#251 - Mythos Back, Sonnet 5, Etched, LongCat - Last Week in AI

Our 251st episode with a summary and discussion of last week's big AI news!

Recorded on 07/01/2026

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In this episode:

Anthropic redeploys Claude Fable 5 after talks with the US government, adding new cybersecurity classifiers, drafting a jailbreak-severity framework with major partners, and expanding model-testing coordination; broader concerns remain about the inevitability of jailbreaks and uneven release constraints versus OpenAI.
Anthropic launches Claude Sonnet 5 with time-limited discounted pricing, improved agentic coding and benchmark performance, reduced misaligned behavior, and default cyber safeguards despite relatively weaker cybersecurity capability than top-tier models.
New tools and apps include Google NotebookLM generating TikTok-style vertical video summaries of uploaded research and Google releasing Nano Banana 2 Lite, a faster, cheaper image generator available via API.
Business and research updates span Etched’s push toward full-stack inference hardware with major funding and contracts, Baidu’s AI chip unit IPO ambitions, Agility Robotics’ SPAC plan, DeepSeek’s hiring expansion, and China’s open-source Longcat 2.0 MoE model with notable large-scale training and efficiency techniques alongside new long-horizon agent benchmarks.

Timestamps (note - these don't take into account dynamically inserted ads and therefore may be off by a couple of minutes):

Tools & Apps
(00:02:32) Trump drops restrictions on Anthropic's Mythos and Fable models | TechCrunch
(00:16:08) Anthropic launches Claude Sonnet 5 as a cheaper way to run agents | TechCrunch
(00:20:35) Google’s NotebookLM can sum up your research in a TikTok-style clip | The Verge
(00:22:08) Google introduces a faster, cheaper image generator with Nano Banana 2 Lite | TechCrunch

Applications & Business
(00:22:50) Etched Pulls 400+ Engineers From NVIDIA, TSMC & More to Build a New Frontier Inference Cluster For AI Which Is Already Worth $1B in Demand
(00:31:17) Baidu Rallies on AI Chip IPO Report
(00:33:54) Agility Robotics plans to go public via SPAC in a $2.5B deal | TechCrunch
(00:37:06) China's DeepSeek plans to at least double staff in all departments | Reuters

Projects & Open Source
(00:40:44) Introducing LongCat-2.0
(00:57:42) OSWorld2.0: Benchmarking Computer Use Agents on Long-Horizon Real-World Tasks
(01:01:33) TUA-Bench: A Benchmark for General-Purpose Terminal-Use Agents
(01:04:29) SWE-Together: Evaluating Coding Agents in Interactive User Sessions

#251 - Mythos Back, Sonnet 5, Etched, LongCat