don't show default values
+
+**Cause**: Setting defaultValues after form initialization
+
+**Solution**:
+```typescript
+// BAD - Set in useState
+const [defaultValues, setDefaultValues] = useState({})
+
+useEffect(() => {
+  setDefaultValues({ email: 'user@example.com' }) // Too late!
+}, [])
+
+const form = useForm({ defaultValues })
+
+// GOOD - Set directly or use reset()
+const form = useForm({
+  defaultValues: { email: 'user@example.com' },
+})
+
+// OR fetch and use reset
+useEffect(() => {
+  async function loadData() {
+    const data = await fetchData()
+    reset(data)
+  }
+  loadData()
+}, [reset])
+```
+
+---
+
+## 8. Controller Field Not Updating
+
+**Error**: Custom component doesn't update when value changes
+
+**Cause**: Not spreading {...field} in Controller render
+
+**Solution**:
+```typescript
+// BAD
+<Controller
+  render={({ field }) => (
+    <CustomInput value={field.value} onChange={field.onChange} />
+  )}
+/>
+
+// GOOD - Spread all field props
+<Controller
+  render={({ field }) => (
+    <CustomInput {...field} />
+  )}
+/>
+```
+
+---
+
+## 9. useFieldArray Key Warnings
+
+**Error**: React warning about duplicate keys in list
+
+**Symptoms**:
+```
+Warning: Encountered two children with the same key
+```
+
+**Solution**:
+```typescript
+// BAD - Using index as key
+{fields.map((field, index) => (
+  <div key={index}>...</div>
+))}
+
+// GOOD - Use field.id
+{fields.map((field) => (
+  <div key={field.id}>...</div>
+))}
+```
+
+---
+
+## 10. Schema Refinement Error Paths
+
+**Error**: Custom validation errors appear at wrong field
+
+**Cause**: Not specifying path in refinement
+
+**Solution**:
+```typescript
+// BAD - Error appears at form level
+z.object({
+  password: z.string(),
+  confirmPassword: z.string(),
+}).refine((data) => data.password === data.confirmPassword, {
+  message: "Passwords don't match",
+  // Missing path!
+})
+
+// GOOD - Error appears at confirmPassword field
+z.object({
+  password: z.string(),
+  confirmPassword: z.string(),
+}).refine((data) => data.password === data.confirmPassword, {
+  message: "Passwords don't match",
+  path: ['confirmPassword'], // Specify path
+})
+```
+
+---
+
+## 11. Transform vs Preprocess Confusion
+
+**Error**: Data transformation doesn't work as expected
+
+**When to use each**:
+
+```typescript
+// Use TRANSFORM for output transformation (after validation)
+z.string().transform((val) => val.toUpperCase())
+// Input: 'hello' -> Validation: passes -> Output: 'HELLO'
+
+// Use PREPROCESS for input transformation (before validation)
+z.preprocess(
+  (val) => (val === '' ? undefined : val),
+  z.string().optional()
+)
+// Input: '' -> Preprocess: undefined -> Validation: passes
+```
+
+---
+
+## 12. Multiple Resolver Conflicts
+
+**Error**: Form validation doesn't work with multiple resolvers
+
+**Cause**: Trying to use multiple validation libraries simultaneously
+
+**Solution**:
+```typescript
+// BAD - Can't use multiple resolvers
+const form = useForm({
+  resolver: zodResolver(schema),
+  resolver: yupResolver(schema), // Overrides previous
+})
+
+// GOOD - Use single resolver, combine schemas if needed
+const schema1 = z.object({ email: z.string() })
+const schema2 = z.object({ password: z.string() })
+const combinedSchema = schema1.merge(schema2)
+
+const form = useForm({
+  resolver: zodResolver(combinedSchema),
+})
+```
+
+---
+
+## Debugging Tips
+
+### Enable DevTools
+
+```bash
+npm install @hookform/devtools
+```
+
+```typescript
+import { DevTool } from '@hookform/devtools'
+
+<DevTool control={control} />
+```
+
+### Log Form State
+
+```typescript
+useEffect(() => {
+  console.log('Form State:', formState)
+  console.log('Errors:', errors)
+  console.log('Values:', getValues())
+}, [formState, errors, getValues])
+```
+
+### Validate on Change During Development
+
+```typescript
+const form = useForm({
+  mode: 'onChange', // See errors immediately
+  resolver: zodResolver(schema),
+})
+```
+
+---
+
+**Official Docs**:
+- React Hook Form: https://react-hook-form.com/
+- Zod: https://zod.dev/

references/zod-schemas-guide.md

@@ -0,0 +1,396 @@
+# Comprehensive Zod Schemas Guide
+
+Complete reference for all Zod schema types and patterns.
