# McpServerEndpointAnnotation Properties

- Package: [Aspire.Hosting](/reference/api/csharp/aspire.hosting.md)
- Type: [McpServerEndpointAnnotation](/reference/api/csharp/aspire.hosting/mcpserverendpointannotation.md)
- Kind: `Properties`
- Members: `1`

Represents an annotation that identifies an endpoint on a resource that hosts a Model Context Protocol (MCP) server.

## EndpointUrlResolver

- Name: `EndpointUrlResolver`
- Modifiers: `get`
- Returns: `Func<IResourceWithEndpoints, CancellationToken, Task<Uri?>>`
- Source: [GitHub](https://github.com/microsoft/aspire/blob/bd20f904cde09ecb9c9ae5116a6f13614bf2d7c2/src/Aspire.Hosting/ApplicationModel/McpServerEndpointAnnotation.cs#L28)

Gets the callback that resolves the MCP server endpoint URL from the resource.

```csharp
public Func<IResourceWithEndpoints, CancellationToken, Task<Uri?>> EndpointUrlResolver { get; }
```