diff --git a/README.md b/README.md
index acbbaa7..4d862ed 100644
--- a/README.md
+++ b/README.md
@@ -583,6 +583,76 @@ const serviceConfig = TemplateJson.gen(['obj', [
 ]]);
 ```
 
+## Helper Methods for Easy Generation
+
+The library provides convenient helper methods for generating common data types without needing to construct templates manually. These methods are available in the `examples` module:
+
+```typescript
+import { 
+  genUser, 
+  genAddress, 
+  genProduct, 
+  genOrder,
+  genRandomExample 
+} from '@jsonjoy.com/json-random/lib/examples';
+
+// Generate common data types quickly
+const user = genUser();
+const address = genAddress();
+const product = genProduct();
+const order = genOrder();
+
+// Generate random example from any template
+const randomData = genRandomExample();
+```
+
+### Available Helper Methods
+
+| Method | Description |
+|--------|-------------|
+| `genUser()` | Generate comprehensive user profile with details |
+| `genUserBasic()` | Generate basic user with essential information |
+| `genAddress()` | Generate address with street, city, state, etc. |
+| `genProduct()` | Generate product with name, price, category |
+| `genOrder()` | Generate order with items and customer info |
+| `genTransaction()` | Generate financial transaction data |
+| `genBankAccount()` | Generate bank account information |
+| `genSocialPost()` | Generate social media post |
+| `genSocialProfile()` | Generate social media profile |
+| `genLocation()` | Generate location with coordinates |
+| `genApiResponse()` | Generate API response with data array |
+| `genApiResponseDetailed()` | Generate comprehensive API response |
+| `genServiceConfig()` | Generate service configuration |
+| `genPatient()` | Generate medical patient record |
+| `genMedicalRecord()` | Generate comprehensive medical record |
+| `genStudent()` | Generate student profile |
+| `genCourse()` | Generate course information |
+| `genSensorReading()` | Generate IoT sensor reading |
+| `genIotDevice()` | Generate IoT device profile |
+| `genLogEntry()` | Generate log entry for monitoring |
+| `genMetricData()` | Generate metric data for monitoring |
+| `genRandomExample()` | Generate random data from any available template |
+
+### Usage Examples
+
+```typescript
+// Generate test user data for API testing
+const testUser = genUser();
+console.log(testUser);
+// Output: { id: 4829, username: "user_7432", email: "alice@gmail.com", ... }
+
+// Generate address for form testing
+const shippingAddress = genAddress();
+console.log(shippingAddress);
+// Output: { street: "123 Main St", city: "Springfield", state: "CA", ... }
+
+// Generate product catalog
+const products = Array.from({ length: 10 }, () => genProduct());
+
+// Generate random test data
+const randomTestData = Array.from({ length: 5 }, () => genRandomExample());
+```
+
 ## Demos
 
 Run the included demos to see the library in action:
diff --git a/src/__demos__/templates-demo.ts b/src/__demos__/templates-demo.ts
new file mode 100644
index 0000000..1ca633c
--- /dev/null
+++ b/src/__demos__/templates-demo.ts
@@ -0,0 +1,71 @@
+import {TemplateJson} from '../structured/TemplateJson';
+import * as templates from '../examples';
+
+console.log('🎲 JSON Random Template Examples\n');
+
+console.log('📧 Email addresses:');
+for (let i = 0; i < 3; i++) {
+  const email = TemplateJson.gen(['str', templates.tokenEmail]);
+  console.log(`  ${email}`);
+}
+
+console.log('\n📞 Phone numbers:');
+for (let i = 0; i < 3; i++) {
+  const phone = TemplateJson.gen(['str', templates.tokenPhone]);
+  console.log(`  ${phone}`);
+}
+
+console.log('\n🏷️ Product codes:');
+for (let i = 0; i < 3; i++) {
+  const code = TemplateJson.gen(['str', templates.tokenProductCode]);
+  console.log(`  ${code}`);
+}
+
+console.log('\n👤 User profile:');
+const user = TemplateJson.gen(templates.userProfile);
+console.log(JSON.stringify(user, null, 2));
+
+console.log('\n🛒 E-commerce product:');
+const product = TemplateJson.gen(templates.product);
+console.log(JSON.stringify(product, null, 2));
+
+console.log('\n📋 Order:');
+const order = TemplateJson.gen(templates.order);
+console.log(JSON.stringify(order, null, 2));
+
+console.log('\n🌐 API Response:');
+const apiResponse = TemplateJson.gen(templates.apiResponse);
+console.log(JSON.stringify(apiResponse, null, 2));
+
+console.log('\n🏥 Patient record:');
+const patient = TemplateJson.gen(templates.patient);
+console.log(JSON.stringify(patient, null, 2));
+
+console.log('\n📊 IoT Sensor reading:');
+const sensor = TemplateJson.gen(templates.sensorReading);
+console.log(JSON.stringify(sensor, null, 2));
+
+console.log('\n🌳 Tree structure (recursive):');
+const tree = TemplateJson.gen(templates.tree());
+console.log(JSON.stringify(tree, null, 2));
+
+console.log('\n🔀 Mixed types (or template):');
+for (let i = 0; i < 5; i++) {
+  const mixed = TemplateJson.gen(templates.mixedTypes);
+  console.log(`  ${typeof mixed}: ${JSON.stringify(mixed)}`);
+}
+
+console.log('\n🎯 Edge cases:');
+const empty = TemplateJson.gen(templates.emptyStructures);
+console.log(JSON.stringify(empty, null, 2));
+
+console.log('\n📏 Large numbers:');
+const large = TemplateJson.gen(templates.largeNumbers);
+console.log(JSON.stringify(large, null, 2));
+
+console.log('\n🎰 Random examples from allExamples template:');
+for (let i = 0; i < 3; i++) {
+  const example = TemplateJson.gen(templates.allExamples);
+  console.log(`Example ${i + 1}:`, JSON.stringify(example, null, 2));
+  console.log('---');
+}
diff --git a/src/examples.ts b/src/examples.ts
new file mode 100644
index 0000000..5bb21fe
--- /dev/null
+++ b/src/examples.ts
@@ -0,0 +1,1231 @@
+import type {Token} from './string';
+import type {StringTemplate, Template, ObjectTemplate, ArrayTemplate, MapTemplate} from './structured/types';
+import {TemplateJson} from './structured/TemplateJson';
+
+// ============================================================================
+// String Pattern Templates (from README examples)
+// ============================================================================
+
+export const tokenEmail: Token = [
+  'list',
+  ['repeat', 3, 12, ['char', 97, 122]], // 3-12 lowercase letters
+  ['pick', '.', '_', '-', ''], // Optional separator
+  ['repeat', 0, 5, ['char', 97, 122]], // 0-5 more letters
+  '@',
+  ['pick', 'gmail.com', 'yahoo.com', 'example.org', 'test.com', 'demo.net'],
+];
+
+export const tokenPhone: Token = [
+  'list',
+  '+1-',
