From Laboratory to Real-World Applications: Benchmarking Agentic Code Reasoning at the Repository Level

Jia Li, Yuxin Su, Michael R. Lyu


Abstract
As large language models (LLMs) evolve into autonomous agents, evaluating repository-level reasoning, the ability to maintain logical consistency across massive, real-world, interdependent file systems, has become critical. Current benchmarks typically fluctuate between isolated code snippets and black-box evaluations. We present RepoReason, a white-box diagnostic benchmark centered on abductive assertion verification. To eliminate memorization while preserving authentic logical depth, we implement an execution-driven mutation framework that utilizes the environment as a semantic oracle to regenerate ground-truth states. Furthermore, we establish a fine-grained diagnostic system using dynamic program slicing, quantifying reasoning via three orthogonal metrics: ESV (reading load), MCL (simulation depth), and DFI (integration width). Comprehensive evaluations of frontier models (e.g., Claude-4.5-Sonnet, DeepSeek-v3.1-Terminus) reveal a prevalent aggregation deficit, where integration width serves as the primary cognitive bottleneck. Our findings provide granular white-box insights for optimizing the next generation of agentic software engineering.
Anthology ID:
2026.acl-long.399
Volume:
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Month:
July
Year:
2026
Address:
San Diego, California, United States
Editors:
Maria Liakata, Viviane P. Moreira, Jiajun Zhang, David Jurgens
Venue:
ACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
8845–8869
Language:
URL:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.399/
DOI:
Bibkey:
Cite (ACL):
Jia Li, Yuxin Su, and Michael R. Lyu. 2026. From Laboratory to Real-World Applications: Benchmarking Agentic Code Reasoning at the Repository Level. In Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers), pages 8845–8869, San Diego, California, United States. Association for Computational Linguistics.
Cite (Informal):
From Laboratory to Real-World Applications: Benchmarking Agentic Code Reasoning at the Repository Level (Li et al., ACL 2026)
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PDF:
https://preview.aclanthology.org/ingest-acl/2026.acl-long.399.pdf
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 2026.acl-long.399.checklist.pdf