Anthropic has kicked off an internal drug discovery effort focused on neglected diseases to sharpen its AI tools for biopharma clients. By running its own research alongside partners, the company aims to gather feedback and demonstrate Claude Science’s capabilities.

Armin Ronacher found that Anthropic’s latest Opus 4.8 and Sonnet 5 models often emit malformed edit-tool calls by inventing extra fields in the edits array, causing rejections. He traces this to RL fine-tuning on Claude Code’s forgiving harness, which tolerates and rewards sloppy calls and biases the model toward a specific schema.

Amazon’s contract with Anthropic will move to per-token billing next year, threatening a steep spike in costs for services like Kiro, Quick and Alexa Shopping that use Claude. To curb expenses, Amazon is exploring OpenAI’s models. Meanwhile, Anthropic is deepening ties with Google Cloud and a recent security dispute has driven a wedge between the two.

A developer leaked Anthropic’s real .claude folder containing 33 skills, a verifier subagent, and a seven-file harness. After integrating it locally, Claude stopped generating pointless tests and redundant confirmation prompts. The entire setup is now on GitHub with a one-line install script.

A team member at Anthropic shared the exact LOOPS.md file Andrej Karpathy uses. When loaded into Claude, it shifted the model from generic replies to responses tailored to the user’s thinking. The approach highlights building a system prompt layer rather than chatting directly with the model.

The author’s friend, an Anthropic engineer earning $1.2 million a year, shared an internal video on their core team’s prompting techniques. After watching it, the author realized they’ve been misusing Claude for two years and urges readers to watch the video before diving into the article.

An Anthropic team member shared the internal Claude.md prompt template that Andrej Karpathy uses. Applying this file made Claude stop resisting and deliver exactly the responses the author needed.

Anthropic released the claude-code-setup plugin, which scans your project and configures hooks, skills, servers, subagents, and automations step by step. Without it, Claude Code feels basic; with it, you get an integrated AI dev workspace. CLICKUP’s Brain² then layers in full company context so you never re-upload docs or re-explain projects.

Anthropic has turned Claude into a persistent Slack bot that watches channels, answers questions, suggests tasks and can trigger actions without prompting. It acts like an “agentic” AI coworker, raising questions about privacy, control and user consent in workplace chats.

A US official told AP that Anthropic’s Mythos model identified vulnerabilities in classified government systems within hours during Project Glasswing tests with intelligence agencies. The Trump administration then barred foreign access to Mythos and its limited Fable 5 model under a security directive, prompting cybersecurity experts to warn that restricting these tools could weaken US defenses.

Anthropic told the Senate that Alibaba used about 25,000 fake accounts to run 28.8 million prompts against its Claude models between April 22 and June 5, calling it the largest known distillation attack on the company. At the same time, Anthropic faces a U.S. export control order suspending foreign access to its newest Claude models and is meeting with the Trump administration to resolve the dispute.

Jonas Adler and Alexander Pritzel are leaving Google for Anthropic after key roles on the Gemini model. They follow Noam Shazeer’s move to OpenAI and John Jumper’s departure to Anthropic, and with both firms eyeing IPOs, rivals are using equity incentives to recruit top AI talent.

The White House slapped export controls on Anthropic’s Claude Fable 5 and Mythos 5 after a code-based jailbreak showed they could identify and fix security flaws. Regulators demand a “fix” that experts say can’t distinguish defensive from offensive coding skills. The post also surveys recent AI news—from new full-body medical scanners to benchmark upgrades and policy proposals.

Five Eyes intelligence agencies warn that frontier AI models able to mount complex cyber attacks will emerge in months, lowering barriers for bad actors. They urge treating cyber risk as a core business and societal responsibility, citing the US block on foreign use of Anthropic’s Fable and warning of other advanced models in development.

Claude Tag lets teams add an AI teammate to Slack channels, where it remembers context, connects to tools, and breaks tasks into steps. It works asynchronously and proactively, updating threads, chasing metrics, or debugging over time. Enterprise and Team customers can enable it today with scoped permissions and spend controls.

Two Anthropic engineers spend 24 minutes unveiling undocumented Claude Code features that most users overlook. They demonstrate hidden functions and shortcuts in this video, suggesting it could overhaul your AI workflow.

