Método Configure(IApplicationBiulder app, IWebHostEnvironment env)

Startup.cs

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
  app.UseRouting();
  app.UseEndpoints(endpoints =>
  {
    endpoints.MapGrpcService<OperacionService>();
    endpoints.MapGet("/", async context =>
    {
      await context.Response.WriteAsync("Communication with gRPC endpoints must be made through a gRPC client. To learn how to create a client, visit: https://go.microsoft.com/fwlink/?linkid=2086909");
    });
  });
}