Cursor disconnects after a few minutes

[dansiegel]

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Discussion Topic

Not sure if I'm doing something wrong or maybe there is a bug in the latest preview. I have an MCP I built to help my development with Copilot or Cursor. It works to a degree but I'm noticing after a few minutes (~4-5 minutes) it seems to start giving me errors with the following console output:

025-12-11 14:52:35.596 [info] Found 8 tools, 0 prompts, and 0 resources
2025-12-11 14:52:36.950 [info] No stored tokens found
2025-12-11 14:52:37.080 [info] No stored tokens found
2025-12-11 14:52:37.085 [error] Client error for command Streamable HTTP error: Failed to open SSE stream: Bad Request
2025-12-11 14:52:37.085 [error] Client error for command Failed to reconnect SSE stream: Streamable HTTP error: Failed to open SSE stream: Bad Request
2025-12-11 14:52:37.085 [error] Client error for command Maximum reconnection attempts (2) exceeded.
2025-12-11 15:11:10.861 [info] No stored tokens found
2025-12-11 15:24:35.778 [info] No stored tokens found

builder.Services.AddMcpServer(o =>
    {
        o.ServerInfo = new Implementation
        {
            // my server info
        };
    
    })
    .WithHttpTransport(opts =>
    {
        // Have tried adding these but it hasn't made a difference
        opts.IdleTimeout = Timeout.InfiniteTimeSpan;
        opts.MaxIdleSessionCount = 50_000;
        opts.Stateless = true;
    })
    .WithToolsFromAssembly();
var app = builder.Build();
app.MapMcp();

Note that I have built the MCP as a Docker Container and am running it with Docker

FROM mcr.microsoft.com/dotnet/aspnet:10.0 AS final
WORKDIR /app
# Expose HTTP port for MCP server
EXPOSE 8080
ENV ASPNETCORE_URLS=http://+:8080
# Keep diagnostics off for smaller footprint.
ENV DOTNET_EnableDiagnostics=0
COPY --from=build /app/publish .
ENTRYPOINT ["dotnet", "MyMcp.dll"]

[PederHP]

Try setting up a regular ping. Some client hosts aggressively disconnect servers that don't keep the connection alive.