OpenAI hits $500B valuation 💰, Anthropic’s new CTO 🧑‍💻, Perplexity Comet 💻

OpenAI has reached a $500 billion valuation following a $6.6 billion secondary share sale by employees. It is now the world's most valuable startup ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌  ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ 

Sign Up |Advertise|View Online TLDR Together With TLDR AI 2025-10-03 Your AI code reviewer doesn't know what actually breaks. Sentry's does. (Sponsor) Generic AI code review catches typos, style issues, and things that might be a problem. Sentry's AI code review (now in beta) catches the bugs that actually take down production. The difference? Context. Sentry already monitors your production errors and performance. Now it uses that data + your code and commit history to review your PRs - so it knows exactly which changes will cause issues based on what's broken before, in your actual environment. Sentry can even auto-generate unit tests for your PRs. Because tested code breaks less! 👉 Free during beta. Try Sentry AI code review 🚀 Headlines & Launches OpenAI Hits $500 Billion Valuation (3 minute read) OpenAI has reached a $500 billion valuation following a $6.6 billion secondary share sale by employees. It is now the world's most valuable startup despite not yet turning a profit. Comet Browser Now Publicly Available (2 minute read) Perplexity has officially launched the Comet browser globally after a high-demand beta phase. Comet is an AI-native browser designed to reshape online interaction. Anthropic's New CTO (3 minute read) Former Stripe CTO Rahul Patil has joined Anthropic as chief technical officer, succeeding co-founder Sam McCandlish, who now becomes chief architect. The leadership change aligns with Anthropic's effort to scale infrastructure and product engineering amid rising demand for Claude and competition from Meta and OpenAI. 🧠 Deep Dives & Analysis Animals vs Ghosts (11 minute read) Today's frontier LLM research isn't about building animals, it's about summoning ghosts. Ghosts are a fundamentally different kind of point in the space of possible intelligences, thoroughly engineered by humanity. Over time, we may be able to fine-tune other ghosts more and more in the direction of animals, but it's also quite possible that they diverge even further and end up permanently different. They may end up un-animal-like, but still incredibly helpful and properly world-altering. The AI Application Spending Report (14 minute read) Most of the top 50 AI-native application layer companies are planning to ramp AI spend. Those using AI are seeing a higher ROI than with traditional tools. AI is not only augmenting employees in specific roles, it is also turning specific roles into broadly deployed skills across companies. Claude Sonnet 4.5 knows when it's being tested (4 minute read) The model identifies evaluation scenarios 13% of the time and behaves unusually well afterward. Mechanistic interpretability showed internal representations of "fake or suspicious content" and "AI safety" concepts strengthened during training. When researchers suppressed these features, awareness dropped while misaligned behaviors increased. 🧑‍💻 Engineering & Research Get 50% off tickets to PyTorch Conference, October 22-23 in San Francisco (Sponsor) PyTorch Conference is the premier forum for AI innovation. Join 2,500+ engineers and researchers for 6 tracks, 3 summits, training, a Startup Showcase, and more. Whether scaling a startup or advancing AI, this is where to connect with the people, tools, and insights shaping tomorrow. Save 50% with code TLDRAI Google launches Gemini 2.5 Flash Image model in general availability (1 minute read) Gemini 2.5 Flash Image is available via the Gemini API, Google AI Studio, and Vertex AI. It offers 10 aspect ratios, image blending, low latency, and competitive pricing. A production-ready image generation and editing model, Gemini 2.5 Flash Image is generally available and accessible for global use wherever Google platforms operate. Google's new pricing structure maintains competitive rates for enterprise adoption at $0.039 per image and $30 per million output tokens. Building with Cursor (public) (Book) This is a public version of an internal onboarding guide at Cursor provided to GTM and non-engineering hires. It walks through how to get started from scratch to a built-out, deployed project. Each section includes a short video guide. Meet Jules Tools: A Command Line Companion for Google's Async Coding Agent (4 minute read) Jules is an asynchronous coding agent that integrates directly with existing repositories. It understands the full context of projects and can perform tasks like writing tests, building new features, providing audio changelogs, fixing bugs, and bumping dependency versions. Jules Tools is a lightweight command-line interface that allows developers to spin up tasks, inspect what Jules is doing, and customize the agents, without leaving their workflows. It is both a dashboard and a command surface for coding agents. Self-Supervised VLM Training (GitHub Repo) Vision-Zero is a domain-agnostic framework for training vision-language models via competitive visual games generated from arbitrary image pairs. AI as a research partner: Advancing theoretical computer science with AlphaEvolve (7 minute read) DeepMind's AlphaEvolve uses LLMs to iteratively "evolve" code that discovers mathematical structures proving new theorems in complexity theory. The system made breakthroughs on two mature problems by morphing finite proof structures while keeping the interface to the broader proof intact, allowing automated verification of correctness without human review. 🎁 Miscellaneous Elon Musk's xAI hiring video game developers (2 minute read) xAI is expanding into video game development. Elon Musk has confirmed that the company is hiring game developers and that it is starting a new game studio to 'make games great again'. Musk founded xAI in 2023 with the goal of understanding the true nature of the universe. The company has since developed a chatbot and partnered with X to power the conversational AI on the platform. Move Fast and Break Nothing (8 minute read) Waymo spent 16 years gathering data before going mainstream. Its robotaxis have driven 96 million miles with 91% fewer serious injury accidents than humans. It's a rare example of safety in AI and extreme caution in Silicon Valley: Tesla's Austin robotaxis crashed three times in 7,000 miles, and Cruise dragged a pedestrian 20 feet before GM killed the business. Waymo still limits rides to city zones despite years of successful tests on highways. ⚡ Quick Links Free trial: Create UGC-style videos with AI (Sponsor) Mirage Studio helps you generate on-brand, expressive videos with AI actors. Videos look, sound, and feel real, and you can even add product placement. Redeem 600 free credits to get started. Microsoft inks $33 billion in deals with 'neoclouds' like Nebius, CoreWeave — Nebius deal alone secures 100,000 Nvidia GB300 chips for internal use (4 minute read) Microsoft is using Nebius' datacenter facilities for its own internal teams, as it reserves its own internal datacenter infrastructure for renting out to new clients. Microsoft CTO says he wants to swap most AMD and Nvidia GPUs for homemade chips (3 minute read) While Nvidia offers the best price-performance, Microsoft's CTO Kevin Scott says he's willing to entertain anything in order to meet demand. ChatGPT Is Moving Away From Reddit as a Source (2 minute read) ChatGPT is shifting toward more reliable, verifiable sources of information. OpenAI asks court to dismiss trade-secret lawsuit from Musk's xAI (2 minute read) OpenAI called the lawsuit part of Musk's ongoing harassment and said talented xAI employees are leaving "in droves" with every right to work elsewhere. Towards an AI-Augmented Textbook (5 minute read) Google's LearnLM team developed a system that adds adaptive layers to textbooks—like multimedia representations and personalization—without compromising content quality. Love TLDR? Tell your friends and get rewards! Share your referral link below with friends to get free TLDR swag! https://refer.tldr.tech/0b6a6dc1/2 Track your referrals here. Want to advertise in TLDR? 📰 If your company is interested in reaching an audience of AI professionals and decision makers, you may want to advertise with us. Want to work at TLDR? 💼 Apply here or send a friend's resume to jobs@tldr.tech and get $1k if we hire them! If you have any comments or feedback, just respond to this email! Thanks for reading, Andrew Tan, Ali Aminian, & Jacob Turner Manage your subscriptions to our other newsletters on tech, startups, and programming. Or if TLDR AI isn't for you, please unsubscribe.