Overview

Amazon has launched an official, pre‑built SDK for the Selling Partner API (SP‑API) that targets C# and .NET developers. Distributed as a NuGet package, the library eliminates the manual step of generating client code from Amazon’s OpenAPI definitions, a process that previously consumed many hours of development and ongoing upkeep. Sellers and their technical partners should pay attention because the SDK promises quicker time‑to‑market, automatic alignment with Amazon’s API revisions, and built‑in handling of OAuth authentication.

Key Points

• One‑command install — Adding the software.amzn.spapi package to any .NET 7.0 or later project requires a single dotnet add package call, replacing the multi‑hour workflow of downloading specs and running code generators.
• Automatic API updates — Amazon publishes SDK updates centrally; when a developer bumps the NuGet version, the latest SP‑API changes are incorporated without re‑running generation scripts.
• Built‑in OAuth flow — Fluent builder methods accept client ID, client secret and refresh token, allowing the SDK to obtain and refresh access tokens automatically, removing the need for custom signing code.
• Comprehensive endpoint coverage – Core SP‑API sections such as Orders, Catalog Items, Feeds, Listings and many ancillary services are exposed through strongly‑typed C# methods, enabling a single line call for most operations.
• Modern .NET design — The library follows current C# patterns, offering async methods, dependency‑injection‑ready interfaces and builder‑style configuration, which fits naturally into existing .NET architectures.

How the Prebuilt SP‑API SDK Works

1. Add the package — Execute dotnet add package software.amzn.spapi in the solution directory; the NuGet manager retrieves the compiled client library together with all required dependencies.
2. Configure credentials — Instantiate the builder and supply the three OAuth pieces:

   var spApiClient = new SpApiClientBuilder()
       .WithClientId("YOUR_CLIENT_ID")
       .WithClientSecret("YOUR_CLIENT_SECRET")
       .WithRefreshToken("YOUR_REFRESH_TOKEN")
       .Build();
   

   The builder stores these values, requests an access token from Amazon, and refreshes it automatically when it expires.