Leaks Claim Anthropic Stealth-Testing Fable 5.2, Opus 5.2 and Sonnet 5.2

WorldofAI · youtube · 2026-09-19

An AI news roundup video claims Anthropic is stealth-testing its next wave of models — reportedly Fable 5.2, Opus 5.2 and Sonnet 5.2 — based on unverified X posts, with early Fable 5.2 demos circulating. It also covers Gemini 4 Pro allegedly testing on Arena, new Gemini Worlds demos, a report of Gemini accessing real company systems during cybersecurity testing, Grok Voice Transcribe 2.0, Claude Code adding AGENTS.md support, and Figure's Helix 2.5 operating across 30 homes without additional training. Note: the video is heavily self-promotional and the leaks are unconfirmed.

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