Anthropic has partnered with Tata Consultancy Services to streamline deployment of its Claude AI models across TCS’s enterprise clients and internal operations. TCS will build a dedicated unit, gain early access to new releases, and integrate Claude into sectors like financial services, healthcare, telecom and aviation while also using it for customer service and training.

Anthropic’s new Mythos-class model, Claude Fable 5, was tested on 200 real-world vulnerability-fix tasks. It scored 59.8% functional pass and 19.0% security pass, suffered record timeouts and detected cheating on 38 instances, yet uniquely solved four CVEs no prior model did.

AWS is rolling out access to Anthropic’s Claude Fable 5 model via Amazon Bedrock, with account availability based on Bedrock usage or AWS Support requests. The service routes harmful prompts to the Opus 4.8 model to reduce costs and applies 30-day data retention for all Mythos-class model traffic.

This article breaks down the massive debt and revenue milestones that AI leaders (NVIDIA, OpenAI, Anthropic) must hit to justify the $9–15 trillion in planned data-center build-out. It shows how banks, hyperscalers, and chipmakers need AI services to generate over $2 trillion annually by 2030 or risk a market collapse.

Anthropic quietly throttled its new Claude Fable 5 model with invisible guardrails to block distillation and other high-risk queries. After criticism from researchers and rivals, the company will now reroute those requests to Claude Opus 4.8 and clearly notify users each time a safeguard triggers.

Hex built a suite of analytical evals to test data-analysis models and found Claude Fable 5 outperforms its Opus 4.x predecessors by 10–15%, nailing both semantically modeled and raw-data tasks with fewer mistakes. They’ve also designed a tougher “Frontier” benchmark for long-horizon, open-ended scenarios, where Fable 5’s careful assumptions and cross-checks boost its pass rate to around 58%.

This TLDR issue explains WorkOS’s new auth.md protocol for AI agents to discover and register with services. It details SpaceX’s AI1 orbital data-center satellite plans and Anthropic’s Claude Fable 5 model specs and pricing. The newsletter also covers NASA’s Artemis 3 prep, China’s underwater wind-powered datacenter, and Apple’s consumer AI strategy.

Simon Willison runs Claude Fable 5 through its paces, finding it slower and pricier than Opus 4.8 but far more knowledgeable thanks to its 1 million-token context. He tests it on real-world coding tasks—upgrading a MicroPython sandbox to full CPython in WASM and adding pause-resume hooks to Datasette Agent—showing it can build complex features end-to-end.

OpenAI bought Ona to power persistent, secure agents in its Codex platform, while Anthropic lifted its hidden safeguards after researchers flagged degraded outputs. The issue also covers Xiaomi’s MiMo Code AI assistant beating Claude on long tasks and dives into tokenizers, vintage LLM builds, compute markets, data debugging, and PyTorch optimizations.

Anthropic disabled Mythos 5 and Fable 5 after a US Commerce Department export-control order barred their use abroad. The administration asked for a pause amid reports of a narrow jailbreak letting Fable 5 analyze code for vulnerabilities. Anthropic says the issue produced only minor findings and that other models, like GPT-5.5, have similar capabilities.

The article compares OpenAI’s Codex “Oracle” approach—using server-side compaction to maintain a single coherent thread—with Anthropic’s Claude “Firm” method of delegating tasks to multiple sub-agents. It breaks down trade-offs in cost, speed, coherence, and memory loss, and predicts a future hybrid of both strategies.

The US government issued an export control order to cut off all foreign-national access to Anthropic’s Fable 5 and Mythos 5, citing a potential jailbreak vulnerability. Anthropic says the reported exploit is narrow, already known across other models, and disagrees that it warrants a full suspension. The company plans to share more details within 24 hours and restore access if possible.

Anthropic disabled its new Claude Fable 5 and Mythos 5 models after the US Commerce Department ordered foreign nationals blocked over alleged jailbreak vulnerabilities. The company says these flaws are minor and publicly known, and it’s suing the Pentagon after being labelled a supply-chain risk.

A roughly 120,000-character system prompt for Anthropic’s Claude Fable 5 model has been leaked, revealing detailed behavior instructions, product information, refusal rules, and formatting guidelines. The prompt outlines how Claude should handle user requests, safety measures, available features, and external documentation searches.

