Issue with ReadResourceAsync() Returning Incorrect Contents in C#

[luisUlg1]

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Your Question

Issue with ReadResourceAsync() Returning Incorrect Contents in C# SDK

Description

I am experiencing an issue when using the ReadResourceAsync() method from the C# SDK to fetch a resource from my MCP server (which is implemented in TypeScript). The response structure seems incorrect compared to what I get when using Python or TypeScript clients.

When calling ReadResourceAsync(), the Contents list returns objects where the uri, text, and mimeType properties contain their own field names instead of the actual values. Below is an example of the response I get in C#:

var result = await mcpClient.ReadResourceAsync("person://properties/alexys");

C# Output contents:

[
  {
    "uri": "uri",
    "mimeType": "mimeType",
    "text": "text"
  }
]

C# Output image:

However, when I fetch the same resource using a Python or TypeScript client, the response is correct and returns the expected data. Below is the correct JSON structure obtained from a different client:

{
  "contents": [
    {
      "uri": "person://properties/alexys",
      "mimeType": "application/json",
      "text": "{\"name\":\"alexys\",\"age\":23,\"height\":1.7}"
    }
  ]
}

I've also verified this behavior using MCP Inspector v0.7.0, which correctly returns data in the same format as the TypeScript and Python clients.

It seems that the C# SDK might not be correctly mapping the JSON response from the server. I would appreciate any insights or suggestions on how to resolve this issue.

Additional Information

• SDK version: 0.1.0-preview.4
• MCP Server implementation: TypeScript
• Steps to reproduce: Call ReadResourceAsync() with a valid resource URI

Has anyone else encountered this issue? Any guidance would be greatly appreciated!