diff --git a/src/components/schemas/project.simple.yml b/src/components/schemas/project.simple.yml
new file mode 100644
index 0000000..1d7da55
--- /dev/null
+++ b/src/components/schemas/project.simple.yml
@@ -0,0 +1,59 @@
+type: object
+required:
+  - id
+  - name
+  - identifier
+  - description
+  - status
+  - is_public
+  - inherit_members
+  - created_on
+  - updated_on
+properties:
+  id:
+    type: integer
+  name:
+    type: string
+  identifier:
+    type: string
+  description:
+    type: string
+    nullable: true
+  parent:
+    $ref: ./id_name.yml
+  status:
+    type: integer
+  is_public:
+    type: boolean
+  inherit_members:
+    type: boolean
+  custom_fields:
+    type: array
+    items:
+      $ref: ./custom_field_value.yml
+  trackers:
+    type: array
+    items:
+      $ref: ./id_name.yml
+  issue_categories:
+    type: array
+    items:
+      $ref: ./id_name.yml
+  time_entry_activities:
+    type: array
+    items:
+      $ref: ./id_name.yml
+  enabled_modules:
+    type: array
+    items:
+      $ref: ./id_name.yml
+  issue_custom_fields:
+    type: array
+    items:
+      $ref: ./id_name.yml
+  created_on:
+    type: string
+    format: date-time
+  updated_on:
+    type: string
+    format: date-time
diff --git a/src/components/schemas/project.yml b/src/components/schemas/project.yml
index e7a46cc..1f25fbc 100644
--- a/src/components/schemas/project.yml
+++ b/src/components/schemas/project.yml
@@ -22,14 +22,18 @@ properties:
   homepage:
     type: string
     nullable: true
-  parent_id:
-    type: integer
+  parent:
+    $ref: ./id_name.yml
   status:
     type: integer
   is_public:
     type: boolean
   inherit_members:
     type: boolean
+  default_version:
+    $ref: ./id_name.yml
+  default_assignee:
+    $ref: ./id_name.yml
   custom_fields:
     type: array
     items:
@@ -42,11 +46,11 @@ properties:
     type: array
     items:
       $ref: ./id_name.yml
-  enabled_modules:
+  time_entry_activities:
     type: array
     items:
       $ref: ./id_name.yml
-  time_entry_activities:
+  enabled_modules:
     type: array
     items:
       $ref: ./id_name.yml
diff --git a/src/openapi.yml b/src/openapi.yml
index deaf5ed..35a362b 100644
--- a/src/openapi.yml
+++ b/src/openapi.yml
@@ -9,7 +9,7 @@ info:
   license:
     name: MIT
     url: https://github.com/d-yoshi/redmine-openapi/blob/main/LICENSE
-  version: 0.13.5
+  version: 0.14.0
 
 servers:
   - url: /
diff --git a/src/paths/projects.project_id.yml b/src/paths/projects.project_id.yml
index e9ddd08..c8ec6ff 100644
--- a/src/paths/projects.project_id.yml
+++ b/src/paths/projects.project_id.yml
@@ -18,8 +18,8 @@ get:
           enum:
             - trackers
             - issue_categories
-            - enabled_modules
             - time_entry_activities
+            - enabled_modules
             - issue_custom_fields
       explode: false
   responses:
@@ -59,18 +59,23 @@ put:
                   type: string
                 description:
                   type: string
+                  nullable: true
                 homepage:
                   type: string
+                  nullable: true
                 is_public:
                   type: boolean
                 parent_id:
                   type: integer
+                  nullable: true
                 inherit_members:
                   type: boolean
                 default_assigned_to_id:
                   type: integer
+                  nullable: true
                 default_version_id:
                   type: integer
+                  nullable: true
                 tracker_ids:
                   type: array
                   items:
diff --git a/src/paths/projects.yml b/src/paths/projects.yml
index b2a6e4a..166a351 100644
--- a/src/paths/projects.yml
+++ b/src/paths/projects.yml
@@ -21,8 +21,8 @@ get:
           enum:
             - trackers
             - issue_categories
-            - enabled_modules
             - time_entry_activities
+            - enabled_modules
             - issue_custom_fields
       explode: false
   responses:
@@ -38,7 +38,7 @@ get:
               projects:
                 type: array
                 items:
-                  $ref: ../components/schemas/project.yml
+                  $ref: ../components/schemas/project.simple.yml
               total_count:
                 type: integer
               offset:
@@ -84,12 +84,15 @@ post:
                   type: boolean
                 parent_id:
                   type: integer
+                  nullable: true
                 inherit_members:
                   type: boolean
                 default_assigned_to_id:
                   type: integer
+                  nullable: true
                 default_version_id:
                   type: integer
+                  nullable: true
                 tracker_ids:
                   type: array
                   items: