Qwen2.5-3B-Instruct student trained with SACD (State-Aware Correction Distillation), a per-turn, signal-gated on-policy distillation method, from the langfeng01/GiGPO-Qwen2.5-7B-Instruct-ALFWorld teacher. This is the step-250 checkpoint.

Label-only / DAgger-style on-policy distillation on top of OPD. Each turn the student samples and always drives the environment (trajectory stays on-policy). Per turn a disagreement detector δ (here the k1 log-prob gap log π_S − log π_T) is computed; when δ > τ that turn's loss switches to SFT on a teacher-decoded counterfactual label (the teacher never touches the env), otherwise it stays standard reverse-KL OPD. The trigger self-anneals as the student approaches the teacher.