$tX$ and $t\bar{t}$X and their EFT interpretation in ATLAS and CMS

This contribution reports the most recent results on tX and $t\bar{t}$X production from the ATLAS and CMS collaborations, including the $t\bar{t}t\bar{t}$ observation from CMS and the first differential cross-section for $t\bar{t}W$ production from ATLAS. The sensitivity of t($\bar{t}$)X measurements to the top-quark/boson coupling can be exploited to search for the presence of new physics with an effective field theory approach. The latest results from CMS in this sector will also be presented, showing no tensions with the SM expectations. The presented results are obtained using proton-proton collision performed at the LHC at $\sqrt{s}=13$ TeV.