Cactus Hybrid

Cactus shipped Cactus Hybrid, a post-trained build of Google's Gemma 4 E2B that returns a calibrated confidence score with every answer, routing queries to a larger model when confidence falls below 0…

Google's Gemma 4 model uses a 68k-parameter probe layer that predicts decoding errors by reading hidden states, achieving a 0.79-0.88 AUROC on audio benchmarks despite being trained on zero audio data…