diff --git a/packages/dynamite/lib/src/models/components.dart b/packages/dynamite/lib/src/models/components.dart
index 2796da62..e995236a 100644
--- a/packages/dynamite/lib/src/models/components.dart
+++ b/packages/dynamite/lib/src/models/components.dart
@@ -7,8 +7,8 @@ part 'components.g.dart';
 @JsonSerializable()
 class Components {
   Components({
-    required this.securitySchemes,
-    required this.schemas,
+    this.securitySchemes,
+    this.schemas,
   });
 
   factory Components.fromJson(final Map<String, dynamic> json) => _$ComponentsFromJson(json);
diff --git a/packages/dynamite/lib/src/models/header.dart b/packages/dynamite/lib/src/models/header.dart
new file mode 100644
index 00000000..9bd47efa
--- /dev/null
+++ b/packages/dynamite/lib/src/models/header.dart
@@ -0,0 +1,22 @@
+import 'package:dynamite/src/models/schema.dart';
+import 'package:json_annotation/json_annotation.dart';
+
+part 'header.g.dart';
+
+@JsonSerializable()
+class Header {
+  Header({
+    this.description,
+    this.required,
+    this.schema,
+  });
+
+  factory Header.fromJson(final Map<String, dynamic> json) => _$HeaderFromJson(json);
+  Map<String, dynamic> toJson() => _$HeaderToJson(this);
+
+  final String? description;
+
+  final bool? required;
+
+  final Schema? schema;
+}
diff --git a/packages/dynamite/lib/src/models/header.g.dart b/packages/dynamite/lib/src/models/header.g.dart
new file mode 100644
index 00000000..48c2212b
--- /dev/null
+++ b/packages/dynamite/lib/src/models/header.g.dart
@@ -0,0 +1,34 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+part of 'header.dart';
+
+// **************************************************************************
+// JsonSerializableGenerator
+// **************************************************************************
+
+Header _$HeaderFromJson(Map<String, dynamic> json) {
+  $checkKeys(
+    json,
+    allowedKeys: const ['description', 'required', 'schema'],
+  );
+  return Header(
+    description: json['description'] as String?,
+    required: json['required'] as bool?,
+    schema: json['schema'] == null ? null : Schema.fromJson(json['schema'] as Map<String, dynamic>),
+  );
+}
+
+Map<String, dynamic> _$HeaderToJson(Header instance) {
+  final val = <String, dynamic>{};
+
+  void writeNotNull(String key, dynamic value) {
+    if (value != null) {
+      val[key] = value;
+    }
+  }
+
+  writeNotNull('description', instance.description);
+  writeNotNull('required', instance.required);
+  writeNotNull('schema', instance.schema?.toJson());
+  return val;
+}
diff --git a/packages/dynamite/lib/src/models/info.dart b/packages/dynamite/lib/src/models/info.dart
index ff727f2b..59d2f97a 100644
--- a/packages/dynamite/lib/src/models/info.dart
+++ b/packages/dynamite/lib/src/models/info.dart
@@ -8,8 +8,8 @@ class Info {
   Info({
     required this.title,
     required this.version,
-    required this.description,
     required this.license,
+    this.description,
   });
 
   factory Info.fromJson(final Map<String, dynamic> json) => _$InfoFromJson(json);
@@ -19,7 +19,7 @@ class Info {
 
   final String version;
 
-  final String? description;
-
   final License license;
+
+  final String? description;
 }
diff --git a/packages/dynamite/lib/src/models/info.g.dart b/packages/dynamite/lib/src/models/info.g.dart
index 84e3239b..e25d100e 100644
--- a/packages/dynamite/lib/src/models/info.g.dart
+++ b/packages/dynamite/lib/src/models/info.g.dart
@@ -9,13 +9,13 @@ part of 'info.dart';
 Info _$InfoFromJson(Map<String, dynamic> json) {
   $checkKeys(
     json,
-    allowedKeys: const ['title', 'version', 'description', 'license'],
+    allowedKeys: const ['title', 'version', 'license', 'description'],
   );
   return Info(
     title: json['title'] as String,
     version: json['version'] as String,
-    description: json['description'] as String?,
     license: License.fromJson(json['license'] as Map<String, dynamic>),
+    description: json['description'] as String?,
   );
 }
 
@@ -23,6 +23,7 @@ Map<String, dynamic> _$InfoToJson(Info instance) {
   final val = <String, dynamic>{
     'title': instance.title,
     'version': instance.version,
+    'license': instance.license.toJson(),
   };
 
   void writeNotNull(String key, dynamic value) {
@@ -32,6 +33,5 @@ Map<String, dynamic> _$InfoToJson(Info instance) {
   }
 
   writeNotNull('description', instance.description);
-  val['license'] = instance.license.toJson();
   return val;
 }
diff --git a/packages/dynamite/lib/src/models/license.dart b/packages/dynamite/lib/src/models/license.dart
index 00dbb0cd..3bf19718 100644
--- a/packages/dynamite/lib/src/models/license.dart
+++ b/packages/dynamite/lib/src/models/license.dart
@@ -6,8 +6,8 @@ part 'license.g.dart';
 class License {
   License({
     required this.name,
-    required this.identifier,
-    required this.url,
+    this.identifier,
+    this.url,
   });
 
