Old Zhang's AI Learning

Jun 10, 2026 · Artificial Intelligence

Anthropic’s Claude Fable 5 and Mythos 5: Twin Models with a Shockingly Low Price and New Safety Switches

Anthropic released Claude Fable 5 and Mythos 5 as twin large‑language‑model variants that share the same base but differ only in safety‑classifier settings, offering 1 M‑token context, 128 k‑token output, a halved price, and a three‑layer real‑time safety system that routes risky requests to Claude Opus 4.8.