How can I pass user-specific AUTH headers to MCP without recreating the Kernel?

[shlomico-tr]

I have a question about the TOOLS in the Kernel—especially MCP.
Is there a way to define custom headers that can be changed according to the signed-in user?

The only way I’ve found so far is to clone or create a brand-new Kernel, which is inefficient with MCP because it has to reload the tools and that takes time we’d rather save.

In practice, I have an AUTH header that I want to pass—using a different value for each

My code:

// Configure MCP client (with per-user auth header) and add plugin to a dedicated kernel
await using var mcpClient = await McpClientFactory.CreateAsync(
    clientTransport: new SseClientTransport(new()
    {
        Endpoint = new Uri("https://my-mcp-instance.workers.dev/sse"),     // <-- replace with your endpoint
        AdditionalHeaders = new Dictionary
        {
            { "Authorization", $"Bearer {userAuthToken}" }                // <-- user-specific token
        }
    })).ConfigureAwait(false);

// Discover available tools
var tools = await mcpClient.ListToolsAsync().ConfigureAwait(false);
foreach (var tool in tools)
{
    logger.LogInformation($"{tool.Name}: {tool.Description}");
}

// Add plugin functions to the kernel
#pragma warning disable SKEXP0001 // Type is for evaluation purposes only and may change
customKernel.Plugins.AddFromFunctions(
    "CustomPlugin", 
    tools.Select(f => f.AsKernelFunction()));
#pragma warning restore SKEXP0001

// Register the kernel as a keyed service
builder.Services.AddKeyedSingleton("custom", customKernel);

[ShlomiC1234]

Any answer?
Thanks!

[moonbox3]

Adding @markwallace-microsoft to help with the .NET side of things.

[ShlomiC1234]

Updates?