EnvScaler: Scaling Tool-Interactive Environments for LLM Agent via Programmatic Synthesis
Xiaoshuai Song, Haofei Chang, Guanting Dong, Yutao Zhu, Ji-Rong Wen, Zhicheng Dou
Abstract
Large language models (LLMs) are expected to be trained to act as agents in various real-world environments, but this process relies on rich and varied tool-interaction sandboxes. However, access to real systems is often restricted; LLM-simulated environments are prone to hallucinations and inconsistencies; and manually built sandboxes are hard to scale. In this paper, we propose EnvScaler, an automated framework for scalable tool-interaction environments via programmatic synthesis. EnvScaler comprises two components. First, SkelBuilder constructs diverse environment skeletons through topic mining, logic modeling, and quality evaluation. Then, ScenGenerator generates multiple task scenarios and rule-based trajectory validation functions for each environment. With EnvScaler, we synthesize 191 environments and about 7K scenarios, and apply them to Supervised Fine-Tuning (SFT) and Reinforcement Learning (RL) for Qwen3 series models. Results on three benchmarks show that EnvScaler significantly improves LLMs’ ability to solve tasks in complex environments involving multi-turn, multi-tool interactions.- Anthology ID:
- 2026.findings-acl.407
- Volume:
- Findings of the Association for Computational Linguistics: ACL 2026
- Month:
- July
- Year:
- 2026
- Address:
- San Diego, California, United States
- Editors:
- Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
- Venue:
- Findings
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 8326–8357
- Language:
- URL:
- https://preview.aclanthology.org/ingest-acl/2026.findings-acl.407/
- DOI:
- Cite (ACL):
- Xiaoshuai Song, Haofei Chang, Guanting Dong, Yutao Zhu, Ji-Rong Wen, and Zhicheng Dou. 2026. EnvScaler: Scaling Tool-Interactive Environments for LLM Agent via Programmatic Synthesis. In Findings of the Association for Computational Linguistics: ACL 2026, pages 8326–8357, San Diego, California, United States. Association for Computational Linguistics.
- Cite (Informal):
- EnvScaler: Scaling Tool-Interactive Environments for LLM Agent via Programmatic Synthesis (Song et al., Findings 2026)
- PDF:
- https://preview.aclanthology.org/ingest-acl/2026.findings-acl.407.pdf