Microsoft Releases 5-Package .NET SDK for AG-UI, Extending Agent Protocol to C#
Updated
Updated · InfoWorld · Sep 27
Microsoft Releases 5-Package .NET SDK for AG-UI, Extending Agent Protocol to C#
3 articles · Updated · InfoWorld · Sep 27
Summary
Microsoft on Sept. 25 published a .NET SDK for AG-UI on NuGet under the MIT license, giving C# developers native support for the agent-user interaction protocol.
The SDK standardizes how AI agents connect to front-end apps through an event-based model, with eight event categories covering run life cycles, text streaming, tool calls, state sync, activity, subagents, special functions and draft events.
Its C# implementation works both ways: AGUI.Server exposes an agent as an AG-UI endpoint, while AGUI.Client lets .NET applications consume AG-UI endpoints over HTTP.
The release ships as five NuGet packages and already underpins AG-UI support in Microsoft Agent Framework, which Microsoft said is now based on the new .NET SDK.
Built with CopilotKit and housed alongside TypeScript and Python SDKs in the AG-UI repository, the launch broadens cross-language support for a protocol meant to unify agent-to-application communication.