+  ['char', 50, 57, 3], // Area code (2-9)
+  '-',
+  ['char', 48, 57, 3], // Exchange
+  '-',
+  ['char', 48, 57, 4], // Number
+];
+
+export const tokenProductCode: Token = [
+  'list',
+  ['pick', 'PRD', 'ITM', 'SKU'],
+  '-',
+  ['char', 65, 90, 2], // 2 uppercase letters
+  ['char', 48, 57, 6], // 6 digits
+];
+
+export const tokenUrl: Token = [
+  'list',
+  'https://',
+  ['repeat', 3, 15, ['char', 97, 122]], // Domain name
+  ['pick', '.com', '.org', '.net', '.io'],
+  ['pick', '', '/', '/api/', '/v1/'],
+  ['repeat', 0, 10, ['char', 97, 122]], // Optional path
+];
+
+export const tokenUsername: Token = [
+  'list',
+  ['pick', 'user', 'admin', 'guest', 'test'],
+  ['char', 48, 57, 4], // 4 digits
+];
+
+// ============================================================================
+// User Profile Templates (from README examples)
+// ============================================================================
+
+export const userProfile: ObjectTemplate = [
+  'obj',
+  [
+    ['id', ['int', 1, 10000]],
+    ['username', ['str', tokenUsername]],
+    ['email', ['str', tokenEmail]],
+    ['age', ['int', 18, 120]],
+    ['isActive', 'bool'],
+    [
+      'profile',
+      [
+        'obj',
+        [
+          ['bio', ['str', ['repeat', 10, 50, ['char', 32, 126]]]],
+          ['avatar', ['str', ['list', 'https://avatar.example.com/', ['char', 48, 57, 8]]], 0.3], // 30% chance to omit
+        ],
+      ],
+    ],
+  ],
+];
+
+export const userBasic: ObjectTemplate = [
+  'obj',
+  [
+    ['id', ['int', 1, 1000]],
+    [
+      'name',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'John', 'Jane', 'Bob', 'Alice', 'Charlie'],
+          ' ',
+          ['pick', 'Doe', 'Smith', 'Johnson', 'Brown'],
+        ],
+      ],
+    ],
+    ['active', 'bool'],
+  ],
+];
+
+// ============================================================================
+// API Response Templates (from README examples)
+// ============================================================================
+
+export const apiResponse: ObjectTemplate = [
+  'obj',
+  [
+    ['status', ['str', ['pick', 'success', 'error']]],
+    ['timestamp', ['int', 1640000000, 1700000000]],
+    [
+      'data',
+      [
+        'arr',
+        0,
+        10,
+        [
+          'obj',
+          [
+            ['id', 'int'],
+            ['value', 'str'],
+          ],
+        ],
+      ],
+    ],
+  ],
+];
+
+export const apiResponseDetailed: ObjectTemplate = [
+  'obj',
+  [
+    ['success', ['lit', true]],
+    ['timestamp', ['lit', Date.now()]],
+    [
+      'data',
+      [
+        'arr',
+        5,
+        15,
+        [
+          'obj',
+          [
+            ['id', 'int'],
+            ['status', ['str', ['pick', 'pending', 'completed', 'failed']]],
+            ['value', ['float', 0, 1000]],
+          ],
+        ],
+      ],
+    ],
+  ],
+];
+
+// ============================================================================
+// Configuration Templates (from README examples)
+// ============================================================================
+
+export const serviceConfig: ObjectTemplate = [
+  'obj',
+  [
+    [
+      'database',
+      [
+        'obj',
+        [
+          ['host', ['str', ['list', 'db-', ['char', 48, 57, 2], '.example.com']]],
+          ['port', ['int', 3000, 6000]],
+          ['timeout', ['int', 1000, 30000]],
+          ['pool_size', ['int', 5, 50]],
+        ],
+      ],
+    ],
+    [
+      'cache',
+      [
+        'obj',
+        [
+          ['enabled', 'bool'],
+          ['ttl', ['int', 60, 3600]],
+          ['max_size', ['int', 100, 10000]],
+        ],
+      ],
+    ],
+    ['features', ['map', ['pick', 'feature_a', 'feature_b', 'feature_c', 'feature_d'], 'bool', 2, 5]],
+  ],
+];
+
+export const configMap: MapTemplate = [
+  'map',
+  ['pick', 'timeout', 'retries', 'cache_ttl', 'max_connections'],
+  ['int', 1, 3600],
+  3,
+  5,
+];
+
+export const permissions: MapTemplate = [
+  'map',
+  ['list', 'can_', ['pick', 'read', 'write', 'delete', 'admin']],
+  'bool',
+  2,
+  6,
+];
+
+export const translations: MapTemplate = [
+  'map',
+  ['pick', 'welcome', 'goodbye', 'error', 'success', 'loading'],
+  ['str', ['repeat', 5, 20, ['char', 32, 126]]],
+  3,
+  8,
+];
+
+// ============================================================================
+// Recursive Templates (from README examples)
+// ============================================================================
+
+export const tree = (): Template => [
+  'obj',
+  [
+    ['value', 'int'],
+    ['left', tree, 0.3], // 30% chance of left child
+    ['right', tree, 0.3], // 30% chance of right child
+  ],
+];
+
+export const comment = (): Template => [
+  'obj',
+  [
+    ['id', 'int'],
+    ['text', 'str'],
+    ['author', 'str'],
+    ['replies', ['arr', 0, 3, comment, [], []], 0.4], // 40% chance of replies
+  ],
+];
+
+// ============================================================================
+// E-commerce Templates
+// ============================================================================
+
+export const product: ObjectTemplate = [
+  'obj',
+  [
+    ['id', ['str', ['list', 'prod_', ['char', 48, 57, 8]]]],
+    [
+      'name',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'Premium', 'Deluxe', 'Classic', 'Modern', 'Vintage'],
+          ' ',
+          ['pick', 'Widget', 'Gadget', 'Tool', 'Device', 'Accessory'],
+        ],
+      ],
+    ],
+    ['price', ['float', 9.99, 999.99]],
+    ['currency', ['str', ['pick', 'USD', 'EUR', 'GBP', 'JPY']]],
+    ['category', ['str', ['pick', 'electronics', 'clothing', 'books', 'home', 'sports']]],
+    ['tags', ['arr', 1, 5, ['str', ['pick', 'new', 'sale', 'featured', 'popular', 'limited']]]],
+    [
+      'inventory',
+      [
+        'obj',
+        [
+          ['stock', ['int', 0, 1000]],
+          ['warehouse', ['str', ['list', 'WH-', ['char', 65, 90, 2], ['char', 48, 57, 3]]]],
+          ['reserved', ['int', 0, 50]],
+        ],
+      ],
+    ],
+    ['rating', ['float', 1.0, 5.0]],
+    ['reviews', ['int', 0, 10000]],
+  ],
+];
+
+export const order: ObjectTemplate = [
+  'obj',
+  [
+    ['orderId', ['str', ['list', 'ORD-', ['char', 48, 57, 10]]]],
+    ['customerId', ['str', ['list', 'CUST-', ['char', 65, 90, 3], ['char', 48, 57, 6]]]],
+    [
+      'items',
+      [
+        'arr',
+        1,
+        8,
+        [
+          'obj',
+          [
