LocAgent: Graph-Guided LLM Agents for Code Localization
Authors: name: Zhaoling Chen, name: Xiangru Tang, name: Gangda Deng, name: Fang Wu, name: Jialong Wu, name: Zhiwei Jiang, name: Viktor Prasanna, name: Arman Cohan, name: Xingyao Wang

Code localization--identifying precisely where in a codebase changes need to
be made--is a fundamental yet challenging task in software maintenance.
Existing approaches struggle to efficiently navigate complex codebases when
identifying relevant code sections. The challenge lies in bridging natural
language problem descriptions with the appropriate code elements, often
requiring reasoning across hierarchical structures and multiple dependencies.
We introduce LocAgent, a framework that addresses code localization through
graph-based representation. By parsing codebases into directed heterogeneous
graphs, LocAgent creates a lightweight representation that captures code
structures (files, classes, functions) and their dependencies (imports,
invocations, inheritance), enabling LLM agents to effectively search and locate
relevant entities through powerful multi-hop reasoning. Experimental results on
real-world benchmarks demonstrate that our approach significantly enhances
accuracy in code localization. Notably, our method with the fine-tuned
Qwen-2.5-Coder-Instruct-32B model achieves comparable results to SOTA
proprietary models at greatly reduced cost (approximately 86% reduction),
reaching up to 92.7% accuracy on file-level localization while improving
downstream GitHub issue resolution success rates by 12% for multiple attempts
(Pass@10). Our code is available at https://github.com/gersteinlab/LocAgent.