Claude Fable 5: Launched, Hyped, Banned by the Government | This Week In AI

Fable came and went in a week. Shane and Abhi break down the strangest model launch yet — Claude Fable 5, a Mythos-class model Anthropic said was too capable to release widely, until a US export-control directive made it vanish for everyone.

We cover the whole arc: the launch hype, the pricing that had people spending $1,000 a day, the silent fallbacks to Opus, the system-prompt leak, and the snitch that triggered a 90-minute shutdown. Then a stacked back half — China's open-weight surge, OpenRouter Fusion, loop engineering vs loopcraft, the agent-learning gold rush, OpenAI filing to go public, and Dario's new essay.

AI Agents Hour is a weekly livestream by Mastra CPO Shane Thomas and CTO Abhi Aiyer. Mondays 12PM Pacific.

📚 READ MORE Claude Fable 5 launch: https://x.com/claudeai/status/2064394146916229443 Pokémon beaten with vision: https://x.com/Baconbrix/status/2064418858073784530 Export-control announcement: https://x.com/anthropicai/status/2065597531644743999 Amazon/WSJ report (Theo): https://x.com/theo/status/2065665304882209132 David Sacks on the ban: https://x.com/davidsacks/status/2065853007619588171 Token capital (Satya Nadella): https://x.com/satyanadella/status/2066182223213293753 Siri as a harness (Weinbach): https://x.com/mweinbach/status/2065630219021492474 MiniMax M3 open weights: https://x.com/minimax_ai/status/2065436935188058208 GLM 5.2: https://x.com/zai_org/status/2065704919299235870 Kimi K2 Code High Speed: https://x.com/kimi_moonshot/status/2066467110960959833 Cohere North Mini Code: https://x.com/cohere/status/2064378058329526556 Gemma 4 on consumer hardware: https://x.com/unslothai/status/2065433326706684135 Diffusion Gemma: https://x.com/unslothai/status/2065107734916432189 OpenRouter Fusion API: https://x.com/openrouter/status/2065856853989270011 AI SDK harnesses (Vercel): https://x.com/vercel_dev/status/2065509970775519569 Swyx on loopcraft: https://x.com/swyx/status/2065307558198567206 OpenEnv joins Hugging Face: https://x.com/ben_burtenshaw/status/2063991191415267492 Adaline 2.0 / agent learning: https://x.com/adiix_official/status/2066172819952566643 Cognition Frontier Code: https://x.com/cognition/status/2064061031912288715 Ramp SWE-bench: https://x.com/RampLabs/status/2065485806605619304 AWS on AI-generated code: https://x.com/awscloud/status/2064449711155589396 OpenAI files to go public: https://x.com/OpenAINewsroom/status/2065088002335158753 OpenAI acquires Ona: https://x.com/OpenAINewsroom/status/2064094175541461220 Salesforce acquires Fin AI: https://x.com/fin_ai/status/2066493998852686074 Mistral in talks to raise: https://x.com/business/status/2065420995393941692 Dario's essay on the AI exponential: https://x.com/DarioAmodei/status/2064781775247950326

📚 MASTRA RESOURCES Mastra: https://mastra.ai Mastra on X: https://x.com/mastra_ai Mastra Discord: https://mastra.ai/community/discord Mastra GitHub: https://github.com/mastra-ai Learn Mastra in the world's first MCP-Based Course: https://mastra.ai/course Principles of Building AI Agents (Book): https://mastra.ai/books/principles-of-building-ai-agents Patterns for Building AI Agents (New Book): https://mastra.ai/books/patterns-of-building-ai-agents

WHAT IS MASTRA? Mastra is an open-source TypeScript framework designed for building and shipping AI-powered applications and agents with minimal friction. It supports the full lifecycle of agent development—from prototype to production. You can integrate it with frontend and backend stacks (e.g., React, Next.js, Node) or run agents as standalone services. If you're a JavaScript or TypeScript developer looking to build an agentic or AI-powered product without starting from first principles, Mastra provides the scaffolding, tools, and integrations to accelerate that process.

⏱️ CHAPTERS 00:00 Cold open & welcome 00:40 Claude Fable 5: the launch and the hype 01:53 The price problem and silent Opus fallbacks 06:42 Our experience + the system-prompt leak 08:51 The 90-minute export-control shutdown 12:40 Microsoft's "token capital" & where Fable goes 17:07 Apple at WWDC: Siri as a harness 17:57 China's open models: MiniMax M3, GLM 5.2, Kimi K2 21:11 Local-first: Cohere, AMD, Diffusion Gemma 24:58 OpenRouter Fusion & AI SDK harnesses 27:07 Loop engineering, loopcraft & OpenEnv 29:09 Agent learning & new coding benchmarks 32:14 AWS, the snitch & OpenAI's IPO 33:37 Salesforce, Mistral & Le Chaton Fat 36:42 Quick hits & a Fable eulogy