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Jun 2, 2025
LLM Fingerprinting Through Semantic Variability
Luiza Corpaci, Chris Forrester, Siddhesh Pawar
Summary
This project develops an LLM fingerprinting and analysis toolkit to increase transparency in AI routing systems, addressing Track 2: Intelligent Router Systems through two key investigations. We adapted semantic variability analysis to create unique behavioral fingerprints that can identify which specific models are operating behind opaque routing services, and conducted tool detection experiments under semantic noise to assess model robustness. Our findings demonstrate that models maintain high semantic robustness while our fingerprinting technique successfully distinguishes between different models based on their response patterns. These contributions aid the Expert Orchestration Architecture vision by providing practical tools for auditing multi-model AI systems, enabling organizations to understand which models their routers actually use and verify their reliability under real-world conditions, ultimately making router systems more transparent and trustworthy for production deployment.
Cite this work:
@misc {
title={
},
author={
Luiza Corpaci, Chris Forrester, Siddhesh Pawar
},
date={
6/2/25
},
organization={Apart Research},
note={Research submission to the research sprint hosted by Apart.},
howpublished={https://apartresearch.com}
}