Machine Heart

Oct 26, 2026 · Artificial Intelligence

27B AREX-2 Beats 1.6T Models: Long-Horizon Reflection Unlocks Trainable RSI Path

The AREX-2 model, a 27B parameter model trained with long-horizon reflection on machine learning and algorithmic programming tasks, outperforms much larger models on benchmarks like MLE-bench and BrowseComp, demonstrating that reflective self-improvement can transfer across domains and provide a verifiable path to recursive self-improvement (RSI).