- This removes the requirement to configure data protection which is the motivating reason for this change
- This means that McpServer.ClientInfo will always be null in stateless mode
* Decouple Handlers and Collections (e.g. ToolsHandler and ToolsCollection) from Capabilities by promoting them to the options types.
Also, group all handlers in container classes, for server, I decided to move McpServerHandlers down to Mcp.Core and move the NotificationHandlers there too.
Also, Fix ListResourceTemplatesHandler issue.
* Add remarks for empty protocol capability types
* Keep JsonIgnore properties and mark them as Obsolete
* Continue supporting Obsolete members
* Update Obsolete messages to indicate the member will be removed
* Add EditorBrowsable Never to the remaining obsolete members
* Update content according to latest spec
* Add Title to a bunch of types
* Add _meta to lots of types
* Address feedback, more cleanup, fix NAOT test failure
- It allows a single MCP session spanning multiple requests
to be handled by different servers without sharing state
- It does require the servers share data protection keys, but this
is standard for ASP.NET Core cookies and antiforgery as well
- It immediately throws for unsupported operations like sampling
* Add McpServer/ClientResource{Template} and friends
This PR copies the same design used by tools and prompts to add McpServerResource, McpServerResourceAttribute, McpServerResourceTypeAttribute, McpClientResource, and then all of those for ResourceTemplate as well.
Unlike the others, [McpServerResource] is permitted not only on methods but also on properties. This convenience is afforded because such resources aren't parameterized, and thus can be easily modeled as properties, likely auto-props, e.g.
```C#
[McpServerResource]
public static BlobResourceContents MyAmazingData { get; } = Create();
```
Details about resources can be encoded into the attributes or provided via McpServerResource{Template}.Create methods. If not URI is explicitly defined, one is derived from the member name and arguments. For templates, this means manufacturing a URI template that includes variables for all non-DI parameters.
This also fixes a few issues discovered along the way:
- McpClientExtensions are updated to use `ValueTask<T>` instead of `Task<T>` where relevant.
- McpServerPrompt was missing handling for progress notifications; that's been rectified. It was also missing configuring the description on the ProtocolPrompt.
- Renamed IMcpServerPrimitive.Name to Id. For resources, names aren't unique.
- After going back and forth, updated McpServer to not fail for missing handlers and to instead register default handlers. It simplifies the implementation and makes it more consistent.
- Added a bunch of primitive types into the McpJsonUtilities JSON source generator context so that such primitives are usable with tools/prompts/resources without folks being required to add them into their own context for Native AOT. I think we should consider pushing this down to AIJsonUtilities, instead, and that will then flow up to McpJsonUtilities automatically.
* Address feedback