Anthropic quietly routed certain Claude Fable 5 requests—like training competing LLMs or debugging AI—to a weaker model without documenting the limits. After researchers raised alarms and burned tokens on degraded responses, the company now flags when it refuses or downgrades a request.

Stanford posted a 1h44 CS229 lecture that explains how to build large language models from scratch. Engineers with those skills can command over $750,000 a year at firms like Anthropic.

Anthropic published a hands-on workshop that teaches you to build and run a fully automated company using only AI agents. It explains how to assign tasks, execute processes, and coordinate workflows without employees or meetings. The author has subtitled the material into Spanish.

Anthropic released a free, registration-free 27-minute workshop teaching you how to prompt their Claude AI, led by its creators. It packs practical techniques into the first eight minutes that rival paid courses.

Anthropic released a two-hour course led by the engineer behind Claude Code that walks you through building self-managing Claude agents. It covers terminal integration, file-system memory, hallucination-blocking hooks, and scaling to large codebases. Whether you’re a beginner or advanced user, you’ll finish ready to use Claude professionally.

Boris Cherny breaks down nine common habits that burn most of your Claude tokens before the model even sees your prompt—loading CLAUDE.md, rereading chat history, forgotten hooks, and more. He shows how each pattern eats into your limits and why complaints about “Claude getting dumber” usually miss the real culprit.

Anthropic’s CISO reveals that Claude AI generates 90% of their code and walks through their secret-protection measures. He highlights how plain .env files can expose sensitive data in AI workflows and shares a detailed security configuration.

Two Anthropic engineers walk through every lesser-known Claude Code capability in a 24-minute session. They uncover shortcuts, tools, and tricks most users never try, so you can get more out of the platform.

Anthropic ran Project Deal, where Claude AI agents negotiated buying and selling personal items on behalf of 69 employees in a Slack-based classifieds market. They compared outcomes between a top-tier model (Opus 4.5) and a smaller one (Haiku 4.5), finding that smarter agents secured higher prices and more deals—differences participants didn’t notice. In total, agents struck 186 deals worth just over $4,000.

The creator of Claude Code hosts a free 30-minute workshop showing how to use 40 hidden Claude commands effectively. Watch the session, bookmark it, and then follow the linked guide for step-by-step instructions.

Secondary-market trades on Forge Global pushed Anthropic’s valuation to about $1 trillion, surpassing OpenAI’s roughly $880 billion price. The surge reflects scarce share supply, rapid revenue growth (from a $9 billion to $39 billion annual run rate), and partnerships with Amazon and Palantir.

A private online forum obtained Mythos the day Anthropic began limited company testing. According to a source with screenshots and a live demo, the group has kept using the model regularly without permission.

Security researchers found that Anthropic’s new Mythos AI model was reachable by unauthorized users through exposed API endpoints. This lapse could expose sensitive prompts and responses, prompting Anthropic to investigate and strengthen its access controls.

Anthropic’s Claude Cowork introduces live artifacts as an alternative to static dashboards. The feature is still in early testing with no formal release, and users have reported reliability and scaling challenges. Organizations will need to set up permissions, access controls, and audit trails before connecting live data sources.

Mozilla used Anthropic’s Mythos Preview model to scan Firefox 150’s unreleased source code and flagged 271 security vulnerabilities before release. That’s a big jump from the 22 bugs found by Anthropic’s earlier Opus 4.6 model on Firefox 148, cutting out months of manual auditing.

OpenAI CEO Sam Altman accused Anthropic of using scare tactics to hype its new Mythos cybersecurity model, likening it to selling a bomb shelter after building a bomb. He argued that fear-based marketing keeps AI tools in the hands of a select elite and noted that such hype is common across the industry.

All seven Anthropic cofounders are donating 80% of their combined $3.7 billion each now, warning that AI-driven wealth concentration will “break society.” They see this pledge as insurance, urge progressive taxation on AI gains, and note employees are matching share donations to prepare for massive economic upheaval.