+
+---
+
+## Primitives
+
+```typescript
+// String
+z.string()
+z.string().min(3, "Min 3 characters")
+z.string().max(100, "Max 100 characters")
+z.string().length(10, "Exactly 10 characters")
+z.string().email("Invalid email")
+z.string().url("Invalid URL")
+z.string().uuid("Invalid UUID")
+z.string().regex(/pattern/, "Does not match pattern")
+z.string().trim() // Trim whitespace
+z.string().toLowerCase() //Convert to lowercase
+z.string().toUpperCase() // Convert to uppercase
+
+// Number
+z.number()
+z.number().int("Must be integer")
+z.number().positive("Must be positive")
+z.number().negative("Must be negative")
+z.number().min(0, "Min is 0")
+z.number().max(100, "Max is 100")
+z.number().multipleOf(5, "Must be multiple of 5")
+z.number().finite() // No Infinity or NaN
+z.number().safe() // Within JS safe integer range
+
+// Boolean
+z.boolean()
+
+// Date
+z.date()
+z.date().min(new Date("2020-01-01"), "Too old")
+z.date().max(new Date(), "Cannot be in future")
+
+// BigInt
+z.bigint()
+```
+
+---
+
+## Objects
+
+```typescript
+// Basic object
+const userSchema = z.object({
+  name: z.string(),
+  age: z.number(),
+})
+
+// Nested object
+const profileSchema = z.object({
+  user: userSchema,
+  address: z.object({
+    street: z.string(),
+    city: z.string(),
+  }),
+})
+
+// Partial (all fields optional)
+const partialUserSchema = userSchema.partial()
+
+// Deep Partial (recursively optional)
+const deepPartialSchema = profileSchema.deepPartial()
+
+// Pick specific fields
+const nameOnlySchema = userSchema.pick({ name: true })
+
+// Omit specific fields
+const withoutAgeSchema = userSchema.omit({ age: true })
+
+// Merge objects
+const extendedUserSchema = userSchema.merge(z.object({
+  email: z.string().email(),
+}))
+
+// Passthrough (allow extra fields)
+const passthroughSchema = userSchema.passthrough()
+
+// Strict (no extra fields)
+const strictSchema = userSchema.strict()
+
+// Catchall (type for extra fields)
+const catchallSchema = userSchema.catchall(z.string())
+```
+
+---
+
+## Arrays
+
+```typescript
+// Array of strings
+z.array(z.string())
+
+// With length constraints
+z.array(z.string()).min(1, "At least one item required")
+z.array(z.string()).max(10, "Max 10 items")
+z.array(z.string()).length(5, "Exactly 5 items")
+z.array(z.string()).nonempty("Array cannot be empty")
+
+// Array of objects
+z.array(z.object({
+  name: z.string(),
+  age: z.number(),
+}))
+```
+
+---
+
+## Tuples
+
+```typescript
+// Fixed-length array with specific types
+z.tuple([z.string(), z.number(), z.boolean()])
+
+// With rest
+z.tuple([z.string(), z.number()]).rest(z.boolean())
+```
+
+---
+
+## Enums and Literals
+
+```typescript
+// Enum
+z.enum(['red', 'green', 'blue'])
+
+// Native enum
+enum Color { Red, Green, Blue }
+z.nativeEnum(Color)
+
+// Literal
+z.literal('hello')
+z.literal(42)
+z.literal(true)
+```
+
+---
+
+## Unions and Discriminated Unions
+
+```typescript
+// Union
+z.union([z.string(), z.number()])
+
+// Discriminated union (recommended for better errors)
+z.discriminatedUnion('type', [
+  z.object({ type: z.literal('user'), name: z.string() }),
+  z.object({ type: z.literal('admin'), permissions: z.array(z.string()) }),
+])
+```
+
+---
+
+## Optional and Nullable
+
+```typescript
+// Optional (value | undefined)
+z.string().optional()
+z.optional(z.string()) // Same as above
+
+// Nullable (value | null)
+z.string().nullable()
+z.nullable(z.string()) // Same as above
+
+// Nullish (value | null | undefined)
+z.string().nullish()
+```
+
+---
+
+## Default Values
+
+```typescript
+z.string().default('default value')
+z.number().default(0)
+z.boolean().default(false)
+z.array(z.string()).default([])
+```
+
+---
+
+## Refinements (Custom Validation)
+
+```typescript
+// Basic refinement
+z.string().refine((val) => val.length > 5, {
+  message: "String must be longer than 5 characters",
+})
+
+// With custom path
