Anthropic confirmed Claude Mythos, scoring 93.9% on SWE-bench Verified and 97.6% on USAMO. The model autonomously discovered zero-day vulnerabilities in every major OS and browser during testing, including a 27-year-old OpenBSD bug. Access restricted to 50 organizations under Project Glasswing.

OpenAI restructured Codex with separate Basic and Advanced tiers, adding app preview, scratchpad, a Pull Requests section, and inline comments on previewed UI. The split gives power users deeper integration while keeping the entry point accessible.

Microsoft open-sourced markitdown, converting PDFs, DOCX, PPTX, HTML and other formats into clean Markdown suitable for LLM context windows. Gained 3,600+ stars in its first week. Solves a pain point every RAG pipeline developer has hit.

Google's Agent Development Kit (adk-python) hit 8,200+ stars and emerged as the most fully-featured multi-agent framework this month. Meanwhile Block's Goose takes a different approach: local-first with native MCP support for tool integration.

Gemma 4's Apache 2.0 release sparked a wave of testing across the developer community. Medium posts and Reddit threads show it scoring competitively on code tasks when used with Claude Code. The 31B model's 256K context and zero licensing cost are driving rapid adoption.

Anthropic is building a major Claude Code desktop overhaul codenamed Epitaxy, featuring Coordinator Mode for parallel sub-agents, plan/task/diff panels, multi-repo support, and code preview. The power-user UI suggests Claude Code is evolving from a CLI into a full IDE.

Anthropic has received VC offers at valuations up to $800B, more than doubling its $380B February valuation. With annualized revenue at $30B vs OpenAI's $25B, it's the first time Anthropic leads on revenue. Over 1,000 enterprises spend $1M+/year on Claude.

Four Claude Code extension repos are trending on GitHub this week, collectively gaining 8K+ stars: andrej-karpathy-skills, claude-code-best-practice, claude-mem, and learn-claude-code. The pattern signals Claude Code is becoming a platform with its own ecosystem, similar to VS Code extensions circa 2018.

OpenAI released GPT-5.4-Cyber, a model fine-tuned for defensive cybersecurity, days after Anthropic's Mythos disclosure. Currently scaling to highest-tier API customers. The cybersecurity AI arms race between Anthropic and OpenAI is heating up fast.

Google open-sourced Magika, its internal AI file type detection tool with 99% accuracy across 200+ content types. Previously used to scan hundreds of billions of files weekly across Gmail and Drive. Now available for developers to build into their own pipelines.