A harness that keeps lessons between attempts turned a general reasoner into a robot policy with 63.9% success
AspireAI community · arXiv
Multimodal foundation models reason well but translate that into physical action poorly, and this work starts from an unusual observation: across real-world manipulation experiments, ChatGPT-6-Astra already functions as a physically actionable, context-responsive policy. LEXP is a harness for learning from physical experience through context-space adaptation, combining task-level planning with an experience module that interprets execution evidence, extracts lessons together with their applicability conditions, and reuses them as contextual feedback for later actions. Model weights and the action interface stay fixed throughout. Across 12 real-world manipulation tasks LEXP achieved 23 of 36 successful trials (63.9%) against 19 of 36 (52.8%) with memory alone and 2 of 36 (5.6%) for vanilla Astra. Ablations on three tasks showed that removing planning dropped success from 7 of 9 to 4 of 9, and removing retained experience dropped it to 3 of 9, with execution traces showing feedback-guided corrections and cross-episode reuse of an inspection strategy. The trials are small in number, and the harness depends on a frontier model being available to drive the robot.
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