Fable 5.1 just smoked ASTRA...

Anthropic just dropped Claude Fable 5.1 and Mythos 5.1 — a big jump in long-horizon agentic work, with prompt-cache reads now 4x cheaper and the model burning far fewer tokens to do the same job. The timing is the story: it landed right as OpenAI announced its plans for Astra, the first model it says crosses "Critical" cybersecurity capability. I put Fable 5.1 to work immediately — a fully-voiced Tarkov-style extraction game with an auto mode, and a replica of Stanford's generative-agents "LLM Village" — each built in roughly 10–15 minutes.