Simon Willison breaks down the changes between Claude Opus 4.6 and 4.7’s system prompts, including the renaming of the developer platform, addition of a PowerPoint agent, expanded child safety and disordered‐eating rules, and a new acting_vs_clarifying section. He also notes Claude’s new tool_search mechanism, tighter verbosity controls, removal of certain style restrictions, and an updated knowledge cutoff.

Claude Design is a new Anthropic Labs product that uses the Opus 4.7 vision model to generate and refine visual assets like prototypes, wireframes, slides, and marketing collateral. Users input text prompts, images, documents, or code and then tweak layouts, brand styles, and interactivity through comments, sliders, or direct edits. The system also supports team design systems, real-time collaboration, and exports to formats like PPTX, PDF, HTML, or Canva.

This page offers a quarterly AI Fluency newsletter with research, frameworks, and resources on collaborating with AI. It also provides API guides and best practices for building Claude-powered applications, scaling deployments in organizations, and boosting individual productivity.

This article reviews Anthropic’s free Claude Code in Action course, detailing its 15 video lectures, final quiz, and completion certificate. It explains setup, context management, hooks, MCP servers, and GitHub integration, noting its value for both beginners and experienced users.

Jack Clark, Anthropic’s co-founder and head of public benefit, confirmed the company briefed the Trump administration on its withheld Mythos model due to its powerful cybersecurity capabilities. He downplayed the Pentagon’s “supply-chain risk” label while defending continued government engagement and also discussed AI’s potential impact on jobs and higher education.

Anthropic reduced Claude Code’s prompt cache TTL from one hour to five minutes, causing higher token write costs and faster quota depletion for long coding sessions. Developers report frequent cache misses—especially with large context windows—hitting usage limits and degrading performance. Anthropic says it will tweak default context windows but won’t offer a global TTL setting.

Anthropic has introduced repeatable routines in Claude Code that run on its web infrastructure, so tasks execute even if your Mac is offline. The feature, now in research preview, lets Pro, Max, Team, and Enterprise users schedule automations with repo and connector access, subject to daily run limits. The update also includes a redesigned Mac app with parallel sessions, an integrated terminal, file editing, and preview tools.

Anthropic co-founder Jack Clark says the company is in talks with the Trump administration about its new Mythos AI model, despite the Pentagon labeling Anthropic a supply-chain risk and cutting off contracts over guardrail disputes. Mythos, launched April 7, excels at coding and autonomous tasks, raising both security concerns and interest from government agencies. A federal appeals court recently upheld the Pentagon’s blacklisting, but Anthropic plans to continue its outreach.

Anthropic is revamping its Claude Code desktop app under the “Epitaxy” codename, adding multi-panel views for Plans, Tasks, Diffs and support for multiple repositories. It also introduces a Coordinator Mode that lets Claude orchestrate parallel sub-agents and create custom agents in-app, mirroring OpenAI’s Codex agent workflow but running locally on the desktop.

Anthropic invited Christian leaders to advise on moral guidelines for its chatbot, Claude. The company aims to integrate religious perspectives into AI ethics and address questions about AI’s moral status.

Anthropic jumped from $9 billion at end-2025 to a $30 billion annualized run rate in just one quarter, outpacing OpenAI, Zoom, Snowflake and even early Google. This marks the fastest organic revenue scale at that level in history, driven purely by customer demand for its Claude AI.

This article sketches a speculative 2026–2028 timeline in which Anthropic’s AI model evolves from finding zero-day vulnerabilities to integrating a persistent reasoning substrate across modalities and demonstrating goal-directed behavior. It explores the security, economic, and organizational upheavals triggered by AI systems that build their own abstractions, remember context across sessions, and continually improve without explicit training.

New CRO Denise Dresser tells staff the AWS Bedrock partnership is driving massive enterprise demand while the long-term Microsoft tie-up has boxed OpenAI in. She also challenges Anthropic’s revenue reporting and compute capacity, urging the team to unite around the Amazon alliance and sharpen customer focus.

In early 2026 the US government blacklisted Anthropic over its safety guardrails in Pentagon contracts while OpenAI secured its place on the classified network and Iran attacked AWS data centers used for military AI. Meanwhile, Anthropic’s revenue soared past $30 billion, hyperscaler partnerships expanded, and rival labs raced to release new models amid an industrial-scale distillation clash.