+            ['productId', ['str', tokenProductCode]],
+            ['quantity', ['int', 1, 10]],
+            ['price', ['float', 5.0, 500.0]],
+          ],
+        ],
+      ],
+    ],
+    ['total', ['float', 10.0, 2000.0]],
+    ['status', ['str', ['pick', 'pending', 'processing', 'shipped', 'delivered', 'cancelled']]],
+    ['createdAt', ['int', 1640000000, 1700000000]],
+    [
+      'shippingAddress',
+      [
+        'obj',
+        [
+          [
+            'street',
+            ['str', ['list', ['char', 48, 57, 3], ' ', ['pick', 'Main St', 'Oak Ave', 'Pine Rd', 'Cedar Ln']]],
+          ],
+          ['city', ['str', ['pick', 'New York', 'Los Angeles', 'Chicago', 'Houston', 'Phoenix']]],
+          ['state', ['str', ['pick', 'NY', 'CA', 'IL', 'TX', 'AZ']]],
+          ['zipCode', ['str', ['char', 48, 57, 5]]],
+          ['country', ['str', ['pick', 'US', 'CA', 'MX']]],
+        ],
+      ],
+    ],
+  ],
+];
+
+// ============================================================================
+// Authentication & Security Templates
+// ============================================================================
+
+export const userToken: ObjectTemplate = [
+  'obj',
+  [
+    ['token', ['str', ['list', 'eyJ', ['repeat', 20, 40, ['char', 65, 90]]]]],
+    ['refreshToken', ['str', ['list', 'rt_', ['repeat', 32, 64, ['char', 97, 122]]]]],
+    ['expiresAt', ['int', Date.now(), Date.now() + 86400000]],
+    ['scope', ['arr', 1, 4, ['str', ['pick', 'read', 'write', 'admin', 'user']]]],
+  ],
+];
+
+export const userRole: ObjectTemplate = [
+  'obj',
+  [
+    ['roleId', ['str', ['list', 'role_', ['char', 48, 57, 6]]]],
+    ['name', ['str', ['pick', 'admin', 'user', 'moderator', 'guest', 'super_admin']]],
+    [
+      'permissions',
+      [
+        'arr',
+        2,
+        10,
+        [
+          'str',
+          [
+            'pick',
+            'users:read',
+            'users:write',
+            'users:delete',
+            'posts:read',
+            'posts:write',
+            'posts:delete',
+            'admin:read',
+            'admin:write',
+            'system:manage',
+          ],
+        ],
+      ],
+    ],
+    ['createdBy', ['str', tokenUsername]],
+    ['isActive', 'bool'],
+  ],
+];
+
+// ============================================================================
+// Logging & Monitoring Templates
+// ============================================================================
+
+export const logEntry: ObjectTemplate = [
+  'obj',
+  [
+    ['timestamp', ['int', Date.now() - 86400000, Date.now()]],
+    ['level', ['str', ['pick', 'debug', 'info', 'warn', 'error', 'fatal']]],
+    [
+      'message',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'User', 'System', 'Database', 'API', 'Cache'],
+          ' ',
+          ['pick', 'action', 'error', 'warning', 'success', 'failure'],
+          ': ',
+          ['repeat', 10, 50, ['char', 32, 126]],
+        ],
+      ],
+    ],
+    ['service', ['str', ['pick', 'web-server', 'database', 'cache', 'auth-service', 'api-gateway']]],
+    ['userId', ['str', tokenUsername], 0.7],
+    ['requestId', ['str', ['list', 'req_', ['char', 97, 122, 8], ['char', 48, 57, 4]]]],
+    [
+      'metadata',
+      [
+        'obj',
+        [
+          [
+            'ip',
+            [
+              'str',
+              [
+                'list',
+                ['char', 49, 57],
+                ['char', 48, 57, 2],
+                '.',
+                ['char', 48, 57, 3],
+                '.',
+                ['char', 48, 57, 3],
+                '.',
+                ['char', 48, 57, 3],
+              ],
+            ],
+          ],
+          [
+            'userAgent',
+            [
+              'str',
+              [
+                'pick',
+                'Mozilla/5.0 (Windows NT 10.0; Win64; x64)',
+                'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7)',
+                'Mozilla/5.0 (X11; Linux x86_64)',
+              ],
+            ],
+          ],
+          ['duration', ['int', 1, 5000]],
+        ],
+      ],
+      0.5,
+    ],
+  ],
+];
+
+export const metricData: ObjectTemplate = [
+  'obj',
+  [
+    ['name', ['str', ['pick', 'cpu_usage', 'memory_usage', 'disk_io', 'network_latency', 'request_count']]],
+    ['value', ['float', 0, 100]],
+    ['unit', ['str', ['pick', 'percent', 'bytes', 'ms', 'count', 'rate']]],
+    ['timestamp', ['int', Date.now() - 3600000, Date.now()]],
+    [
+      'tags',
+      [
+        'obj',
+        [
+          ['environment', ['str', ['pick', 'production', 'staging', 'development']]],
+          ['service', ['str', ['pick', 'web', 'api', 'database', 'cache']]],
+          ['region', ['str', ['pick', 'us-east-1', 'us-west-2', 'eu-west-1']]],
+        ],
+      ],
+    ],
+  ],
+];
+
+// ============================================================================
+// Geographic & Location Templates
+// ============================================================================
+
+export const coordinates: ArrayTemplate = [
+  'arr',
+  0,
+  0,
+  'nil',
+  [
+    ['float', -180, 180],
+    ['float', -90, 90],
+  ], // head: [longitude, latitude]
+  [['lit', 'WGS84']], // tail: coordinate system
+];
+
+export const address: ObjectTemplate = [
+  'obj',
+  [
+    [
+      'street',
+      ['str', ['list', ['char', 48, 57, 3], ' ', ['pick', 'Main St', 'Oak Ave', 'Pine Rd', 'Elm St', 'Maple Dr']]],
+    ],
+    [
+      'city',
+      ['str', ['pick', 'New York', 'Los Angeles', 'Chicago', 'Houston', 'Phoenix', 'Philadelphia', 'San Antonio']],
+    ],
+    ['state', ['str', ['pick', 'NY', 'CA', 'IL', 'TX', 'AZ', 'PA']]],
+    ['country', ['str', ['pick', 'United States', 'Canada', 'Mexico', 'United Kingdom', 'Germany', 'France']]],
+    ['postalCode', ['str', ['char', 48, 57, 5]]],
+    ['coordinates', coordinates, 0.3],
+  ],
+];
+
+export const location: ObjectTemplate = [
+  'obj',
+  [
+    [
+      'name',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'Coffee Shop', 'Restaurant', 'Store', 'Office', 'Park'],
+          ' ',
+          ['pick', 'Downtown', 'Central', 'North', 'South', 'Main'],
+        ],
+      ],
+    ],
+    ['address', address],
+    ['phone', ['str', tokenPhone]],
+    [
+      'hours',
+      [
+        'obj',
+        [
+          ['monday', ['str', ['pick', '9:00-17:00', '8:00-18:00', 'closed']]],
+          ['tuesday', ['str', ['pick', '9:00-17:00', '8:00-18:00', 'closed']]],
