Oct 5, 2026
Multi-CaMeL preserves trust boundaries between agents, with utility costs
Researchers show that a hierarchical system can be compromised even when its individual agents use CaMeL, because downstream agents can reinterpret untrusted data as trusted instructions. Their multi-CaMeL protocol preserves provenance between instruction and data channels and reports no successful control-flow attacks in its benchmark tests, averaged across five model backends with no data-flow security policies configured. The result is limited to the tested attacks and hierarchical setting, with implementation limitations and reduced task success relative to an undefended system.