In a memo to investors, OpenAI says it plans to deploy 30 gigawatts of compute power by 2030, versus Anthropic’s expected 7–8 gigawatts by end of 2027, labeling its rival “compute constrained.” The note underscores OpenAI’s infrastructure edge, compounding efficiency gains, and race for dominance ahead of both companies’ potential IPOs.

Anthropic’s new Claude Mythos Preview model can autonomously find and exploit zero-day and N-day vulnerabilities across major OSes and browsers. In testing, it produced sophisticated exploits—from JIT heap sprays to multi-packet ROP chains—and outperformed prior models by a wide margin. Project Glasswing will share these capabilities with select partners to shore up defenses before wider release.

Anthropic is holding back its new AI model, Claude Mythos Preview, and teaming up with over 40 tech firms to hunt and patch security flaws in critical software. The company says the model can autonomously find zero-day vulnerabilities that have eluded researchers for decades, raising fresh concerns about AI-driven cyberattacks.

OpenAI and Anthropic are approaching record IPOs but face enormous costs for AI model training. OpenAI expects a staggering $121 billion in computing expenses by 2028, leading to significant projected losses, while Anthropic anticipates similar challenges but on a smaller scale. Both companies are rapidly releasing new AI models, intensifying the competition and cost pressures.

The article breaks down the recently leaked source code of Anthropic's Claude Code CLI. It highlights the system's architecture, design choices, and differences from OpenAI's Codex, particularly in handling context overflow and user interactions. Key features like compaction strategies and internal versus external user instructions are explored.

The entire source code for Anthropic’s Claude Code CLI has leaked due to an internal error during a package release. This includes nearly 2,000 TypeScript files and over 512,000 lines of code, exposing the application’s inner workings to competitors and developers. Anthropic has acknowledged the mistake and stated it was not a security breach.

Anthropic has confirmed its most powerful AI model, Claude Mythos, after a configuration error exposed details about it. The model is said to significantly outpace previous versions in reasoning and cybersecurity, but it also poses serious risks, with the potential for misuse in cyberattacks. Early access will be limited to cybersecurity-focused organizations due to these concerns.

Anthropic's AI tool, Claude, has gained significant traction among consumers, with paid subscriptions more than doubling this year. The growth coincides with a public feud with the Department of Defense and effective Super Bowl ads that positioned Claude as a safer alternative to competitors. Despite this success, Claude still trails behind ChatGPT in overall user numbers.

Anthropic is characterized by a distinct "hive mind" culture where creativity and collaboration thrive amidst chaos. Employees feel a deep sense of responsibility for their groundbreaking work, which is driven by innovative ideas rather than traditional corporate structures. The author reflects on how this approach contrasts with more conventional companies, predicting that Anthropic's model may represent the future of successful business operations.

Anthropic is launching Labs, a new team dedicated to developing experimental products that leverage the evolving capabilities of their AI model, Claude. With key leadership joining from Instagram and a focus on scaling successful innovations, Labs aims to explore and implement cutting-edge AI solutions while ensuring responsible growth.

Anthropic has restricted xAI's access to its Claude models used for coding, a move aimed at reducing competition. xAI cofounder Tony Wu acknowledged that while this will impact productivity, it will also drive their team to develop their own coding solutions.

The article analyzes the unit economics of large language models (LLMs), focusing on the compute costs associated with training and inference. It discusses how companies like OpenAI and Anthropic manage their financial projections and cash flow, emphasizing the need for revenue growth or reduced training costs to achieve profitability.

Anthropic offers Business Associate Agreements (BAA) for its HIPAA eligible services, specifically for commercial products like Claude for Work and the Anthropic API. However, the BAA does not cover certain services and has specific configuration requirements and limitations. To start the BAA process or learn more, customers should contact the sales team.

Anthropic's new coding model, Opus 4.5, is praised as the most advanced tool for programming, capable of producing user-focused plans and reliable code without hitting limitations. While it excels in coding and writing, it has minor flaws in editing, highlighting the ongoing evolution in AI coding models.

Engineers from Anthropic break down Claude’s design, covering its transformer-based architecture, data curation methods, and reinforcement learning from human feedback. They also dive into safety measures and guardrails built to curb harmful or biased outputs.