v0.1.0-preview.3

This release overhauls the resource system, refactors transports for graceful shutdown, introduces prompt support with McpServerPrompt and McpClientPrompt, and adds progress reporting and annotation support.

Breaking Changes

Refer to the C# SDK Versioning documentation for details on versioning and breaking change policies.

1. Add ToolAnnotations support #124
   • McpServerToolAttribute constructor no longer accepts a positional string; must use Name = "..." instead
2. Overhaul of Resources #125
   • ResourceContents changed to an abstract class; Text and Blob properties removed
   • Must use TextResourceContents or BlobResourceContents subclasses instead
3. Add [McpServerPrompt] support #126
   • ListPromptsAsync return type changed
   • GetPromptAsync parameter type changed
   • IMcpServerBuilder namespace moved
   • All With*Handler extension methods deleted
4. Add missing Annotations #138
   • Annotated abstract record base class deleted
   • Annotations property inlined into Content, Resource, and ResourceTemplate
5. Refactor transports to help enable graceful shutdown #142
   • McpServerHostedService deleted
   • IClientTransport.ConnectAsync now returns ITransport instead of the previous type
   • StartAsync replaced by RunAsync
6. Improve progress reporting #145
   • OperationNames class deleted; replaced by RequestMethods

What's Changed

• Fix some issues with Native AOT #130 by @stephentoub
• Add ToolAnnotations support #124 by @stephentoub
• Add missing Annotations #138 by @stephentoub
• Remove Assembly.GetCallingAssembly #133 by @stephentoub
• Refactor transports to help enable graceful shutdown #142 by @halter73 (co-authored by @stephentoub)
• Overhaul of Resources #125 by @aaronpowell (co-authored by @stephentoub @PederHP)
• Fix binding to wrong overload in WithTools #152 by @stephentoub
• Improve progress reporting #145 by @stephentoub
• Add [McpServerPrompt] support #126 by @stephentoub
• Implement cancellation notifications #146 by @stephentoub

Documentation Updates

• Fix sample in README #136 by @BrennanConroy

Repository Infrastructure Updates

• Bump version to 0.1.0-preview.3 #162 by @jeffhandley

Acknowledgements

• @BrennanConroy made their first contribution in #136
• @stvansolano reviewed pull requests

Full Changelog: v0.1.0-preview.2...v0.1.0-preview.3