AWS SDK for .NET Documentation
ClientToken Property
AmazonAmazon.EC2.ModelCreateReservedInstancesListingRequestClientToken Did this page help you?   Yes   No    Tell us about it...
A unique, case-sensitive identifier you provide to ensure idempotency of your listings.
Declaration Syntax
C#
public string ClientToken { get; set; }
Remarks
This helps avoid duplicate listings. For more information, see 'Ensuring Idempotency' in the Amazon Elastic Compute Cloud User Guide.

Assembly: AWSSDK (Module: AWSSDK) Version: 1.5.60.0 (1.5.60.0)