diff --git a/codegen/smithy-aws-typescript-codegen/src/main/java/software/amazon/smithy/aws/typescript/codegen/DocumentClientCommandGenerator.java b/codegen/smithy-aws-typescript-codegen/src/main/java/software/amazon/smithy/aws/typescript/codegen/DocumentClientCommandGenerator.java
index ffd8f1e7f296..ad38b391f87a 100644
--- a/codegen/smithy-aws-typescript-codegen/src/main/java/software/amazon/smithy/aws/typescript/codegen/DocumentClientCommandGenerator.java
+++ b/codegen/smithy-aws-typescript-codegen/src/main/java/software/amazon/smithy/aws/typescript/codegen/DocumentClientCommandGenerator.java
@@ -392,11 +392,11 @@ private void writeStructureMemberOmitType(MemberShape member) {
         String optionalSuffix = isRequiredMember(member) ? "" : "?";
         writer.openBlock("${L}${L}: ", ";", symbolProvider.toMemberName(member),
             optionalSuffix, () -> {
-                writeMemberOmitType(member);
+                writeMemberOmitType(member, true);
             });
     }
 
-    private void writeMemberOmitType(MemberShape member) {
+    private void writeMemberOmitType(MemberShape member, boolean allowUndefined) {
         Shape memberTarget = model.expectShape(member.getTarget());
         if (memberTarget.isStructureShape()) {
             writeStructureOmitType((StructureShape) memberTarget);
@@ -413,16 +413,17 @@ private void writeMemberOmitType(MemberShape member) {
         } else if (memberTarget.isMapShape()) {
             MemberShape mapMember = ((MapShape) memberTarget).getValue();
             writer.openBlock("Record<string, ", ">", () -> {
-                writeMemberOmitType(mapMember);
+                writeMemberOmitType(mapMember, false);
             });
         } else if (memberTarget instanceof CollectionShape) {
             MemberShape collectionMember = ((CollectionShape) memberTarget).getMember();
             writer.openBlock("(", ")[]", () -> {
-                writeMemberOmitType(collectionMember);
+                writeMemberOmitType(collectionMember, false);
             });
         }
-        String typeSuffix = isRequiredMember(member) ? " | undefined" : "";
-        writer.write("${L}", typeSuffix);
+        if (allowUndefined) {
+            writer.write(" | undefined");
+        }
     }
 
     private void writeNativeAttributeValue() {
diff --git a/lib/lib-dynamodb/src/commands/BatchExecuteStatementCommand.ts b/lib/lib-dynamodb/src/commands/BatchExecuteStatementCommand.ts
index 2d9e8fecb4a0..2f542799d961 100644
--- a/lib/lib-dynamodb/src/commands/BatchExecuteStatementCommand.ts
+++ b/lib/lib-dynamodb/src/commands/BatchExecuteStatementCommand.ts
@@ -18,7 +18,7 @@ export { DynamoDBDocumentClientCommand, $Command };
 export type BatchExecuteStatementCommandInput = Omit<__BatchExecuteStatementCommandInput, "Statements"> & {
   Statements:
     | (Omit<BatchStatementRequest, "Parameters"> & {
-        Parameters?: NativeAttributeValue[];
+        Parameters?: NativeAttributeValue[] | undefined;
       })[]
     | undefined;
 };
@@ -27,12 +27,16 @@ export type BatchExecuteStatementCommandInput = Omit<__BatchExecuteStatementComm
  * @public
  */
 export type BatchExecuteStatementCommandOutput = Omit<__BatchExecuteStatementCommandOutput, "Responses"> & {
-  Responses?: (Omit<BatchStatementResponse, "Error" | "Item"> & {
-    Error?: Omit<BatchStatementError, "Item"> & {
-      Item?: Record<string, NativeAttributeValue>;
-    };
-    Item?: Record<string, NativeAttributeValue>;
-  })[];
+  Responses?:
+    | (Omit<BatchStatementResponse, "Error" | "Item"> & {
+        Error?:
+          | (Omit<BatchStatementError, "Item"> & {
+              Item?: Record<string, NativeAttributeValue> | undefined;
+            })
+          | undefined;