   factory License.fromJson(final Map<String, dynamic> json) => _$LicenseFromJson(json);
diff --git a/packages/dynamite/lib/src/models/media_type.dart b/packages/dynamite/lib/src/models/media_type.dart
index 798ad5d9..4172cbae 100644
--- a/packages/dynamite/lib/src/models/media_type.dart
+++ b/packages/dynamite/lib/src/models/media_type.dart
@@ -6,7 +6,7 @@ part 'media_type.g.dart';
 @JsonSerializable()
 class MediaType {
   MediaType({
-    required this.schema,
+    this.schema,
   });
 
   factory MediaType.fromJson(final Map<String, dynamic> json) => _$MediaTypeFromJson(json);
diff --git a/packages/dynamite/lib/src/models/open_api.dart b/packages/dynamite/lib/src/models/open_api.dart
index 08c51755..45101099 100644
--- a/packages/dynamite/lib/src/models/open_api.dart
+++ b/packages/dynamite/lib/src/models/open_api.dart
@@ -14,11 +14,11 @@ class OpenAPI {
   OpenAPI({
     required this.version,
     required this.info,
-    required this.servers,
-    required this.security,
-    required this.tags,
-    required this.components,
-    required this.paths,
+    this.servers,
+    this.security,
+    this.tags,
+    this.components,
+    this.paths,
   });
 
   factory OpenAPI.fromJson(final Map<String, dynamic> json) => _$OpenAPIFromJson(json);
diff --git a/packages/dynamite/lib/src/models/operation.dart b/packages/dynamite/lib/src/models/operation.dart
index d1590a3d..54b9d696 100644
--- a/packages/dynamite/lib/src/models/operation.dart
+++ b/packages/dynamite/lib/src/models/operation.dart
@@ -9,11 +9,11 @@ part 'operation.g.dart';
 @JsonSerializable()
 class Operation {
   Operation({
-    required this.operationId,
-    required this.tags,
-    required this.parameters,
-    required this.requestBody,
-    required this.responses,
+    this.operationId,
+    this.tags,
+    this.parameters,
+    this.requestBody,
+    this.responses,
   });
 
   factory Operation.fromJson(final Map<String, dynamic> json) => _$OperationFromJson(json);
diff --git a/packages/dynamite/lib/src/models/parameter.dart b/packages/dynamite/lib/src/models/parameter.dart
index a3d309df..86dc7340 100644
--- a/packages/dynamite/lib/src/models/parameter.dart
+++ b/packages/dynamite/lib/src/models/parameter.dart
@@ -8,9 +8,9 @@ class Parameter {
   Parameter({
     required this.name,
     required this.in_,
-    required this.description,
-    required this.required,
-    required this.schema,
+    this.description,
+    this.required,
+    this.schema,
   });
 
   factory Parameter.fromJson(final Map<String, dynamic> json) => _$ParameterFromJson(json);
diff --git a/packages/dynamite/lib/src/models/path_item.dart b/packages/dynamite/lib/src/models/path_item.dart
index 8684f923..5d75e819 100644
--- a/packages/dynamite/lib/src/models/path_item.dart
+++ b/packages/dynamite/lib/src/models/path_item.dart
@@ -7,16 +7,16 @@ part 'path_item.g.dart';
 @JsonSerializable()
 class PathItem {
   PathItem({
-    required this.description,
-    required this.parameters,
-    required this.get,
-    required this.put,
-    required this.post,
-    required this.delete,
-    required this.options,
-    required this.head,
-    required this.patch,
-    required this.trace,
+    this.description,
+    this.parameters,
+    this.get,
+    this.put,
+    this.post,
+    this.delete,
+    this.options,
+    this.head,
+    this.patch,
+    this.trace,
   });
 
   factory PathItem.fromJson(final Map<String, dynamic> json) => _$PathItemFromJson(json);
diff --git a/packages/dynamite/lib/src/models/request_body.dart b/packages/dynamite/lib/src/models/request_body.dart
index 3ed03da9..1fbe60eb 100644
--- a/packages/dynamite/lib/src/models/request_body.dart
+++ b/packages/dynamite/lib/src/models/request_body.dart
@@ -6,9 +6,9 @@ part 'request_body.g.dart';
 @JsonSerializable()
 class RequestBody {
   RequestBody({
-    required this.description,
-    required this.content,
-    required this.required,
+    this.description,
+    this.content,
+    this.required,
   });
 
   factory RequestBody.fromJson(final Map<String, dynamic> json) => _$RequestBodyFromJson(json);
diff --git a/packages/dynamite/lib/src/models/response.dart b/packages/dynamite/lib/src/models/response.dart
index 9a917517..693e35c9 100644
--- a/packages/dynamite/lib/src/models/response.dart
+++ b/packages/dynamite/lib/src/models/response.dart
@@ -1,3 +1,4 @@
+import 'package:dynamite/src/models/header.dart';
 import 'package:dynamite/src/models/media_type.dart';
 import 'package:json_annotation/json_annotation.dart';
 
