diff --git a/Chapter06/MyBlog/Data.Models/Models/BlogPost.cs b/Chapter06/MyBlog/Data.Models/Models/BlogPost.cs
index 9cd16ee..f0bb350 100644
--- a/Chapter06/MyBlog/Data.Models/Models/BlogPost.cs
+++ b/Chapter06/MyBlog/Data.Models/Models/BlogPost.cs
@@ -1,9 +1,12 @@
 namespace Data.Models;
-
+using System.ComponentModel.DataAnnotations;
 public class BlogPost
 {
     public string? Id { get; set; }
+    [MinLength(5)]
+    [Required]
     public string Title { get; set; } = string.Empty;
+    [Required]
     public string Text { get; set; } = string.Empty;
     public DateTime PublishDate { get; set; }
     public Category? Category { get; set; }
diff --git a/Chapter07/MyBlog/Data.Models/Models/Category.cs b/Chapter07/MyBlog/Data.Models/Models/Category.cs
index 3540843..52bdd21 100644
--- a/Chapter07/MyBlog/Data.Models/Models/Category.cs
+++ b/Chapter07/MyBlog/Data.Models/Models/Category.cs
@@ -2,5 +2,6 @@
 public class Category
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter07/MyBlog/Data.Models/Models/Tag.cs b/Chapter07/MyBlog/Data.Models/Models/Tag.cs
index 604ac84..19430bf 100644
--- a/Chapter07/MyBlog/Data.Models/Models/Tag.cs
+++ b/Chapter07/MyBlog/Data.Models/Models/Tag.cs
@@ -2,5 +2,6 @@
 public class Tag
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter08/MyBlog/Data.Models/Models/Category.cs b/Chapter08/MyBlog/Data.Models/Models/Category.cs
index 3540843..52bdd21 100644
--- a/Chapter08/MyBlog/Data.Models/Models/Category.cs
+++ b/Chapter08/MyBlog/Data.Models/Models/Category.cs
@@ -2,5 +2,6 @@
 public class Category
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter08/MyBlog/Data.Models/Models/Tag.cs b/Chapter08/MyBlog/Data.Models/Models/Tag.cs
index 604ac84..19430bf 100644
--- a/Chapter08/MyBlog/Data.Models/Models/Tag.cs
+++ b/Chapter08/MyBlog/Data.Models/Models/Tag.cs
@@ -2,5 +2,6 @@
 public class Tag
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter09/MyBlog/Data.Models/Models/Category.cs b/Chapter09/MyBlog/Data.Models/Models/Category.cs
index 3540843..52bdd21 100644
--- a/Chapter09/MyBlog/Data.Models/Models/Category.cs
+++ b/Chapter09/MyBlog/Data.Models/Models/Category.cs
@@ -2,5 +2,6 @@
 public class Category
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter09/MyBlog/Data.Models/Models/Tag.cs b/Chapter09/MyBlog/Data.Models/Models/Tag.cs
index 604ac84..19430bf 100644
--- a/Chapter09/MyBlog/Data.Models/Models/Tag.cs
+++ b/Chapter09/MyBlog/Data.Models/Models/Tag.cs
@@ -2,5 +2,6 @@
 public class Tag
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter10/MyBlog/Data.Models/Models/Category.cs b/Chapter10/MyBlog/Data.Models/Models/Category.cs
index 3540843..52bdd21 100644
--- a/Chapter10/MyBlog/Data.Models/Models/Category.cs
+++ b/Chapter10/MyBlog/Data.Models/Models/Category.cs
@@ -2,5 +2,6 @@
 public class Category
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter10/MyBlog/Data.Models/Models/Tag.cs b/Chapter10/MyBlog/Data.Models/Models/Tag.cs
index 604ac84..19430bf 100644
--- a/Chapter10/MyBlog/Data.Models/Models/Tag.cs
+++ b/Chapter10/MyBlog/Data.Models/Models/Tag.cs
@@ -2,5 +2,6 @@
 public class Tag
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter11/MyBlog/Data.Models/Models/Category.cs b/Chapter11/MyBlog/Data.Models/Models/Category.cs
index 3540843..52bdd21 100644
--- a/Chapter11/MyBlog/Data.Models/Models/Category.cs
+++ b/Chapter11/MyBlog/Data.Models/Models/Category.cs
@@ -2,5 +2,6 @@
 public class Category
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter11/MyBlog/Data.Models/Models/Tag.cs b/Chapter11/MyBlog/Data.Models/Models/Tag.cs
index 604ac84..19430bf 100644
--- a/Chapter11/MyBlog/Data.Models/Models/Tag.cs
+++ b/Chapter11/MyBlog/Data.Models/Models/Tag.cs
@@ -2,5 +2,6 @@
 public class Tag
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter12/MyBlog/Data.Models/Models/Category.cs b/Chapter12/MyBlog/Data.Models/Models/Category.cs
index 3540843..52bdd21 100644
--- a/Chapter12/MyBlog/Data.Models/Models/Category.cs
+++ b/Chapter12/MyBlog/Data.Models/Models/Category.cs
@@ -2,5 +2,6 @@
 public class Category
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter12/MyBlog/Data.Models/Models/Tag.cs b/Chapter12/MyBlog/Data.Models/Models/Tag.cs
index 604ac84..19430bf 100644
--- a/Chapter12/MyBlog/Data.Models/Models/Tag.cs
+++ b/Chapter12/MyBlog/Data.Models/Models/Tag.cs
@@ -2,5 +2,6 @@
 public class Tag
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter13/MyBlog/Data.Models/Models/Category.cs b/Chapter13/MyBlog/Data.Models/Models/Category.cs
index 3540843..52bdd21 100644
--- a/Chapter13/MyBlog/Data.Models/Models/Category.cs
+++ b/Chapter13/MyBlog/Data.Models/Models/Category.cs
@@ -2,5 +2,6 @@
 public class Category
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }
diff --git a/Chapter13/MyBlog/Data.Models/Models/Tag.cs b/Chapter13/MyBlog/Data.Models/Models/Tag.cs
index 604ac84..19430bf 100644
--- a/Chapter13/MyBlog/Data.Models/Models/Tag.cs
+++ b/Chapter13/MyBlog/Data.Models/Models/Tag.cs
@@ -2,5 +2,6 @@
 public class Tag
 {
     public string? Id { get; set; }
+    [Required]
     public string Name { get; set; } = string.Empty;
 }