+        Item?: Record<string, NativeAttributeValue> | undefined;
+      })[]
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/BatchGetCommand.ts b/lib/lib-dynamodb/src/commands/BatchGetCommand.ts
index def798d0a011..b4a371ff9f43 100644
--- a/lib/lib-dynamodb/src/commands/BatchGetCommand.ts
+++ b/lib/lib-dynamodb/src/commands/BatchGetCommand.ts
@@ -30,13 +30,15 @@ export type BatchGetCommandInput = Omit<__BatchGetItemCommandInput, "RequestItem
  * @public
  */
 export type BatchGetCommandOutput = Omit<__BatchGetItemCommandOutput, "Responses" | "UnprocessedKeys"> & {
-  Responses?: Record<string, Record<string, NativeAttributeValue>[]>;
-  UnprocessedKeys?: Record<
-    string,
-    Omit<KeysAndAttributes, "Keys"> & {
-      Keys: Record<string, NativeAttributeValue>[] | undefined;
-    }
-  >;
+  Responses?: Record<string, Record<string, NativeAttributeValue>[]> | undefined;
+  UnprocessedKeys?:
+    | Record<
+        string,
+        Omit<KeysAndAttributes, "Keys"> & {
+          Keys: Record<string, NativeAttributeValue>[] | undefined;
+        }
+      >
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/BatchWriteCommand.ts b/lib/lib-dynamodb/src/commands/BatchWriteCommand.ts
index 9de56da1658b..c82b5fbcc600 100644
--- a/lib/lib-dynamodb/src/commands/BatchWriteCommand.ts
+++ b/lib/lib-dynamodb/src/commands/BatchWriteCommand.ts
@@ -20,12 +20,16 @@ export type BatchWriteCommandInput = Omit<__BatchWriteItemCommandInput, "Request
     | Record<
         string,
         (Omit<WriteRequest, "PutRequest" | "DeleteRequest"> & {
-          PutRequest?: Omit<PutRequest, "Item"> & {
-            Item: Record<string, NativeAttributeValue> | undefined;
-          };
-          DeleteRequest?: Omit<DeleteRequest, "Key"> & {
-            Key: Record<string, NativeAttributeValue> | undefined;
-          };
+          PutRequest?:
+            | (Omit<PutRequest, "Item"> & {
+                Item: Record<string, NativeAttributeValue> | undefined;
+              })
+            | undefined;
+          DeleteRequest?:
+            | (Omit<DeleteRequest, "Key"> & {
+                Key: Record<string, NativeAttributeValue> | undefined;
+              })
+            | undefined;
         })[]
       >
     | undefined;
@@ -38,23 +42,31 @@ export type BatchWriteCommandOutput = Omit<
   __BatchWriteItemCommandOutput,
   "UnprocessedItems" | "ItemCollectionMetrics"
 > & {
-  UnprocessedItems?: Record<
-    string,
-    (Omit<WriteRequest, "PutRequest" | "DeleteRequest"> & {
-      PutRequest?: Omit<PutRequest, "Item"> & {
-        Item: Record<string, NativeAttributeValue> | undefined;
-      };
-      DeleteRequest?: Omit<DeleteRequest, "Key"> & {
-        Key: Record<string, NativeAttributeValue> | undefined;
-      };
-    })[]
-  >;
-  ItemCollectionMetrics?: Record<
-    string,
-    (Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
-      ItemCollectionKey?: Record<string, NativeAttributeValue>;
-    })[]
-  >;
+  UnprocessedItems?:
+    | Record<
+        string,
+        (Omit<WriteRequest, "PutRequest" | "DeleteRequest"> & {
+          PutRequest?:
+            | (Omit<PutRequest, "Item"> & {
+                Item: Record<string, NativeAttributeValue> | undefined;
+              })
+            | undefined;
+          DeleteRequest?:
+            | (Omit<DeleteRequest, "Key"> & {
+                Key: Record<string, NativeAttributeValue> | undefined;
+              })
+            | undefined;
+        })[]
+      >
+    | undefined;
+  ItemCollectionMetrics?:
+    | Record<
+        string,
+        (Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
+          ItemCollectionKey?: Record<string, NativeAttributeValue> | undefined;
+        })[]
+      >