+z.object({
+  password: z.string(),
+  confirmPassword: z.string(),
+}).refine((data) => data.password === data.confirmPassword, {
+  message: "Passwords don't match",
+  path: ['confirmPassword'],
+})
+
+// Multiple refinements
+z.string()
+  .refine((val) => val.length >= 8, "Min 8 characters")
+  .refine((val) => /[A-Z]/.test(val), "Must contain uppercase")
+  .refine((val) => /[0-9]/.test(val), "Must contain number")
+
+// Async refinement
+z.string().refine(async (val) => {
+  const available = await checkAvailability(val)
+  return available
+}, "Already taken")
+```
+
+---
+
+## Transforms
+
+```typescript
+// String to number
+z.string().transform((val) => parseInt(val, 10))
+
+// Trim whitespace
+z.string().transform((val) => val.trim())
+
+// Parse date
+z.string().transform((val) => new Date(val))
+
+// Chain transform and refine
+z.string()
+  .transform((val) => parseInt(val, 10))
+  .refine((val) => !isNaN(val), "Must be a number")
+```
+
+---
+
+## Preprocess
+
+```typescript
+// Process before validation
+z.preprocess(
+  (val) => (val === '' ? undefined : val),
+  z.string().optional()
+)
+
+// Convert to number
+z.preprocess(
+  (val) => Number(val),
+  z.number()
+)
+```
+
+---
+
+## Intersections
+
+```typescript
+const baseUser = z.object({ name: z.string() })
+const withEmail = z.object({ email: z.string().email() })
+
+// Intersection (combines both)
+const userWithEmail = baseUser.and(withEmail)
+// OR
+const userWithEmail = z.intersection(baseUser, withEmail)
+```
+
+---
+
+## Records and Maps
+
+```typescript
+// Record (object with dynamic keys)
+z.record(z.string()) // { [key: string]: string }
+z.record(z.string(), z.number()) // { [key: string]: number }
+
+// Map
+z.map(z.string(), z.number())
+```
+
+---
+
+## Sets
+
+```typescript
+z.set(z.string())
+z.set(z.number()).min(1, "At least one item")
+z.set(z.string()).max(10, "Max 10 items")
+```
+
+---
+
+## Promises
+
+```typescript
+z.promise(z.string())
+z.promise(z.object({ data: z.string() }))
+```
+
+---
+
+## Custom Error Messages
+
+```typescript
+// Field-level
+z.string({ required_error: "Name is required" })
+z.number({ invalid_type_error: "Must be a number" })
+
+// Validation-level
+z.string().min(3, { message: "Min 3 characters" })
+z.string().email({ message: "Invalid email format" })
+
+// Custom error map
+const customErrorMap: z.ZodErrorMap = (issue, ctx) => {
+  if (issue.code === z.ZodIssueCode.invalid_type) {
+    if (issue.expected === "string") {
+      return { message: "Please enter text" }
+    }
+  }
+  return { message: ctx.defaultError }
+}
+
+z.setErrorMap(customErrorMap)
+```
+
+---
+
+## Type Inference
+
+```typescript
+const userSchema = z.object({
+  name: z.string(),
+  age: z.number(),
+})
+
+// Infer TypeScript type
+type User = z.infer<typeof userSchema>
+// Result: { name: string; age: number }
+
+// Input type (before transforms)
+type UserInput = z.input<typeof transformSchema>
+
+// Output type (after transforms)
+type UserOutput = z.output<typeof transformSchema>
+```
+
+---
+
+## Parsing Methods
+
+```typescript
+// .parse() - throws on error
+const result = schema.parse(data)
+
+// .safeParse() - returns result object
+const result = schema.safeParse(data)
+if (result.success) {
+  console.log(result.data)
+} else {
+  console.error(result.error)
+}
+
+// .parseAsync() - async validation
+const result = await schema.parseAsync(data)
+
+// .safeParseAsync() - async with result object
+const result = await schema.safeParseAsync(data)
+```
+
+---
+
+## Error Handling
+
+```typescript
+try {
+  schema.parse(data)
+} catch (error) {
+  if (error instanceof z.ZodError) {
+    // Formatted errors
+    console.log(error.format())
+
+    // Flattened errors (for forms)
+    console.log(error.flatten())
+
+    // Individual issues
+    console.log(error.issues)
+  }
+}
+```
+
+---
+
+**Official Docs**: https://zod.dev