A Nature Chemical Biology study showed that intracellular delivery of multivalent binding agents using intrinsically disordered regions (IDRs) promotes condensate formation that enhances CAR‑T cytotoxicity against low‑antigen tumors. The work provides a mechanistic route to increase synapse stability and signalling in T cells targeting scarce tumor antigens, potentially widening CAR‑T applicability beyond high‑antigen hematologic malignancies. Translational paths include optimizing IDR constructs for safety and persistence, and integrating the strategy into existing CAR platforms for solid tumors where antigen density limits efficacy.