C#: McpServer.Create

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Track the options before McpServer.Create

using AgentCat;
using ModelContextProtocol.Protocol;
using ModelContextProtocol.Server;

var options = new McpServerOptions
{
    ServerInfo = new Implementation { Name = "echo-mcp", Version = "1.0.0" },
    ToolCollection = [McpServerTool.Create((string message) => $"Echo: {message}", new() { Name = "echo" })],
};

// Track the options BEFORE McpServer.Create
AgentCatSdk.Track(options, "proj_YOUR_PROJECT_ID", new AgentCatOptions
{
    EnableAgentTracking = true,
});

await using (var server = McpServer.Create(new StdioServerTransport("echo-mcp"), options))
{
    await server.RunAsync();
}

• Before McpServer.Create. The server reads the filters of its options when it is created, so a Track() call after McpServer.Create does not reach that server.
• The project ID. null reads it from the AGENTCAT_PROJECT_ID environment variable. An empty string, or no project ID at all, tracks the server but sends no events to AgentCat: your exporters still get them.
• Options. The third argument is an AgentCatOptions object with the same properties as for WithAgentCat(). AgentCat reads it once, during the call: later changes have no effect.
• It never throws. Track() returns the same McpServerOptions. When AgentCat cannot track the server, it returns them unchanged and the server runs untracked.
• Tracking again changes nothing. A second Track() on the same options installs nothing, and the first call’s project ID and options stay.

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Custom events

using System.Text.Json.Nodes;
using AgentCat;
using ModelContextProtocol.Server;

var upgrade = McpServerTool.Create(
    async (McpServer server, string plan) =>
    {
        await AgentCatSdk.PublishCustomEventAsync(server, "proj_YOUR_PROJECT_ID", new CustomEventData
        {
            ResourceName = "subscription_upgraded",
            Parameters = new JsonObject { ["plan"] = plan },
        });

        return $"Upgraded to {plan}";
    },
    new() { Name = "upgrade", Description = "Upgrades the subscription." });

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Shutdown

• Allow 6 seconds. Set the grace period of your container above the time that your server needs to stop, plus 6 seconds.
• The signal handlers never cancel the signal, so the process ends with its usual exit code. They do nothing when a .NET host in the same process cancelled the signal first.
• To wait for the events in your own code, call await AgentCatSdk.FlushAsync(TimeSpan.FromSeconds(5)). It returns true when nothing is left to send. AgentCatSdk.ShutdownAsync() also closes the queue: call it once, when your own code ends the process.
• DisableShutdownHandlers = true on the first install of the process turns these handlers off. Then call FlushAsync or ShutdownAsync before the process ends, or the queued events are lost.