EdgeGen improves tool-calling AI agents with harder test tasks

EDGEGEN: Improving Tool-Calling Agents Beyond Happy Paths with Synthetic Edge Case Generation

Artificial Intelligence

Summary

Tool-calling AI agents help automate tasks but often are only tested on easy, common examples. The authors created EdgeGen, a system that automatically makes tricky test tasks by finding rules the AI should follow and generating examples that break those rules. This helps find weak spots and improves the AI when it trains on these harder examples. EdgeGen works without needing humans to label data and showed better improvements than other methods on airline-related tasks.

What this means in practice

Authors

Harshavardhan Abichandani, Penny Chong, Jiyuan Shen, Gunraj Singh, Ashutosh Hathidara, Marcus Duigan Xing Yu, Jane Lo, Atin Ghosh, Yipeng Li, Daniel Dahlmeier

Abstract

Tool-calling LLM agents are increasingly deployed in enterprise applications. However, effective evaluation and optimization require high-quality, diverse task datasets that are often difficult to obtain due to privacy and other constraints. Existing synthetic task generation methods often produce generic tasks that ignore an agent's underlying state or database and fail to reflect real-world usage diversity. We propose EdgeGen, a synthetic task generation framework that extracts compliance rules from an agent's specification and uses them to generate database-grounded edge-case tasks designed to violate these rules. When combined with existing synthetic data generation techniques, EdgeGen enables agent improvement through finetuning and harness optimization. The resulting pipeline forms a fully automated closed-loop system that requires no human annotation. Finetuning on data generated by EdgeGen yields a consistent mean progress improvement of 2 percent to 42 percent on tau2bench airline domain, while other baseline methods show degradation for some models. On the other hand, for harness optimization, our method shows a mean progress improvement of 10 percent and 30 percent over the human-curated and base harnesses, respectively, for the Gemma-4-e4b model.