---

license: mit task_categories:

• text-generation configs:
• config_name: default data_files:
  • split: train path: data/train.parquet tags:
• terminal
• rl
• code

---

LiteCoder-Terminal-RL-preview

Paper | Code | Blog Post

This dataset contains 602 standardized Harbor terminal environments and was released as part of the paper LiteCoder-Terminal: Scaling Long-Horizon Terminal Environments for Learning Language Agents.

Unlike static text-only instructions, these environments are fully executable and are designed to support the training of terminal-based agents.

Environment Generation Pipeline

The lack of high-quality, executable training environments is currently a major challenge for training terminal agents. Raw task descriptions lack the execution feedback required for techniques like rejection sampling and reinforcement learning, so an executable environment is essential. We implemented a five-stage synthesis pipeline to convert sampled tasks into the Harbor format using the Claude Agent SDK:

1. Task refinement: rewrite raw task descriptions into clear and testable instructions
2. Environment setup: prepare the execution environment and required resources
3. Reference solution generation: produce a working solution for the task
4. Verifier creation: construct test cases and evaluation logic
5. Harbor packaging: assemble everything into the standard Harbor format

Environment Structure

Each environment represents a standardized terminal task instance organized in the Harbor format, which is as the following:

├── instruction.md
├── task.toml
├── environment
│   ├── Dockerfile
│   └── ...
├── solution
│   ├── solve.sh
│   └── ...
└── tests
    ├── test.sh
    └── ...

Citation

@article{peng2026litecoderterminal,
  title={LiteCoder-Terminal: Scaling Long-Horizon Terminal Environments for Learning Language Agents},
  author={Peng, Xiaoxuan and Zhang, Kaiqi and Lu, Xinyu and Cao, Boxi and Lu, Yaojie and Lin, Hongyu and Han, Xianpei and Sun, Le},
  journal={arXiv preprint arXiv:2605.29559},
  year={2026}
}