Portable Computer keeps its model on-device and sandboxes approved actions

Perplexity says Portable Computer keeps its model and harness on-device. Approved actions run in an OS sandbox that restricts access to processes, files and networks; if the sandbox is unavailable, tools don’t run. The company reports an 82.6% score for its harness with an on-device 27B model and 85.4% for its post-trained PPLX 27B. For Comet and Computer, it also says BrowseSafe screens retrieved content for prompt injection, sensitive actions require confirmation, and Trail of Bits audited those defenses.