๐ค AI Summary
This study investigates whether internal representations of a learned decision-making system encode interpretable concepts that explain its behavior. In the Game of Hidden Rulesโa setting without explicit rule labelsโthe authors train a tokenized autoregressive Transformer agent and, for the first time, apply sparse autoencoders (SAEs) to extract structured features from its decision embeddings. The results demonstrate that individual SAE activation dimensions selectively correspond to fundamental concepts such as shapes and buckets, accounting for the vast majority of relevant decisions. Moreover, these representations reveal interpretable exploratory actions and feedback-driven strategies for switching between hidden rules, offering novel evidence for the interpretability of unsupervised rule-inference agents.
๐ Abstract
A central challenge in interpreting learned decision-making systems is to determine whether their internal representations contain concepts that help explain their behavior. We report interpretability experiments for a tokenized autoregressive Transformer agent in the Game of Hidden Rules (GOHR). We focus on a compact two-rule task in which both hidden rules map object shapes to target buckets, but with different permutations. The policy is trained on episodes sampled from these two hidden rules and then evaluated with fixed weights. It is never given a rule label and does not use an explicit rule classifier; any rule information must be inferred implicitly from interaction history. In this setting, the correct rule is not identifiable before the agent tries an informative move and observes accept/reject feedback. Sparse autoencoders (SAEs) trained on the agent's decision-token embeddings recover this structure. When held-out decisions are labeled by simple concepts such as the chosen shape or bucket, SAE dimensions that are highly selective for a concept cover most decisions where that concept is present. Individual SAE dimensions also correspond to interpretable strategies such as probing one rule hypothesis and switching after negative feedback.