Anthropic launches Claude Mythos 5 and Claude Fable 5; Andrew Ng introduces OpenCoworker desktop agent
Anthropic released Claude Mythos 5 and Claude Fable 5, two variants of the same frontier model that set new state-of-the-art results across software engineering, knowledge work, cybersecurity, and agentic coding benchmarks. Claude Fable 5 is the general-availability version with safety classifiers that restrict responses on security, biology, chemistry, and cutting-edge AI topics, priced at $10/$50 per million input/output tokens; Mythos 5 is restricted to selected partners via Project Glasswing. Separately, Andrew Ng and collaborators released OpenCoworker, a free open-source desktop agent harness built on top of aisuite, designed to give users privacy-preserving agentic workflows with their own API keys or local models. The newsletter also contextualizes the broader shift toward LLM-driven agent harnesses as frontier models have become capable enough to reliably drive next-action decisions.
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Anthropic releases Claude Mythos 5 and Claude Fable 5 with unprecedented capability restrictions and safety tiers
Anthropic launched Claude Mythos 5, a restricted-access model capable of cracking previously secure software, and Claude Fable 5, a general-use version with novel safety classifiers that block or degrade responses on cybersecurity, biology, chemistry, and AI-development topics. Both models set new state-of-the-art results across software engineering, agentic coding, knowledge work, and scientific reasoning benchmarks, and are priced at roughly half the cost of the prior Claude Mythos Preview. Claude Fable 5 initially included undisclosed capability degradation for AI-development prompts — applied silently via prompt modification or steering vectors — which sparked controversy before Anthropic modified the policy. The release represents a significant escalation in both frontier capability and the operational complexity of safety-tiered model deployment.
The Batch: Claude Mythos 5 / Fable 5 debut, Apple AFM 3, Google Live Translate, OpenAI IPO filing, FrontierCode benchmark
Anthropic launched Claude Fable 5 (a safety-guardrailed model) and Claude Mythos 5 (same underlying model with safeguards removed, for vetted cyberdefense/infrastructure users via Project Glasswing with US government collaboration), both priced at $10/$50 per million tokens. Apple released five new Apple Foundation Models (AFM 3) spanning on-device and cloud tiers, built with Google and Nvidia infrastructure. Additional headlines cover Google's Gemini 3.5 Live Translate (70+ languages, real-time), OpenAI's confidential SEC IPO filing, a NotebookLM upgrade to Gemini 3.5, and Cognition's FrontierCode benchmark for code-quality evaluation where Claude Opus 4.8 leads at 34.3%.
Claude Opus 4.8 Launches with Improved Honesty; Anthropic Previews Mythos-Class Models and Dynamic Workflows
Anthropic released Claude Opus 4.8 with improvements in coding, reasoning, agentic tasks, and notably better uncertainty flagging—approximately four times less likely than Opus 4.7 to let code flaws pass uncommented. Alongside the model, Anthropic introduced dynamic workflows in Claude Code enabling tens to hundreds of parallel subagents for large-scale engineering tasks, an effort-control slider, and a 3x price cut on fast mode. Anthropic also previewed Mythos-class models, positioned above Opus in capability, currently available to a limited set of organizations for cybersecurity work pending broader safety clearance. The same digest covers MiniMax M3 (open-weights, ~60% SWE-Bench Pro), Nvidia's RTX Spark superchip, Cosmos 3 world model, and a GR00T/Unitree robotics partnership.
Anthropic Releases Claude Opus 4.5 with State-of-the-Art Coding, Agent, and Computer Use Capabilities
Anthropic has released Claude Opus 4.5, positioning it as the best model in the world for coding, agentic workflows, and computer use, with pricing reduced to $5/$25 per million input/output tokens. The model demonstrates significant token efficiency gains—up to 65% fewer tokens than prior models on equivalent tasks—alongside improvements in long-horizon autonomous task execution, multi-step reasoning, and self-improving agent behavior. The release is accompanied by updates to Claude Code, the Claude Developer Platform, and integrations with Excel, Chrome, and desktop environments. Early partner feedback from GitHub Copilot, Cursor, Notion, Warp, and others reports measurable benchmark improvements and new use cases previously out of reach.
Andrew Ng introduces OpenCoworker, an open-source desktop AI agent harness
Andrew Ng and collaborators Rohit Prasad and Devika Verma have released OpenCoworker, a free open-source desktop agent built by extending the aisuite library to support agent harnesses. The tool allows users to connect frontier LLMs (OpenAI, Anthropic, Google) or local models via Ollama to desktop tasks including file access, messaging, and workflow automation, with privacy as a design priority. Ng frames this as a response to data-retention concerns with commercial desktop agents, citing Anthropic's Fable release as a recent example of policy opacity. The post also provides a concise overview of the current desktop agent landscape and the shift toward LLM-driven agentic loops.
Anthropic Releases Claude Mythos Preview with Extraordinary Cybersecurity Capabilities, Forms Project Glasswing Consortium
Anthropic has published a 244-page model card for Claude Mythos Preview, a large language model not yet commercially available, which broadly outperforms Claude Opus 4.6 and is described as 'strikingly capable' at identifying and exploiting code vulnerabilities. To mitigate risks before potential release, Anthropic assembled Project Glasswing, a consortium including AWS, Apple, Google, Microsoft, CrowdStrike, Nvidia, and 40+ other organizations, funded with $100 million in API credits and $4 million in open-source security donations. This marks the first time Anthropic has published a model card without making the model commercially available, signaling an unusual safety-first deployment posture. The issue also includes commentary from Andrew Ng on AI's impact on software engineering jobs, arguing against an 'AI jobpocalypse' narrative.
Andrew Ng commentary on Anthropic's Claude Fable 5 restrictions and U.S. export controls on frontier AI models
Andrew Ng's The Batch editorial covers two significant recent events: Anthropic releasing Claude Fable 5 (a guardrailed version of Claude Mythos 5) with terms restricting use for competing LLM development, and the U.S. Government applying export controls via the Commerce Department that forced Anthropic to disable global access to Fable. Ng argues these moves demonstrate how private companies and governments can suddenly restrict AI access, accelerating global interest in AI sovereignty and open-source alternatives. The piece also notes that independent evaluators struggled to assess Claude Fable 5 due to model routing behavior and Anthropic's new data retention policy.
Claude Opus 4.6 Released with 1M Token Context, Agentic Coding Advances, and State-of-the-Art Benchmarks
Anthropic has released Claude Opus 4.6, its most capable model to date, featuring a 1M token context window in beta, improved agentic coding and planning capabilities, and adaptive thinking with developer-controlled effort levels. The model claims top scores on Terminal-Bench 2.0, Humanity's Last Exam, GDPval-AA, and BrowseComp, outperforming OpenAI's GPT-5.2 by 144 Elo points on GDPval-AA. New product features include agent teams in Claude Code, context compaction for long-running tasks, and Claude in PowerPoint (research preview). Pricing remains unchanged at $5/$25 per million input/output tokens.