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/DeleteCommand.ts b/lib/lib-dynamodb/src/commands/DeleteCommand.ts
index f6d6e32a15bf..5b7e0161b1a6 100644
--- a/lib/lib-dynamodb/src/commands/DeleteCommand.ts
+++ b/lib/lib-dynamodb/src/commands/DeleteCommand.ts
@@ -17,24 +17,28 @@ export { DynamoDBDocumentClientCommand, $Command };
  */
 export type DeleteCommandInput = Omit<__DeleteItemCommandInput, "Key" | "Expected" | "ExpressionAttributeValues"> & {
   Key: Record<string, NativeAttributeValue> | undefined;
-  Expected?: Record<
-    string,
-    Omit<ExpectedAttributeValue, "Value" | "AttributeValueList"> & {
-      Value?: NativeAttributeValue;
-      AttributeValueList?: NativeAttributeValue[];
-    }
-  >;
-  ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
+  Expected?:
+    | Record<
+        string,
+        Omit<ExpectedAttributeValue, "Value" | "AttributeValueList"> & {
+          Value?: NativeAttributeValue | undefined;
+          AttributeValueList?: NativeAttributeValue[] | undefined;
+        }
+      >
+    | undefined;
+  ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
  * @public
  */
 export type DeleteCommandOutput = Omit<__DeleteItemCommandOutput, "Attributes" | "ItemCollectionMetrics"> & {
-  Attributes?: Record<string, NativeAttributeValue>;
-  ItemCollectionMetrics?: Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
-    ItemCollectionKey?: Record<string, NativeAttributeValue>;
-  };
+  Attributes?: Record<string, NativeAttributeValue> | undefined;
+  ItemCollectionMetrics?:
+    | (Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
+        ItemCollectionKey?: Record<string, NativeAttributeValue> | undefined;
+      })
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/ExecuteStatementCommand.ts b/lib/lib-dynamodb/src/commands/ExecuteStatementCommand.ts
index 81f0aae6227d..3c06c973948c 100644
--- a/lib/lib-dynamodb/src/commands/ExecuteStatementCommand.ts
+++ b/lib/lib-dynamodb/src/commands/ExecuteStatementCommand.ts
@@ -16,15 +16,15 @@ export { DynamoDBDocumentClientCommand, $Command };
  * @public
  */
 export type ExecuteStatementCommandInput = Omit<__ExecuteStatementCommandInput, "Parameters"> & {
-  Parameters?: NativeAttributeValue[];
+  Parameters?: NativeAttributeValue[] | undefined;
 };
 
 /**
  * @public
  */
 export type ExecuteStatementCommandOutput = Omit<__ExecuteStatementCommandOutput, "Items" | "LastEvaluatedKey"> & {
-  Items?: Record<string, NativeAttributeValue>[];
-  LastEvaluatedKey?: Record<string, NativeAttributeValue>;
+  Items?: Record<string, NativeAttributeValue>[] | undefined;
+  LastEvaluatedKey?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/ExecuteTransactionCommand.ts b/lib/lib-dynamodb/src/commands/ExecuteTransactionCommand.ts
index 6e7d40beefc9..4f8831742b2a 100644
--- a/lib/lib-dynamodb/src/commands/ExecuteTransactionCommand.ts
+++ b/lib/lib-dynamodb/src/commands/ExecuteTransactionCommand.ts
@@ -18,7 +18,7 @@ export { DynamoDBDocumentClientCommand, $Command };
 export type ExecuteTransactionCommandInput = Omit<__ExecuteTransactionCommandInput, "TransactStatements"> & {
   TransactStatements:
     | (Omit<ParameterizedStatement, "Parameters"> & {
-        Parameters?: NativeAttributeValue[];
+        Parameters?: NativeAttributeValue[] | undefined;
       })[]
     | undefined;
 };
@@ -27,9 +27,11 @@ export type ExecuteTransactionCommandInput = Omit<__ExecuteTransactionCommandInp
  * @public
  */
 export type ExecuteTransactionCommandOutput = Omit<__ExecuteTransactionCommandOutput, "Responses"> & {
-  Responses?: (Omit<ItemResponse, "Item"> & {
-    Item?: Record<string, NativeAttributeValue>;
-  })[];
+  Responses?:
+    | (Omit<ItemResponse, "Item"> & {
+        Item?: Record<string, NativeAttributeValue> | undefined;
+      })[]
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/GetCommand.ts b/lib/lib-dynamodb/src/commands/GetCommand.ts
index 8f46b914210b..b3edd17328e6 100644
--- a/lib/lib-dynamodb/src/commands/GetCommand.ts
+++ b/lib/lib-dynamodb/src/commands/GetCommand.ts
@@ -23,7 +23,7 @@ export type GetCommandInput = Omit<__GetItemCommandInput, "Key"> & {
  * @public
  */
 export type GetCommandOutput = Omit<__GetItemCommandOutput, "Item"> & {
-  Item?: Record<string, NativeAttributeValue>;
+  Item?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/PutCommand.ts b/lib/lib-dynamodb/src/commands/PutCommand.ts
index 8e345adbb607..1099c1a93585 100644
--- a/lib/lib-dynamodb/src/commands/PutCommand.ts
+++ b/lib/lib-dynamodb/src/commands/PutCommand.ts
@@ -17,24 +17,28 @@ export { DynamoDBDocumentClientCommand, $Command };
  */
 export type PutCommandInput = Omit<__PutItemCommandInput, "Item" | "Expected" | "ExpressionAttributeValues"> & {
   Item: Record<string, NativeAttributeValue> | undefined;
-  Expected?: Record<
-    string,
-    Omit<ExpectedAttributeValue, "Value" | "AttributeValueList"> & {
-      Value?: NativeAttributeValue;
-      AttributeValueList?: NativeAttributeValue[];
-    }
-  >;
-  ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
+  Expected?:
+    | Record<
+        string,
+        Omit<ExpectedAttributeValue, "Value" | "AttributeValueList"> & {
+          Value?: NativeAttributeValue | undefined;
+          AttributeValueList?: NativeAttributeValue[] | undefined;
+        }
+      >
+    | undefined;
+  ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
  * @public
  */
 export type PutCommandOutput = Omit<__PutItemCommandOutput, "Attributes" | "ItemCollectionMetrics"> & {
-  Attributes?: Record<string, NativeAttributeValue>;
-  ItemCollectionMetrics?: Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
-    ItemCollectionKey?: Record<string, NativeAttributeValue>;
-  };
+  Attributes?: Record<string, NativeAttributeValue> | undefined;
+  ItemCollectionMetrics?:
+    | (Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
+        ItemCollectionKey?: Record<string, NativeAttributeValue> | undefined;
+      })
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/QueryCommand.ts b/lib/lib-dynamodb/src/commands/QueryCommand.ts
index 726d6a998b10..c917d55763eb 100644
--- a/lib/lib-dynamodb/src/commands/QueryCommand.ts
+++ b/lib/lib-dynamodb/src/commands/QueryCommand.ts
@@ -19,28 +19,32 @@ export type QueryCommandInput = Omit<
   __QueryCommandInput,
   "KeyConditions" | "QueryFilter" | "ExclusiveStartKey" | "ExpressionAttributeValues"
 > & {
-  KeyConditions?: Record<
-    string,
-    Omit<Condition, "AttributeValueList"> & {
-      AttributeValueList?: NativeAttributeValue[];
-    }
-  >;
-  QueryFilter?: Record<
-    string,
-    Omit<Condition, "AttributeValueList"> & {
-      AttributeValueList?: NativeAttributeValue[];
-    }
-  >;
-  ExclusiveStartKey?: Record<string, NativeAttributeValue>;
-  ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
+  KeyConditions?:
+    | Record<
+        string,
+        Omit<Condition, "AttributeValueList"> & {
+          AttributeValueList?: NativeAttributeValue[] | undefined;
+        }
+      >
+    | undefined;
+  QueryFilter?:
+    | Record<
+        string,
+        Omit<Condition, "AttributeValueList"> & {
+          AttributeValueList?: NativeAttributeValue[] | undefined;
+        }
+      >
+    | undefined;
+  ExclusiveStartKey?: Record<string, NativeAttributeValue> | undefined;
+  ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
  * @public
  */
 export type QueryCommandOutput = Omit<__QueryCommandOutput, "Items" | "LastEvaluatedKey"> & {
-  Items?: Record<string, NativeAttributeValue>[];
-  LastEvaluatedKey?: Record<string, NativeAttributeValue>;
+  Items?: Record<string, NativeAttributeValue>[] | undefined;
+  LastEvaluatedKey?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/ScanCommand.ts b/lib/lib-dynamodb/src/commands/ScanCommand.ts
index ffe1e23829d9..d407bc8b9891 100644
--- a/lib/lib-dynamodb/src/commands/ScanCommand.ts
+++ b/lib/lib-dynamodb/src/commands/ScanCommand.ts
@@ -19,22 +19,24 @@ export type ScanCommandInput = Omit<
   __ScanCommandInput,
   "ScanFilter" | "ExclusiveStartKey" | "ExpressionAttributeValues"
 > & {
-  ScanFilter?: Record<
-    string,
-    Omit<Condition, "AttributeValueList"> & {
-      AttributeValueList?: NativeAttributeValue[];
-    }
-  >;
-  ExclusiveStartKey?: Record<string, NativeAttributeValue>;
-  ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
+  ScanFilter?:
+    | Record<
+        string,
+        Omit<Condition, "AttributeValueList"> & {
+          AttributeValueList?: NativeAttributeValue[] | undefined;
+        }
+      >
+    | undefined;
+  ExclusiveStartKey?: Record<string, NativeAttributeValue> | undefined;
+  ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
  * @public
  */
 export type ScanCommandOutput = Omit<__ScanCommandOutput, "Items" | "LastEvaluatedKey"> & {
-  Items?: Record<string, NativeAttributeValue>[];
-  LastEvaluatedKey?: Record<string, NativeAttributeValue>;
+  Items?: Record<string, NativeAttributeValue>[] | undefined;
+  LastEvaluatedKey?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/TransactGetCommand.ts b/lib/lib-dynamodb/src/commands/TransactGetCommand.ts
index 389739d5626d..ef14b69d9ad8 100644
--- a/lib/lib-dynamodb/src/commands/TransactGetCommand.ts
+++ b/lib/lib-dynamodb/src/commands/TransactGetCommand.ts
@@ -31,9 +31,11 @@ export type TransactGetCommandInput = Omit<__TransactGetItemsCommandInput, "Tran
  * @public
  */
 export type TransactGetCommandOutput = Omit<__TransactGetItemsCommandOutput, "Responses"> & {
-  Responses?: (Omit<ItemResponse, "Item"> & {
-    Item?: Record<string, NativeAttributeValue>;
-  })[];
+  Responses?:
+    | (Omit<ItemResponse, "Item"> & {
+        Item?: Record<string, NativeAttributeValue> | undefined;
+      })[]
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/TransactWriteCommand.ts b/lib/lib-dynamodb/src/commands/TransactWriteCommand.ts
index 79e3cc2af2f2..651b8858d93b 100644
--- a/lib/lib-dynamodb/src/commands/TransactWriteCommand.ts
+++ b/lib/lib-dynamodb/src/commands/TransactWriteCommand.ts
@@ -18,22 +18,30 @@ export { DynamoDBDocumentClientCommand, $Command };
 export type TransactWriteCommandInput = Omit<__TransactWriteItemsCommandInput, "TransactItems"> & {
   TransactItems:
     | (Omit<TransactWriteItem, "ConditionCheck" | "Put" | "Delete" | "Update"> & {
-        ConditionCheck?: Omit<ConditionCheck, "Key" | "ExpressionAttributeValues"> & {
-          Key: Record<string, NativeAttributeValue> | undefined;
-          ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
-        };
-        Put?: Omit<Put, "Item" | "ExpressionAttributeValues"> & {
-          Item: Record<string, NativeAttributeValue> | undefined;
-          ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
-        };
-        Delete?: Omit<Delete, "Key" | "ExpressionAttributeValues"> & {
-          Key: Record<string, NativeAttributeValue> | undefined;
-          ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
-        };
-        Update?: Omit<Update, "Key" | "ExpressionAttributeValues"> & {
-          Key: Record<string, NativeAttributeValue> | undefined;
-          ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
-        };
+        ConditionCheck?:
+          | (Omit<ConditionCheck, "Key" | "ExpressionAttributeValues"> & {
+              Key: Record<string, NativeAttributeValue> | undefined;
+              ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
+            })
+          | undefined;
+        Put?:
+          | (Omit<Put, "Item" | "ExpressionAttributeValues"> & {
+              Item: Record<string, NativeAttributeValue> | undefined;
+              ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
+            })
+          | undefined;
+        Delete?:
+          | (Omit<Delete, "Key" | "ExpressionAttributeValues"> & {
+              Key: Record<string, NativeAttributeValue> | undefined;
+              ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
+            })
+          | undefined;
+        Update?:
+          | (Omit<Update, "Key" | "ExpressionAttributeValues"> & {
+              Key: Record<string, NativeAttributeValue> | undefined;
+              ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
+            })
+          | undefined;
       })[]
     | undefined;
 };
@@ -42,12 +50,14 @@ export type TransactWriteCommandInput = Omit<__TransactWriteItemsCommandInput, "
  * @public
  */
 export type TransactWriteCommandOutput = Omit<__TransactWriteItemsCommandOutput, "ItemCollectionMetrics"> & {
-  ItemCollectionMetrics?: Record<
-    string,
-    (Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
-      ItemCollectionKey?: Record<string, NativeAttributeValue>;
-    })[]
-  >;
+  ItemCollectionMetrics?:
+    | Record<
+        string,
+        (Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
+          ItemCollectionKey?: Record<string, NativeAttributeValue> | undefined;
+        })[]
+      >
+    | undefined;
 };
 
 /**
diff --git a/lib/lib-dynamodb/src/commands/UpdateCommand.ts b/lib/lib-dynamodb/src/commands/UpdateCommand.ts
index 11e3b65be7c4..99a13664364a 100644
--- a/lib/lib-dynamodb/src/commands/UpdateCommand.ts
+++ b/lib/lib-dynamodb/src/commands/UpdateCommand.ts
@@ -20,30 +20,36 @@ export type UpdateCommandInput = Omit<
   "Key" | "AttributeUpdates" | "Expected" | "ExpressionAttributeValues"
 > & {
   Key: Record<string, NativeAttributeValue> | undefined;
-  AttributeUpdates?: Record<
-    string,
-    Omit<AttributeValueUpdate, "Value"> & {
-      Value?: NativeAttributeValue;
-    }
-  >;
-  Expected?: Record<
-    string,
-    Omit<ExpectedAttributeValue, "Value" | "AttributeValueList"> & {
-      Value?: NativeAttributeValue;
-      AttributeValueList?: NativeAttributeValue[];
-    }
-  >;
-  ExpressionAttributeValues?: Record<string, NativeAttributeValue>;
+  AttributeUpdates?:
+    | Record<
+        string,
+        Omit<AttributeValueUpdate, "Value"> & {
+          Value?: NativeAttributeValue | undefined;
+        }
+      >
+    | undefined;
+  Expected?:
+    | Record<
+        string,
+        Omit<ExpectedAttributeValue, "Value" | "AttributeValueList"> & {
+          Value?: NativeAttributeValue | undefined;
+          AttributeValueList?: NativeAttributeValue[] | undefined;
+        }
+      >
+    | undefined;
+  ExpressionAttributeValues?: Record<string, NativeAttributeValue> | undefined;
 };
 
 /**
  * @public
  */
 export type UpdateCommandOutput = Omit<__UpdateItemCommandOutput, "Attributes" | "ItemCollectionMetrics"> & {
-  Attributes?: Record<string, NativeAttributeValue>;
-  ItemCollectionMetrics?: Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
-    ItemCollectionKey?: Record<string, NativeAttributeValue>;
-  };
+  Attributes?: Record<string, NativeAttributeValue> | undefined;
+  ItemCollectionMetrics?:
+    | (Omit<ItemCollectionMetrics, "ItemCollectionKey"> & {
+        ItemCollectionKey?: Record<string, NativeAttributeValue> | undefined;
+      })
+    | undefined;
 };
 
 /**