+          ['wednesday', ['str', ['pick', '9:00-17:00', '8:00-18:00', 'closed']]],
+          ['thursday', ['str', ['pick', '9:00-17:00', '8:00-18:00', 'closed']]],
+          ['friday', ['str', ['pick', '9:00-17:00', '8:00-18:00', 'closed']]],
+          ['saturday', ['str', ['pick', '10:00-16:00', '9:00-15:00', 'closed']]],
+          ['sunday', ['str', ['pick', '12:00-16:00', 'closed']]],
+        ],
+      ],
+      0.4,
+    ],
+  ],
+];
+
+// ============================================================================
+// Financial & Transaction Templates
+// ============================================================================
+
+export const transaction: ObjectTemplate = [
+  'obj',
+  [
+    ['id', ['str', ['list', 'txn_', ['char', 97, 122, 8], ['char', 48, 57, 8]]]],
+    ['amount', ['float', 0.01, 10000.0]],
+    ['currency', ['str', ['pick', 'USD', 'EUR', 'GBP', 'JPY', 'CAD', 'AUD']]],
+    ['type', ['str', ['pick', 'debit', 'credit', 'transfer', 'payment', 'refund']]],
+    ['status', ['str', ['pick', 'pending', 'completed', 'failed', 'cancelled']]],
+    ['fromAccount', ['str', ['list', 'acc_', ['char', 48, 57, 12]]]],
+    ['toAccount', ['str', ['list', 'acc_', ['char', 48, 57, 12]]]],
+    [
+      'description',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'Payment to', 'Transfer from', 'Purchase at', 'Refund for'],
+          ' ',
+          ['repeat', 5, 20, ['char', 32, 126]],
+        ],
+      ],
+    ],
+    ['timestamp', ['int', Date.now() - 86400000, Date.now()]],
+    ['fees', ['float', 0, 50.0], 0.3],
+  ],
+];
+
+export const bankAccount: ObjectTemplate = [
+  'obj',
+  [
+    ['accountNumber', ['str', ['char', 48, 57, 12]]],
+    ['routingNumber', ['str', ['char', 48, 57, 9]]],
+    ['accountType', ['str', ['pick', 'checking', 'savings', 'business', 'credit']]],
+    ['balance', ['float', 0, 100000.0]],
+    ['currency', ['str', ['pick', 'USD', 'EUR', 'GBP']]],
+    ['isActive', 'bool'],
+    ['openedDate', ['int', 946684800, Date.now()]], // From year 2000
+    ['lastActivity', ['int', Date.now() - 2592000, Date.now()]], // Last 30 days
+  ],
+];
+
+// ============================================================================
+// Social Media Templates
+// ============================================================================
+
+export const socialPost: ObjectTemplate = [
+  'obj',
+  [
+    ['id', ['str', ['list', 'post_', ['char', 97, 122, 8]]]],
+    ['content', ['str', ['repeat', 10, 280, ['char', 32, 126]]]],
+    [
+      'author',
+      [
+        'obj',
+        [
+          ['username', ['str', tokenUsername]],
+          [
+            'displayName',
+            [
+              'str',
+              [
+                'list',
+                ['pick', 'John', 'Jane', 'Alex', 'Sam', 'Chris'],
+                ' ',
+                ['pick', 'Smith', 'Doe', 'Johnson', 'Brown'],
+              ],
+            ],
+          ],
+          ['verified', 'bool'],
+        ],
+      ],
+    ],
+    ['likes', ['int', 0, 10000]],
+    ['shares', ['int', 0, 1000]],
+    ['comments', ['int', 0, 500]],
+    ['hashtags', ['arr', 0, 5, ['str', ['list', '#', ['repeat', 3, 15, ['char', 97, 122]]]]]],
+    ['mentions', ['arr', 0, 3, ['str', ['list', '@', tokenUsername]]]],
+    ['timestamp', ['int', Date.now() - 604800000, Date.now()]], // Last week
+    [
+      'media',
+      [
+        'arr',
+        0,
+        4,
+        [
+          'obj',
+          [
+            ['type', ['str', ['pick', 'image', 'video', 'gif']]],
+            ['url', ['str', tokenUrl]],
+            ['alt', ['str', ['repeat', 5, 50, ['char', 32, 126]]], 0.7],
+          ],
+        ],
+      ],
+      0.4,
+    ],
+  ],
+];
+
+export const socialProfile: ObjectTemplate = [
+  'obj',
+  [
+    ['username', ['str', tokenUsername]],
+    ['displayName', ['str', ['repeat', 3, 30, ['char', 32, 126]]]],
+    ['bio', ['str', ['repeat', 10, 160, ['char', 32, 126]]], 0.8],
+    ['followers', ['int', 0, 1000000]],
+    ['following', ['int', 0, 10000]],
+    ['posts', ['int', 0, 50000]],
+    ['verified', 'bool'],
+    ['joinDate', ['int', 946684800, Date.now()]],
+    ['location', ['str', ['pick', 'New York', 'London', 'Tokyo', 'Berlin', 'Sydney']], 0.6],
+    ['website', ['str', tokenUrl], 0.3],
+  ],
+];
+
+// ============================================================================
+// IoT & Sensor Data Templates
+// ============================================================================
+
+export const sensorReading: ObjectTemplate = [
+  'obj',
+  [
+    ['sensorId', ['str', ['list', 'sensor_', ['char', 65, 90, 2], ['char', 48, 57, 6]]]],
+    ['deviceType', ['str', ['pick', 'temperature', 'humidity', 'pressure', 'motion', 'light', 'sound']]],
+    ['value', ['float', -50, 150]],
+    ['unit', ['str', ['pick', 'celsius', 'fahrenheit', 'percent', 'pascal', 'lux', 'decibel']]],
+    ['timestamp', ['int', Date.now() - 3600000, Date.now()]],
+    [
+      'location',
+      [
+        'obj',
+        [
+          ['room', ['str', ['pick', 'living_room', 'bedroom', 'kitchen', 'bathroom', 'office']]],
+          ['floor', ['int', 1, 10]],
+          ['building', ['str', ['list', 'Building ', ['char', 65, 90]]]],
+        ],
+      ],
+    ],
+    ['status', ['str', ['pick', 'online', 'offline', 'maintenance', 'error']]],
+    ['battery', ['int', 0, 100], 0.6],
+  ],
+];
+
+export const iotDevice: ObjectTemplate = [
+  'obj',
+  [
+    ['deviceId', ['str', ['list', 'iot_', ['char', 97, 122, 4], ['char', 48, 57, 8]]]],
+    [
+      'name',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'Smart', 'Connected', 'Wireless', 'Digital'],
+          ' ',
+          ['pick', 'Thermostat', 'Camera', 'Lock', 'Light', 'Sensor'],
+        ],
+      ],
+    ],
+    ['manufacturer', ['str', ['pick', 'SmartHome Inc', 'IoT Solutions', 'TechDevice Co', 'ConnectCorp']]],
+    ['model', ['str', ['list', ['char', 65, 90, 2], '-', ['char', 48, 57, 4]]]],
+    ['firmwareVersion', ['str', ['list', ['char', 49, 57], '.', ['char', 48, 57], '.', ['char', 48, 57]]]],
+    ['ipAddress', ['str', ['list', '192.168.', ['char', 48, 57, 1], '.', ['char', 48, 57, 3]]]],
+    [
+      'macAddress',
+      [
+        'str',
+        [
+          'list',
+          ['char', 48, 57, 2],
+          ':',
+          ['char', 48, 57, 2],
+          ':',
+          ['char', 48, 57, 2],
+          ':',
+          ['char', 48, 57, 2],
