The TCP stack, by design, hides much of the information about it's functioning and performance from userland. As such, unearthing the root cause of performance problems can be both frustrating and time consuming. While some instrumentation is available through the current TCP_INFO struct a more extensive set of instruments may provide better data for TCP diagnostics and performance monitoring. This BoF intends to bring together interested parties and stakeholders in order to discuss the need and requirements for extending the current set of TCP instruments. The discussion will include potential instruments, use case scenarios, access methods, metric validation, and other issues.