diff --git a/src/main/java/project/bookstore/controller/CategoryController.java b/src/main/java/project/bookstore/controller/CategoryController.java
index 71bd597..e24d46e 100644
--- a/src/main/java/project/bookstore/controller/CategoryController.java
+++ b/src/main/java/project/bookstore/controller/CategoryController.java
@@ -1,8 +1,13 @@
 package project.bookstore.controller;
 
+import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.tags.Tag;
+import jakarta.validation.Valid;
 import java.util.List;
 import lombok.RequiredArgsConstructor;
+import org.springdoc.core.annotations.ParameterObject;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.web.PageableDefault;
 import org.springframework.security.access.prepost.PreAuthorize;
 import org.springframework.web.bind.annotation.DeleteMapping;
 import org.springframework.web.bind.annotation.GetMapping;
@@ -28,36 +33,54 @@ public class CategoryController {
 
     @PreAuthorize("hasRole('ROLE_ADMIN')")
     @PostMapping
-    public CategoryDto createCategory(@RequestBody CategoryRequestDto requestDto) {
+    @Operation(
+            summary = "Create new category",
+            description = "Create new category and add to db")
+    public CategoryDto createCategory(@RequestBody @Valid CategoryRequestDto requestDto) {
         return categoryService.save(requestDto);
     }
 
     @GetMapping
-    public List getAll() {
+    @Operation(
+            summary = "Get all categories",
+            description = "Get all categories from db")
+    public List<CategoryDto> getAll(@ParameterObject @PageableDefault Pageable pageable) {
         return categoryService.findAll();
     }
 
     @GetMapping("/{id}")
+    @Operation(
+            summary = "Get category by id",
+            description = "Get category by id from db")
     public CategoryDto getCategoryById(@PathVariable Long id) {
         return categoryService.getById(id);
     }
 
     @PreAuthorize("hasRole('ROLE_ADMIN')")
     @PutMapping("/{id}")
+    @Operation(
+            summary = "Update category by id",
+            description = "Update category by id in db")
     public CategoryDto updateCategory(
             @PathVariable Long id,
-            @RequestBody CategoryRequestDto categoryRequestDto
+            @RequestBody @Valid CategoryRequestDto categoryRequestDto
     ) {
         return categoryService.update(id, categoryRequestDto);
     }
 
     @PreAuthorize("hasRole('ROLE_ADMIN')")
     @DeleteMapping("/{id}")
+    @Operation(
+            summary = "Delete category by id",
+            description = "Delete category by id from db")
     public void deleteCategory(@PathVariable Long id) {
         categoryService.deleteById(id);
     }
 
     @GetMapping("/{id}/books")
+    @Operation(
+            summary = "Get all books of category",
+            description = "Get all books of category by id from db")
     public List<BookDtoWithoutCategoryIds> getBooksByCategoryId(@PathVariable Long id) {
         return bookService.getAllByCategoriesId(id);
     }
diff --git a/src/main/java/project/bookstore/model/Category.java b/src/main/java/project/bookstore/model/Category.java
index 1e42a0e..5a68477 100644
--- a/src/main/java/project/bookstore/model/Category.java
+++ b/src/main/java/project/bookstore/model/Category.java
@@ -17,7 +17,7 @@ public class Category {
     @Id
     @GeneratedValue(strategy = GenerationType.IDENTITY)
     private Long id;
-    @Column(unique = true)
+    @Column(nullable = false, unique = true)
     private String name;
     private String description;
 }
diff --git a/src/main/java/project/bookstore/repository/category/CategoryRepository.java b/src/main/java/project/bookstore/repository/category/CategoryRepository.java
index ca65a17..a7a0133 100644
--- a/src/main/java/project/bookstore/repository/category/CategoryRepository.java
+++ b/src/main/java/project/bookstore/repository/category/CategoryRepository.java
@@ -4,5 +4,4 @@
 import project.bookstore.model.Category;
 
 public interface CategoryRepository extends JpaRepository<Category, Long> {
-    //Category updateCategoryById(Long id, Category category);
 }
diff --git a/src/main/java/project/bookstore/service/CategoryService.java b/src/main/java/project/bookstore/service/CategoryService.java
index 5bf4d00..5a62256 100644
--- a/src/main/java/project/bookstore/service/CategoryService.java
+++ b/src/main/java/project/bookstore/service/CategoryService.java
@@ -5,7 +5,7 @@
 import project.bookstore.dto.category.CategoryRequestDto;
 
 public interface CategoryService {
-    List findAll();
+    List<CategoryDto> findAll();
 
     CategoryDto getById(Long id);
 
diff --git a/src/main/java/project/bookstore/service/impl/CategoryServiceImpl.java b/src/main/java/project/bookstore/service/impl/CategoryServiceImpl.java
index 9e72967..e9a3249 100644
--- a/src/main/java/project/bookstore/service/impl/CategoryServiceImpl.java
+++ b/src/main/java/project/bookstore/service/impl/CategoryServiceImpl.java
@@ -18,8 +18,11 @@ public class CategoryServiceImpl implements CategoryService {
     private final CategoryMapper categoryMapper;
 
     @Override
-    public List findAll() {
-        return categoryRepository.findAll();
+    public List<CategoryDto> findAll() {
+        return categoryRepository.findAll()
+                .stream()
+                .map(categoryMapper::toDto)
+                .toList();
     }
 
     @Override