AlphaBrainGroup/alphabrain-rlt-5traj-alltasks-libero-goal
AlphaBrain-RLT (5-trajectory · LIBERO-Goal · all 10 tasks)
RL-Token (RLT) fine-tuning release from the AlphaBrain framework. Lightweight Actor–Critic on top of a frozen VLA backbone, covering all 10 LIBERO-Goal tasks in the low-data (5 trajectories / task) setting.
RL-Token compresses the frozen VLA's hidden state through an information bottleneck encoder, then trains an Actor head (residual action edits) and a Critic head (state value) with off-policy reinforcement learning. The VLA backbone — `AlphaBrainGroup/qwenoft-5traj-libero-goal` — is frozen during RL, so only a few hundred MB of parameters are learned on top.
Overview
Results
Evaluated with 50 episodes per task across all 10 LIBERO-Goal tasks (eval release 2026-04-16):
Numbers are from our internal release eval; per-run variance is a few percentage points. Reproduction numbers higher or lower than reported are expected — please file an issue / PR with details.
Files
├── README.md model card
├── metrics.json RL training metrics trace
├── eval_summary.json per-task SR + overall (2026-04-16 release)
└── rl_offpolicy_iter_00400/
├── actor.pt Actor (~1.8 MB)
├── critic.pt Critic (~3.3 MB)
└── encoder.pt Bottleneck encoder (~517 MB)Usage
This checkpoint is evaluated via a custom RL eval pipeline. Clone the AlphaBrain framework and download both the base VLA and this RLT release:
git clone https://github.com/AlphaBrainGroup/AlphaBrain.git
cd VLA-Engine-Developer
pip install -e .
export PRETRAINED_MODELS_DIR=/path/to/models
export LIBERO_PYTHON=/path/to/envs/libero/bin/python # env with robosuite
export LIBERO_HOME=/path/to/LIBERO
# Download base VLA
huggingface-cli download AlphaBrainGroup/qwenoft-5traj-libero-goal \
--local-dir results/training/QwenOFT-5traj-libero_goal/final_model
# Download RLT release
huggingface-cli download AlphaBrainGroup/alphabrain-rlt-5traj-alltasks-libero-goal \
--local-dir results/rlt_training_TD3/rlt_5traj_alltasks_release/rl_offpolicy/checkpoints
# Run the 10-task LIBERO-Goal evaluation (splits across 3 GPUs)
bash scripts/run_rl_scripts/run_eval_rlt.sh \
results/rlt_training_TD3/rlt_5traj_alltasks_release/rl_offpolicy \
0,1,2The eval script:
- Loads the base VLA + Actor / Critic / Encoder
- Splits the 10 LIBERO-Goal tasks across the 3 GPUs you specify
- Rolls out 50 episodes per task
- Writes per-shard JSONs and an aggregated
summary.json
Reproduction
Training is two-phase — (1) supervised VLA fine-tuning on 5 trajectories per task, (2) RL-Token Actor–Critic fine-tuning with a frozen VLA. The full pipeline can be reproduced with:
bash scripts/run_rl_scripts/run_rlt_5traj_alltasks.shSee the RL scripts in the framework for details, required env variables, and per-phase configuration.
License
MIT — see the parent repository.
Citation
@misc{alphabrain2026,
title = {AlphaBrain: A Modular Open-Source Framework for Embodied Intelligence Research},
author = {AlphaBrain Team},
year = {2026},
url = {https://github.com/AlphaBrainGroup/AlphaBrain}
}