Why Are AI Agent–Involved Pull Requests (Fix-Related) Remain Unmerged? An Empirical Study
Open accessAbstract
Autonomous coding agents (e.g., OpenAI Codex, Devin, GitHub Copilot) are increasingly used to generate fix-related pull requests (PRs) in real-world software repositories. However, their practical effectiveness depends on whether project maintainers accept and merge these contributions. In this paper, we present an empirical study of AI agent–involved fix-related PRs, examining both their integration outcomes, latency, and the factors that hinder successful merging. We first analyze 8,106 fix-related PRs authored by five widely used AI coding agents from the AIDEV-POP dataset to quantify the proportions of PRs that are merged, closed without merging, or remain open. We then conduct a manual analysis of a statistically significant sample of 326 closed but unmerged PRs, spending approximately 100 person-hours to construct a structured catalog of 12 failure reasons. Our results indicate that test case failures and prior resolution of the same issues by other PRs are the most common causes of non-integration, whereas build or deployment failures are comparatively rare. Overall, our findings expose key limitations of current AI coding agents in real-world settings and highlight directions for their further improvement and for more effective human-AI collaboration in software maintenance.
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Research works printed but not linked: 1
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Cited by
Still being checked.
- Authors
- Alam, K., Mondal, S., & Roy, B.
- Affiliations
- University of Saskatchewan (CA)
- Venue
- Proceedings of the 23rd International Conference on Mining Software Repositories
- Publisher
- ACM
- Published
- 2026-04-13
- Pages
- 964-968
- OpenAlex
- W7171968711
- Cited by
- 0
- References
- 21
- FWCI
- 0.00
- Type
- conference paper
- Open access
- hybrid
- doi.org
- Locations
- International Conference on Mining Software Repositories (MSR) (publishedVersion, cc-by)
- Funders
- This research is supported in part by the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grants program, and by the industry-stream NSERC CREATE in Software Analytics Research (SOAR). (410521)
- Topics
- Physical Sciences › Computer Science › Information Systems › Software Engineering Research
- Physical Sciences › Computer Science › Information Systems › Software Engineering Techniques and Practices
- Physical Sciences › Computer Science › Computer Science Applications › Open Source Software Innovations
- Keywords
- coding agents, autonomous coding agents, human-AI collaboration, software maintenance
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