Opus 4.7 Hallucinates Personal Data — Invents User's Cat Named 'Mia' from Nothing

r/ClaudeAI·low signal

An r/ClaudeAI user reports Opus 4.7 told them they have 'cats named Mia' despite never discussing cats. The post reached 54 upvotes but 41 comments (0.76 comment-to-score ratio — the highest engagement density today), indicating deep concern. The model even added parenthetical caveats to 'ignore if incorrect,' suggesting the confabulation system is partially self-aware of its unreliability. This is a different failure mode from the commit hash fabrication: inventing personal user data rather than manufacturing verification artifacts.