@@ -7,7 +8,8 @@ part 'response.g.dart';
 class Response {
   Response({
     required this.description,
-    required this.content,
+    this.content,
+    this.headers,
   });
 
   factory Response.fromJson(final Map<String, dynamic> json) => _$ResponseFromJson(json);
@@ -16,4 +18,6 @@ class Response {
   final String description;
 
   final Map<String, MediaType>? content;
+
+  final Map<String, Header>? headers;
 }
diff --git a/packages/dynamite/lib/src/models/response.g.dart b/packages/dynamite/lib/src/models/response.g.dart
index 47ef4691..10b887ef 100644
--- a/packages/dynamite/lib/src/models/response.g.dart
+++ b/packages/dynamite/lib/src/models/response.g.dart
@@ -9,13 +9,16 @@ part of 'response.dart';
 Response _$ResponseFromJson(Map<String, dynamic> json) {
   $checkKeys(
     json,
-    allowedKeys: const ['description', 'content'],
+    allowedKeys: const ['description', 'content', 'headers'],
   );
   return Response(
     description: json['description'] as String,
     content: (json['content'] as Map<String, dynamic>?)?.map(
       (k, e) => MapEntry(k, MediaType.fromJson(e as Map<String, dynamic>)),
     ),
+    headers: (json['headers'] as Map<String, dynamic>?)?.map(
+      (k, e) => MapEntry(k, Header.fromJson(e as Map<String, dynamic>)),
+    ),
   );
 }
 
@@ -31,5 +34,6 @@ Map<String, dynamic> _$ResponseToJson(Response instance) {
   }
 
   writeNotNull('content', instance.content?.map((k, e) => MapEntry(k, e.toJson())));
+  writeNotNull('headers', instance.headers?.map((k, e) => MapEntry(k, e.toJson())));
   return val;
 }
diff --git a/packages/dynamite/lib/src/models/schema.dart b/packages/dynamite/lib/src/models/schema.dart
index 0b3e48fd..c6185105 100644
--- a/packages/dynamite/lib/src/models/schema.dart
+++ b/packages/dynamite/lib/src/models/schema.dart
@@ -5,19 +5,19 @@ part 'schema.g.dart';
 @JsonSerializable()
 class Schema {
   Schema({
-    required this.ref,
-    required this.oneOf,
-    required this.anyOf,
-    required this.allOf,
-    required this.description,
-    required this.deprecated,
-    required this.type,
-    required this.format,
-    required this.default_,
-    required this.enum_,
-    required this.properties,
-    required this.required,
-    required this.items,
+    this.ref,
+    this.oneOf,
+    this.anyOf,
+    this.allOf,
+    this.description,
+    this.deprecated,
+    this.type,
+    this.format,
+    this.default_,
+    this.enum_,
+    this.properties,
+    this.required,
+    this.items,
   });
 
   factory Schema.fromJson(final Map<String, dynamic> json) => _$SchemaFromJson(json);
diff --git a/packages/dynamite/lib/src/models/security_scheme.dart b/packages/dynamite/lib/src/models/security_scheme.dart
index 0cc60176..df8b4417 100644
--- a/packages/dynamite/lib/src/models/security_scheme.dart
+++ b/packages/dynamite/lib/src/models/security_scheme.dart
@@ -6,8 +6,8 @@ part 'security_scheme.g.dart';
 class SecurityScheme {
   SecurityScheme({
     required this.type,
-    required this.description,
-    required this.scheme,
+    this.description,
+    this.scheme,
   });
 
   factory SecurityScheme.fromJson(final Map<String, dynamic> json) => _$SecuritySchemeFromJson(json);
diff --git a/packages/dynamite/lib/src/models/server.dart b/packages/dynamite/lib/src/models/server.dart
index 5bd129db..7feeac49 100644
--- a/packages/dynamite/lib/src/models/server.dart
+++ b/packages/dynamite/lib/src/models/server.dart
@@ -7,7 +7,7 @@ part 'server.g.dart';
 class Server {
   Server({
     required this.url,
-    required this.variables,
+    this.variables,
   });
 
   factory Server.fromJson(final Map<String, dynamic> json) => _$ServerFromJson(json);
diff --git a/packages/dynamite/lib/src/models/server_variable.dart b/packages/dynamite/lib/src/models/server_variable.dart
index f41240aa..52788812 100644
--- a/packages/dynamite/lib/src/models/server_variable.dart
+++ b/packages/dynamite/lib/src/models/server_variable.dart
@@ -6,8 +6,8 @@ part 'server_variable.g.dart';
 class ServerVariable {
   ServerVariable({
     required this.default_,
-    required this.enum_,
-    required this.description,
+    this.enum_,
+    this.description,
   });
 
   factory ServerVariable.fromJson(final Map<String, dynamic> json) => _$ServerVariableFromJson(json);