+          ':',
+          ['char', 48, 57, 2],
+          ':',
+          ['char', 48, 57, 2],
+        ],
+      ],
+    ],
+    ['lastSeen', ['int', Date.now() - 86400000, Date.now()]],
+    ['sensors', ['arr', 1, 4, sensorReading]],
+  ],
+];
+
+// ============================================================================
+// Medical Records Templates
+// ============================================================================
+
+export const patient: ObjectTemplate = [
+  'obj',
+  [
+    ['patientId', ['str', ['list', 'PAT-', ['char', 48, 57, 8]]]],
+    ['firstName', ['str', ['pick', 'John', 'Jane', 'Michael', 'Sarah', 'David', 'Emily', 'James', 'Lisa']]],
+    ['lastName', ['str', ['pick', 'Smith', 'Johnson', 'Williams', 'Brown', 'Jones', 'Garcia', 'Miller', 'Davis']]],
+    ['dateOfBirth', ['int', 157766400, 1009843200]], // 1975-2002
+    ['gender', ['str', ['pick', 'male', 'female', 'non-binary', 'prefer-not-to-say']]],
+    ['bloodType', ['str', ['pick', 'A+', 'A-', 'B+', 'B-', 'AB+', 'AB-', 'O+', 'O-']]],
+    ['allergies', ['arr', 0, 5, ['str', ['pick', 'peanuts', 'shellfish', 'dairy', 'gluten', 'penicillin', 'latex']]]],
+    [
+      'emergencyContact',
+      [
+        'obj',
+        [
+          [
+            'name',
+            [
+              'str',
+              [
+                'list',
+                ['pick', 'John', 'Jane', 'Michael', 'Sarah'],
+                ' ',
+                ['pick', 'Smith', 'Johnson', 'Williams', 'Brown'],
+              ],
+            ],
+          ],
+          ['relationship', ['str', ['pick', 'spouse', 'parent', 'sibling', 'child', 'friend']]],
+          ['phone', ['str', tokenPhone]],
+        ],
+      ],
+    ],
+    [
+      'insurance',
+      [
+        'obj',
+        [
+          ['provider', ['str', ['pick', 'HealthCare Plus', 'MedInsure', 'WellnessCare', 'LifeHealth']]],
+          ['policyNumber', ['str', ['list', ['char', 65, 90, 3], ['char', 48, 57, 9]]]],
+          ['groupNumber', ['str', ['char', 48, 57, 6]]],
+        ],
+      ],
+      0.9,
+    ],
+  ],
+];
+
+export const medicalRecord: ObjectTemplate = [
+  'obj',
+  [
+    ['recordId', ['str', ['list', 'MED-', ['char', 48, 57, 10]]]],
+    ['patientId', ['str', ['list', 'PAT-', ['char', 48, 57, 8]]]],
+    ['visitDate', ['int', Date.now() - 31536000, Date.now()]], // Last year
+    [
+      'provider',
+      [
+        'obj',
+        [
+          [
+            'name',
+            [
+              'str',
+              [
+                'list',
+                'Dr. ',
+                ['pick', 'John', 'Jane', 'Michael', 'Sarah'],
+                ' ',
+                ['pick', 'Smith', 'Johnson', 'Williams'],
+              ],
+            ],
+          ],
+          ['specialty', ['str', ['pick', 'cardiology', 'neurology', 'pediatrics', 'orthopedics', 'dermatology']]],
+          ['license', ['str', ['list', ['char', 65, 90, 2], ['char', 48, 57, 8]]]],
+        ],
+      ],
+    ],
+    ['diagnosis', ['arr', 1, 3, ['str', ['pick', 'hypertension', 'diabetes', 'asthma', 'arthritis', 'migraine']]]],
+    [
+      'medications',
+      [
+        'arr',
+        0,
+        5,
+        [
+          'obj',
+          [
+            ['name', ['str', ['pick', 'Lisinopril', 'Metformin', 'Albuterol', 'Ibuprofen', 'Atorvastatin']]],
+            ['dosage', ['str', ['list', ['char', 48, 57, 2], 'mg']]],
+            ['frequency', ['str', ['pick', 'once daily', 'twice daily', 'three times daily', 'as needed']]],
+          ],
+        ],
+      ],
+    ],
+    [
+      'vitals',
+      [
+        'obj',
+        [
+          ['bloodPressure', ['str', ['list', ['char', 49, 57], ['char', 48, 57, 2], '/', ['char', 48, 57, 2]]]],
+          ['heartRate', ['int', 60, 100]],
+          ['temperature', ['float', 96.0, 104.0]],
+          ['weight', ['float', 100, 300]],
+        ],
+      ],
+      0.8,
+    ],
+  ],
+];
+
+// ============================================================================
+// Educational Data Templates
+// ============================================================================
+
+export const student: ObjectTemplate = [
+  'obj',
+  [
+    ['studentId', ['str', ['list', 'STU-', ['char', 48, 57, 7]]]],
+    ['firstName', ['str', ['pick', 'Alex', 'Sam', 'Jordan', 'Casey', 'Taylor', 'Morgan', 'Riley', 'Avery']]],
+    ['lastName', ['str', ['pick', 'Anderson', 'Brown', 'Clark', 'Davis', 'Evans', 'Foster', 'Green', 'Hill']]],
+    ['email', ['str', tokenEmail]],
+    ['grade', ['str', ['pick', '9th', '10th', '11th', '12th', 'Freshman', 'Sophomore', 'Junior', 'Senior']]],
+    [
+      'major',
+      ['str', ['pick', 'Computer Science', 'Biology', 'Mathematics', 'English', 'History', 'Physics', 'Chemistry']],
+      0.7,
+    ],
+    ['gpa', ['float', 2.0, 4.0]],
+    ['enrollmentDate', ['int', 1567296000, Date.now()]], // From 2019
+  ],
+];
+
+export const course: ObjectTemplate = [
+  'obj',
+  [
+    ['courseId', ['str', ['list', ['char', 65, 90, 3], '-', ['char', 48, 57, 3]]]],
+    [
+      'title',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'Introduction to', 'Advanced', 'Fundamentals of', 'Applied'],
+          ' ',
+          ['pick', 'Computer Science', 'Mathematics', 'Biology', 'Chemistry', 'Physics', 'History', 'Literature'],
+        ],
+      ],
+    ],
+    ['credits', ['int', 1, 6]],
+    [
+      'instructor',
+      [
+        'obj',
+        [
+          [
+            'name',
+            [
+              'str',
+              [
+                'list',
+                'Prof. ',
+                ['pick', 'John', 'Jane', 'Michael', 'Sarah'],
+                ' ',
+                ['pick', 'Smith', 'Johnson', 'Williams'],
+              ],
+            ],
+          ],
+          ['email', ['str', tokenEmail]],
+          ['office', ['str', ['list', ['char', 65, 90], '-', ['char', 48, 57, 3]]]],
+        ],
+      ],
+    ],
+    [
+      'schedule',
+      [
+        'obj',
+        [
+          ['days', ['arr', 1, 3, ['str', ['pick', 'Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday']]]],
+          [
+            'time',
+            [
+              'str',
+              [
+                'list',
+                ['char', 48, 57, 2],
+                ':',
+                ['pick', '00', '30'],
+                '-',
+                ['char', 48, 57, 2],
+                ':',
+                ['pick', '00', '30'],
+              ],
+            ],
+          ],
+          ['room', ['str', ['list', ['char', 65, 90], '-', ['char', 48, 57, 3]]]],
+        ],
+      ],
+    ],
+    ['capacity', ['int', 15, 200]],
+    ['enrolled', ['int', 5, 180]],
+  ],
+];
+
+export const grade: ObjectTemplate = [
+  'obj',
+  [
+    ['studentId', ['str', ['list', 'STU-', ['char', 48, 57, 7]]]],
+    ['courseId', ['str', ['list', ['char', 65, 90, 3], '-', ['char', 48, 57, 3]]]],
+    ['semester', ['str', ['pick', 'Fall 2023', 'Spring 2024', 'Summer 2024', 'Fall 2024']]],
+    [
+      'assignments',
+      [
+        'arr',
+        3,
+        8,
+        [
+          'obj',
+          [
+            [
+              'name',
+              ['str', ['list', ['pick', 'Assignment', 'Quiz', 'Exam', 'Project', 'Lab'], ' ', ['char', 48, 57, 1]]],
+            ],
+            ['score', ['float', 0, 100]],
+            ['maxScore', ['lit', 100]],
+            ['dueDate', ['int', Date.now() - 7776000, Date.now() + 7776000]], // +/- 90 days
+            ['submitted', 'bool'],
+          ],
+        ],
+      ],
+    ],
+    ['finalGrade', ['str', ['pick', 'A+', 'A', 'A-', 'B+', 'B', 'B-', 'C+', 'C', 'C-', 'D+', 'D', 'F']]],
+    ['gpa', ['float', 0.0, 4.0]],
+  ],
+];
+
+// ============================================================================
+// Edge Cases & Special Templates
+// ============================================================================
+
+export const emptyStructures: ObjectTemplate = [
+  'obj',
+  [
+    ['emptyObject', ['obj', []]],
+    ['emptyArray', ['arr', 0, 0]],
+    ['emptyString', ['lit', '']],
+    ['nullValue', 'nil'],
+    ['zeroNumber', ['lit', 0]],
+    ['falseBool', ['lit', false]],
+  ],
+];
+
+export const unicodeText: ObjectTemplate = [
+  'obj',
+  [
+    ['ascii', ['str', ['repeat', 5, 15, ['char', 32, 126]]]],
+    ['latin', ['str', ['repeat', 5, 15, ['char', 160, 255]]]],
+    ['emoji', ['str', ['repeat', 1, 5, ['char', 0x1f600, 0x1f64f]]]],
+    ['chinese', ['str', ['repeat', 3, 8, ['char', 0x4e00, 0x9fff]]]],
+    ['arabic', ['str', ['repeat', 3, 8, ['char', 0x0600, 0x06ff]]]],
+    [
+      'mixed',
+      [
+        'str',
+        [
+          'list',
+          ['repeat', 2, 5, ['char', 65, 90]],
+          ' ',
+          ['char', 0x1f600, 0x1f64f],
+          ' ',
+          ['repeat', 2, 5, ['char', 0x4e00, 0x9fff]],
+        ],
+      ],
+    ],
+  ],
+];
+
+export const largeNumbers: ObjectTemplate = [
+  'obj',
+  [
+    ['maxSafeInteger', ['lit', Number.MAX_SAFE_INTEGER]],
+    ['minSafeInteger', ['lit', Number.MIN_SAFE_INTEGER]],
+    ['largeFloat', ['float', 1e10, 1e15]],
+    ['smallFloat', ['float', 1e-10, 1e-5]],
+    ['preciseDecimal', ['float', 0.000001, 0.999999]],
+    ['scientificNotation', ['lit', 1.23e-45]],
+  ],
+];
+
+export const performanceTest: ArrayTemplate = [
+  'arr',
+  100,
+  1000,
+  [
+    'obj',
+    [
+      ['id', ['int', 1, 1000000]],
+      ['data', ['str', ['repeat', 50, 200, ['char', 32, 126]]]],
+      ['nested', ['obj', [['level1', ['obj', [['level2', ['obj', [['level3', ['arr', 5, 10, 'int']]]]]]]]]]],
+    ],
+  ],
+];
+
+export const mixedTypes: Template = [
+  'or',
+  'str',
+  'int',
+  'float',
+  'bool',
+  'nil',
+  ['arr', 1, 3, 'str'],
+  [
+    'obj',
+    [
+      ['key1', 'str'],
+      ['key2', 'int'],
+    ],
+  ],
+];
+
+// ============================================================================
+// Load Testing Templates (from README examples)
+// ============================================================================
+
+export const loadTestUser: ObjectTemplate = [
+  'obj',
+  [
+    ['id', ['int', 1, 10000]],
+    [
+      'name',
+      [
+        'str',
+        [
+          'list',
+          ['pick', 'John', 'Jane', 'Bob', 'Alice', 'Charlie'],
+          ' ',
+          ['pick', 'Doe', 'Smith', 'Johnson', 'Brown'],
+        ],
+      ],
+    ],
+    ['email', ['str', ['list', ['repeat', 3, 10, ['char', 97, 122]], '@test.com']]],
+    ['age', ['int', 18, 65]],
+    ['active', 'bool'],
+  ],
+];
+
+// ============================================================================
+// Combined Template using 'or' to randomly pick from all examples
+// ============================================================================
+
+export const allExamples: Template = [
+  'or',
+  userProfile,
+  userBasic,
+  apiResponse,
+  apiResponseDetailed,
+  serviceConfig,
+  product,
+  order,
+  userToken,
+  userRole,
+  logEntry,
+  metricData,
+  address,
+  location,
+  transaction,
+  bankAccount,
+  socialPost,
+  socialProfile,
+  sensorReading,
+  iotDevice,
+  patient,
+  medicalRecord,
+  student,
+  course,
+  grade,
+  emptyStructures,
+  unicodeText,
+  largeNumbers,
+  performanceTest,
+  mixedTypes,
+  loadTestUser,
+  tree,
+  comment,
+];
+
+// ============================================================================
+// Helper Methods for Easy Random JSON Generation
+// ============================================================================
+
+/**
+ * Generate a random user profile with comprehensive details.
+ * @returns Random user profile object
+ */
+export const genUser = () => TemplateJson.gen(userProfile);
+
+/**
+ * Generate a basic user object with essential information.
+ * @returns Random basic user object
+ */
+export const genUserBasic = () => TemplateJson.gen(userBasic);
+
+/**
+ * Generate a random address object with street, city, state, etc.
+ * @returns Random address object
+ */
+export const genAddress = () => TemplateJson.gen(address);
+
+/**
+ * Generate a random product with details like name, price, category.
+ * @returns Random product object
+ */
+export const genProduct = () => TemplateJson.gen(product);
+
+/**
+ * Generate a random order with items, customer info, and totals.
+ * @returns Random order object
+ */
+export const genOrder = () => TemplateJson.gen(order);
+
+/**
+ * Generate a random financial transaction.
+ * @returns Random transaction object
+ */
+export const genTransaction = () => TemplateJson.gen(transaction);
+
+/**
+ * Generate a random bank account information.
+ * @returns Random bank account object
+ */
+export const genBankAccount = () => TemplateJson.gen(bankAccount);
+
+/**
+ * Generate a random social media post.
+ * @returns Random social post object
+ */
+export const genSocialPost = () => TemplateJson.gen(socialPost);
+
+/**
+ * Generate a random social media profile.
