TransformerTrio at SemEval-2026 Task 13: Navigating Domain Shift and Representation Instability in Machine-Generated Code Detection

Avi Patel, Manthan Laddha, Pushti Sapovadiya, Pruthwik Mishra, Shrikant Malviya


Abstract
Detecting machine-generated code is increasingly challenging due to advances in code generation models and domain variation across programming tasks. We present our submissions to SemEval-2026 Task 13, evaluating detection in three settings: binary human vs. machine classification, multi-class generator attribution, and four-way authorship classification including hybrid and adversarial cases. We compare feature-based, transformer-based, and hybrid approaches under domain shift and limited supervision. Results show that domain-specific signals often dominate model decisions, degrading generalization when training and test distributions diverge. Increasing model complexity does not consistently improve performance in low-resource or cross-domain settings and may amplify spurious correlations. These findings emphasize robustness and feature alignment over model sophistication for reliable detection.
Anthology ID:
2026.semeval-1.140
Volume:
Proceedings of the 20th International Workshop on Semantic Evaluation (2026)
Month:
July
Year:
2026
Address:
San Diego, California, USA
Editors:
Ekaterina Kochmar, Debanjan Ghosh, Kai North, Mamoru Komachi
Venues:
SemEval | WS
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1015–1026
Language:
URL:
https://preview.aclanthology.org/ingest-acl-workshops/2026.semeval-1.140/
DOI:
Bibkey:
Cite (ACL):
Avi Patel, Manthan Laddha, Pushti Sapovadiya, Pruthwik Mishra, and Shrikant Malviya. 2026. TransformerTrio at SemEval-2026 Task 13: Navigating Domain Shift and Representation Instability in Machine-Generated Code Detection. In Proceedings of the 20th International Workshop on Semantic Evaluation (2026), pages 1015–1026, San Diego, California, USA. Association for Computational Linguistics.
Cite (Informal):
TransformerTrio at SemEval-2026 Task 13: Navigating Domain Shift and Representation Instability in Machine-Generated Code Detection (Patel et al., SemEval 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-acl-workshops/2026.semeval-1.140.pdf
Supplementarymaterial:
 2026.semeval-1.140.SupplementaryMaterial.zip