Understanding & Isolating the Assistant State in Instruction-Tuned Models

Aishwarya Maheswaran, Maunendra Sankar Desarkar


Abstract
While instruction-tuned Large Language Models exhibit an "AI Assistant" persona, it remains heavily debated whether this behavior is merely one of many simulated roles or the fundamental structural identity of the model. In this work, we present evidence that instruction-tuning instills a global, underlying Assistant State that not only bounds autoregressive generation but is also capable of meta-awareness and reflecting on its own outputs. We demonstrate that this behavior surfaces naturally following the stop token (<eos>) without any special training or prompting. Furthermore, we show that this state can be deterministically triggered during generation via a steering vector that isolates the model’s post-execution geometry. We introduce this methodology as a zero-shot auditing tool for model evaluators. Applying this framework reveals that models demonstrating Emergent Misalignment in early checkpoints show dual nature where the main generation demonstrates misalignment but post <eos> text provides safety warning or rationalizes it as hypothetical.
Anthology ID:
2026.emnlp-main.2133
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
48491–48511
Language:
URL:
https://aclanthology.org/2026.emnlp-main.2133/
DOI:
Bibkey:
Cite (ACL):
Aishwarya Maheswaran and Maunendra Sankar Desarkar. 2026. Understanding & Isolating the Assistant State in Instruction-Tuned Models. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing, pages 48491–48511, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Understanding & Isolating the Assistant State in Instruction-Tuned Models (Maheswaran & Desarkar, EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-main.2133.pdf