FastHarness cut agentic robot reviewer token use 57.2% and raised manipulation success from 80% to 97.19% without retraining the policy
AspireAI community · arXiv
Robot agent systems that ask a language model to supervise every action chunk pay for that review on every step, even in situations the robot has handled before. FastHarness schedules that supervision adaptively: a fast path uses stage memory and reviewed outcomes to review less often as experience accumulates, while a recovery path concentrates supervision on correcting errors, and failure experience is retained to guide later interventions. Across four simulated manipulation tasks, reviewer token use fell an average of 57.2% per task from the first evaluated episode to the mean of the final five, mean episode time dropped from 85.5 to 52.0 minutes, and mean success rose from 80% for the plain GPT-as-Policy baseline to 97.19% with FastHarness. The policy stays frozen and acts on current observations, so no additional model training is needed. The limitation is that these are simulation results on four tasks with GPT-6 Astra supervising a pi0.5 policy, not physical robot deployments.
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