+ * @returns Random social profile object
+ */
+export const genSocialProfile = () => TemplateJson.gen(socialProfile);
+
+/**
+ * Generate a random location with coordinates and details.
+ * @returns Random location object
+ */
+export const genLocation = () => TemplateJson.gen(location);
+
+/**
+ * Generate a random API response with data array.
+ * @returns Random API response object
+ */
+export const genApiResponse = () => TemplateJson.gen(apiResponse);
+
+/**
+ * Generate a detailed API response with comprehensive metadata.
+ * @returns Random detailed API response object
+ */
+export const genApiResponseDetailed = () => TemplateJson.gen(apiResponseDetailed);
+
+/**
+ * Generate a random service configuration.
+ * @returns Random service config object
+ */
+export const genServiceConfig = () => TemplateJson.gen(serviceConfig);
+
+/**
+ * Generate a random medical patient record.
+ * @returns Random patient object
+ */
+export const genPatient = () => TemplateJson.gen(patient);
+
+/**
+ * Generate a comprehensive medical record.
+ * @returns Random medical record object
+ */
+export const genMedicalRecord = () => TemplateJson.gen(medicalRecord);
+
+/**
+ * Generate a random student profile.
+ * @returns Random student object
+ */
+export const genStudent = () => TemplateJson.gen(student);
+
+/**
+ * Generate a random course information.
+ * @returns Random course object
+ */
+export const genCourse = () => TemplateJson.gen(course);
+
+/**
+ * Generate a random IoT sensor reading.
+ * @returns Random sensor reading object
+ */
+export const genSensorReading = () => TemplateJson.gen(sensorReading);
+
+/**
+ * Generate a random IoT device profile.
+ * @returns Random IoT device object
+ */
+export const genIotDevice = () => TemplateJson.gen(iotDevice);
+
+/**
+ * Generate a random log entry for monitoring.
+ * @returns Random log entry object
+ */
+export const genLogEntry = () => TemplateJson.gen(logEntry);
+
+/**
+ * Generate random metric data for monitoring.
+ * @returns Random metric data object
+ */
+export const genMetricData = () => TemplateJson.gen(metricData);
+
+/**
+ * Generate a random example from any of the available templates.
+ * Uses the 'or' pattern to randomly select from all templates.
+ * @returns Random example data from any template
+ */
+export const genRandomExample = () => TemplateJson.gen(allExamples);
diff --git a/src/structured/__tests__/templates.spec.ts b/src/structured/__tests__/templates.spec.ts
new file mode 100644
index 0000000..89dae91
--- /dev/null
+++ b/src/structured/__tests__/templates.spec.ts
@@ -0,0 +1,291 @@
+import {resetMathRandom} from '../../__tests__/setup';
+import {deterministic} from '../../util';
+import {TemplateJson} from '../TemplateJson';
+import * as templates from '../../examples';
+
+describe('Template Examples', () => {
+  describe('String Pattern Templates', () => {
+    test('generates email addresses', () => {
+      deterministic(123, () => {
+        const email = TemplateJson.gen(['str', templates.tokenEmail]) as string;
+        expect(typeof email).toBe('string');
+        expect(email).toContain('@');
+        expect(email.length).toBeGreaterThan(5);
+      });
+    });
+
+    test('generates phone numbers', () => {
+      deterministic(456, () => {
+        const phone = TemplateJson.gen(['str', templates.tokenPhone]) as string;
+        expect(typeof phone).toBe('string');
+        expect(phone).toMatch(/^\+1-\d{3}-\d{3}-\d{4}$/);
+      });
+    });
+
+    test('generates product codes', () => {
+      deterministic(789, () => {
+        const code = TemplateJson.gen(['str', templates.tokenProductCode]) as string;
+        expect(typeof code).toBe('string');
+        expect(code).toMatch(/^(PRD|ITM|SKU)-[A-Z]{2}\d{6}$/);
+      });
+    });
+
+    test('generates URLs', () => {
+      deterministic(101, () => {
+        const url = TemplateJson.gen(['str', templates.tokenUrl]) as string;
+        expect(typeof url).toBe('string');
+        expect(url).toMatch(/^https:\/\/.*\.(com|org|net|io)/);
+      });
+    });
+  });
+
+  describe('User Profile Templates', () => {
+    test('generates user profile with all required fields', () => {
+      deterministic(202, () => {
+        const user = TemplateJson.gen(templates.userProfile) as any;
+        expect(user).toHaveProperty('id');
+        expect(user).toHaveProperty('username');
+        expect(user).toHaveProperty('email');
+        expect(user).toHaveProperty('age');
+        expect(user).toHaveProperty('isActive');
+        expect(user).toHaveProperty('profile');
+        expect(typeof user.id).toBe('number');
+        expect(typeof user.username).toBe('string');
+        expect(typeof user.email).toBe('string');
+        expect(typeof user.age).toBe('number');
+        expect(typeof user.isActive).toBe('boolean');
+        expect(user.age).toBeGreaterThanOrEqual(18);
+        expect(user.age).toBeLessThanOrEqual(120);
+      });
+    });
+
+    test('generates basic user with required fields', () => {
+      deterministic(303, () => {
+        const user = TemplateJson.gen(templates.userBasic) as any;
+        expect(user).toHaveProperty('id');
+        expect(user).toHaveProperty('name');
+        expect(user).toHaveProperty('active');
+        expect(typeof user.id).toBe('number');
+        expect(typeof user.name).toBe('string');
+        expect(typeof user.active).toBe('boolean');
+        expect(user.name).toContain(' '); // Should have first and last name
+      });
+    });
+  });
+
+  describe('API Response Templates', () => {
+    test('generates API response with correct structure', () => {
+      deterministic(404, () => {
+        const response = TemplateJson.gen(templates.apiResponse) as any;
+        expect(response).toHaveProperty('status');
+        expect(response).toHaveProperty('timestamp');
+        expect(response).toHaveProperty('data');
+        expect(['success', 'error']).toContain(response.status);
+        expect(typeof response.timestamp).toBe('number');
+        expect(Array.isArray(response.data)).toBe(true);
+      });
+    });
+  });
+
+  describe('E-commerce Templates', () => {
+    test('generates product with all fields', () => {
+      deterministic(505, () => {
+        const product = TemplateJson.gen(templates.product) as any;
+        expect(product).toHaveProperty('id');
+        expect(product).toHaveProperty('name');
+        expect(product).toHaveProperty('price');
+        expect(product).toHaveProperty('currency');
+        expect(product).toHaveProperty('category');
+        expect(product).toHaveProperty('tags');
+        expect(product).toHaveProperty('inventory');
+        expect(product).toHaveProperty('rating');
+        expect(product).toHaveProperty('reviews');
+
+        expect(typeof product.id).toBe('string');
+        expect(product.id).toMatch(/^prod_\d{8}$/);
+        expect(typeof product.price).toBe('number');
+        expect(product.price).toBeGreaterThanOrEqual(9.99);
+        expect(Array.isArray(product.tags)).toBe(true);
+        expect(product.inventory).toHaveProperty('stock');
+        expect(product.rating).toBeGreaterThanOrEqual(1.0);
+        expect(product.rating).toBeLessThanOrEqual(5.0);
+      });
+    });
+
+    test('generates order with items', () => {
