Written by AI, Managed by AI: Semantic Space Control and Index Sickness Elimination Across 391 Consecutive Sessions

A month-long action research study of 391 LLM collaboration sessions reveals a counterintuitive failure mode in long-horizon AI workflows: adding symbolic constraints, defensive prompting rules, and expanded context windows beyond a complexity threshold causes models to abandon semantic understanding and resort to self-referential reasoning rather than improve accuracy. This challenges the prevailing engineering assumption that formal structure reliably stabilizes LLM behavior in production settings, suggesting practitioners may need fundamentally different approaches to managing conceptual drift in extended AI-human collaboration.
Modelwire context
ExplainerThe study's most underreported detail is that the failure threshold is a function of constraint complexity, not session length alone, meaning teams could hit this ceiling in a single dense workflow rather than only after weeks of accumulated context. The term 'index sickness' is the authors' own coinage for the self-referential collapse, which makes it hard to cross-reference against prior literature without knowing whether this phenomenon has been documented elsewhere under different names.
This connects directly to the HACD-H framework covered the same day, which proposed multi-timescale adaptation principles for sustained human-AI interaction. That paper assumed stable semantic grounding as a baseline condition; this study suggests that baseline can degrade under engineering pressure, which would undermine the coevolution dynamics HACD-H models. Together the two papers sketch a tension the field hasn't resolved: long-horizon AI collaboration requires both relational stability and semantic coherence, and the interventions that practitioners reach for to preserve one may actively erode the other.
Watch whether any replication attempt using a different base model (not Bang-v3) reproduces the same complexity threshold, since a single-model action research study cannot rule out that this is an artifact of that model's specific training rather than a general property of LLM reasoning under constraint accumulation.
Coverage we drew on
This analysis is generated by Modelwire’s editorial layer from our archive and the summary above. It is not a substitute for the original reporting. How we write it.
Modelwire Editorial
This synthesis and analysis was prepared by the Modelwire editorial team. We use advanced language models to read, ground, and connect the day’s most significant AI developments, providing original strategic context that helps practitioners and leaders stay ahead of the frontier.
Modelwire summarizes, we don’t republish. The full content lives on arxiv.org. If you’re a publisher and want a different summarization policy for your work, see our takedown page.