Originally published on Skila AI OpenAI's own September 2025 paper proved AI hallucinations are mathematically inevitable. The total error rate is at least 2x the yes/no error rate, and 9 of 10 frontier benchmarks reward guessing over honesty. Stop waiting for a fix. Plan around it. On September 4, 2025, Adam Kalai, Ofir Nachum, and Edwin Zhang from OpenAI — plus Santosh Vempala from Georgia Tech — published arXiv:2509.04664, "Why Language Models Hallucinate" . The paper proves that for any large language model trained on next-token prediction, hallucinations are not a bug. They are a mathematically unavoidable feature. Eight months later, the implications are landing. On May 12, 2026, Anthropic shipped 12 new legal Claude plugins and 20 legal connectors — deposition prep, bar-exam coaching, case-law research, file drafting, plus integrations with DocuSign, Thomson Reuters, Harvey, and Everlaw. AI is now being pushed into the single highest-stakes hallucination zone in the economy.…