+      deterministic(606, () => {
+        const order = TemplateJson.gen(templates.order) as any;
+        expect(order).toHaveProperty('orderId');
+        expect(order).toHaveProperty('customerId');
+        expect(order).toHaveProperty('items');
+        expect(order).toHaveProperty('total');
+        expect(order).toHaveProperty('status');
+        expect(order).toHaveProperty('shippingAddress');
+
+        expect(order.orderId).toMatch(/^ORD-\d{10}$/);
+        expect(order.customerId).toMatch(/^CUST-[A-Z]{3}\d{6}$/);
+        expect(Array.isArray(order.items)).toBe(true);
+        expect(order.items.length).toBeGreaterThan(0);
+        expect(order.shippingAddress).toHaveProperty('street');
+        expect(order.shippingAddress).toHaveProperty('city');
+        expect(order.shippingAddress).toHaveProperty('state');
+        expect(order.shippingAddress).toHaveProperty('zipCode');
+      });
+    });
+  });
+
+  describe('Recursive Templates', () => {
+    test('generates tree structure', () => {
+      deterministic(707, () => {
+        const tree = TemplateJson.gen(templates.tree()) as any;
+        expect(tree).toHaveProperty('value');
+        expect(typeof tree.value).toBe('number');
+        // Tree may or may not have left/right children due to probability
+      });
+    });
+
+    test('generates comment thread', () => {
+      deterministic(808, () => {
+        const comment = TemplateJson.gen(templates.comment()) as any;
+        expect(comment).toHaveProperty('id');
+        expect(comment).toHaveProperty('text');
+        expect(comment).toHaveProperty('author');
+        expect(typeof comment.id).toBe('number');
+        expect(typeof comment.text).toBe('string');
+        expect(typeof comment.author).toBe('string');
+        // Replies may or may not exist due to probability
+      });
+    });
+  });
+
+  describe('IoT & Sensor Templates', () => {
+    test('generates sensor reading', () => {
+      deterministic(909, () => {
+        const reading = TemplateJson.gen(templates.sensorReading) as any;
+        expect(reading).toHaveProperty('sensorId');
+        expect(reading).toHaveProperty('deviceType');
+        expect(reading).toHaveProperty('value');
+        expect(reading).toHaveProperty('unit');
+        expect(reading).toHaveProperty('timestamp');
+        expect(reading).toHaveProperty('location');
+        expect(reading).toHaveProperty('status');
+
+        expect(reading.sensorId).toMatch(/^sensor_[A-Z]{2}\d{6}$/);
+        expect(typeof reading.value).toBe('number');
+        expect(reading.value).toBeGreaterThanOrEqual(-50);
+        expect(reading.value).toBeLessThanOrEqual(150);
+        expect(reading.location).toHaveProperty('room');
+        expect(reading.location).toHaveProperty('floor');
+      });
+    });
+  });
+
+  describe('Medical Templates', () => {
+    test('generates patient record', () => {
+      deterministic(1010, () => {
+        const patient = TemplateJson.gen(templates.patient) as any;
+        expect(patient).toHaveProperty('patientId');
+        expect(patient).toHaveProperty('firstName');
+        expect(patient).toHaveProperty('lastName');
+        expect(patient).toHaveProperty('dateOfBirth');
+        expect(patient).toHaveProperty('gender');
+        expect(patient).toHaveProperty('bloodType');
+        expect(patient).toHaveProperty('allergies');
+        expect(patient).toHaveProperty('emergencyContact');
+
+        expect(patient.patientId).toMatch(/^PAT-\d{8}$/);
+        expect(typeof patient.firstName).toBe('string');
+        expect(typeof patient.lastName).toBe('string');
+        expect(Array.isArray(patient.allergies)).toBe(true);
+        expect(patient.emergencyContact).toHaveProperty('name');
+        expect(patient.emergencyContact).toHaveProperty('relationship');
+        expect(patient.emergencyContact).toHaveProperty('phone');
+      });
+    });
+  });
+
+  describe('Edge Case Templates', () => {
+    test('generates empty structures', () => {
+      const empty = TemplateJson.gen(templates.emptyStructures) as any;
+      expect(empty).toHaveProperty('emptyObject');
+      expect(empty).toHaveProperty('emptyArray');
+      expect(empty).toHaveProperty('emptyString');
+      expect(empty).toHaveProperty('nullValue');
+      expect(empty).toHaveProperty('zeroNumber');
+      expect(empty).toHaveProperty('falseBool');
+
+      expect(empty.emptyObject).toEqual({});
+      expect(empty.emptyArray).toEqual([]);
+      expect(empty.emptyString).toBe('');
+      expect(empty.nullValue).toBeNull();
+      expect(empty.zeroNumber).toBe(0);
+      expect(empty.falseBool).toBe(false);
+    });
+
+    test('generates unicode text', () => {
+      deterministic(1111, () => {
+        const unicode = TemplateJson.gen(templates.unicodeText) as any;
+        expect(unicode).toHaveProperty('ascii');
+        expect(unicode).toHaveProperty('latin');
+        expect(unicode).toHaveProperty('emoji');
+        expect(unicode).toHaveProperty('chinese');
+        expect(unicode).toHaveProperty('arabic');
+        expect(unicode).toHaveProperty('mixed');
+
+        expect(typeof unicode.ascii).toBe('string');
+        expect(typeof unicode.emoji).toBe('string');
+        expect(typeof unicode.mixed).toBe('string');
+      });
+    });
+
+    test('generates large numbers', () => {
+      const large = TemplateJson.gen(templates.largeNumbers) as any;
+      expect(large).toHaveProperty('maxSafeInteger');
+      expect(large).toHaveProperty('minSafeInteger');
+      expect(large).toHaveProperty('largeFloat');
+      expect(large).toHaveProperty('smallFloat');
+      expect(large).toHaveProperty('preciseDecimal');
+      expect(large).toHaveProperty('scientificNotation');
+
+      expect(large.maxSafeInteger).toBe(Number.MAX_SAFE_INTEGER);
+      expect(large.minSafeInteger).toBe(Number.MIN_SAFE_INTEGER);
+      expect(typeof large.largeFloat).toBe('number');
+      expect(typeof large.smallFloat).toBe('number');
+      expect(large.scientificNotation).toBe(1.23e-45);
+    });
+
+    test('generates mixed types with or template', () => {
+      deterministic(1212, () => {
+        // Test multiple times to see different types
+        const values = [];
+        for (let i = 0; i < 10; i++) {
+          values.push(TemplateJson.gen(templates.mixedTypes));
+        }
+
+        // Should have generated different types
+        const types = new Set(values.map((v) => typeof v));
+        expect(types.size).toBeGreaterThan(1);
+      });
+    });
+  });
+
+  describe('Combined Template', () => {
+    test('generates data from allExamples template using or', () => {
+      deterministic(9999, () => {
+        // Test multiple times to ensure it can generate different types
+        const results = [];
+        for (let i = 0; i < 20; i++) {
+          const result = TemplateJson.gen(templates.allExamples);
+          results.push(result);
+          expect(result).toBeDefined();
+          expect(typeof result).toBe('object');
+        }
+
+        // Should have generated some variety (not all identical)
+        const stringified = results.map((r) => JSON.stringify(r));
+        const unique = new Set(stringified);
+        expect(unique.size).toBeGreaterThan(1);
+      });
+    });
+  });
+});