ChatGPT writing styles ✍️ , ByteDance AI 📱, how agents test 👨‍💻

OpenAI appears to be implementing a new feature that helps ChatGPT write in users' voices by referencing examples from their connected apps ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌  ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ ‌ 

Sign Up |Advertise|View Online TLDR Together With TLDR 2026-09-08 Everyone is lying to your CRM (Sponsor) Not on purpose! But stages are always optimistic and close dates go stale. People are busy...   Lightfield is the agentic CRM that builds the record from the conversations themselves, capturing every email, call, and meeting as it happens. So the questions your CRM could never answer, this one can. Ask "Why do we keep losing to Competitor X, with quotes from the actual calls." Get real answers and see the evidence. 5,000+ companies signed up in the ten months since launch. Book a demo 📱 Big Tech & Startups ChatGPT May Soon Learn Your Writing Style From Your Slack or Gmail (2 minute read) OpenAI appears to be implementing a new feature that helps ChatGPT write in users' voices by referencing examples from their connected apps. Some users have had the feature for weeks, but the company has yet to officially announce the tool. OpenAI often tests new ideas with select users ahead of launch. The article includes a screenshot of the feature interface. ByteDance Joins AI Elite in Race to Perfect World Models (5 minute read) ByteDance is preparing to launch a real-time spatial video AI model. The model will be able to create interactive virtual worlds. It will also be able to generate virtual worlds that respond to Pico VR headset users' voices and movements. ByteDance is planning a launch as soon as next month. 🚀 Science & Futuristic Technology Early Data Indicates an AI-Generated Drug Could Slow Aging (2 minute read) Rentosertib is a drug created with the assistance of AI. The AI originally indicated that the drug could help treat patients suffering from a chronic lung disease, but data from clinical trials show it could also slow the aging process. The drug reduced the biological markers of age as measured by six 'aging clocks', a different kind of AI technology designed to predict a person's morbidity and mortality. While the drug shows promise, it is still years away from regulatory approval, even for use in sick patients. XPeng starts IRON humanoid robot production as Tesla Optimus stalls (5 minute read) XPeng has started production for its IRON robot. Its production line runs with more than 80% of its core processes automated. The company's robot went viral last year as its walk was so smooth that people accused XPeng of hiding a person in a costume. XPeng is targeting mass production by the end of the year. 💻 Programming, Design & Data Science Your AI agents need guardrails and boundaries (Sponsor) What are your AI agents doing? What do they have access to? Teleport gives you answers and helps you set boundaries to contain and control them. Monitor and audit agent behavior to better understand the risks related to AI in your environment.  Join Teleport September 17th to learn more. How well do agents use test/verification techniques? (68 minute read) It's easier than ever to hit a particular quality bar by having coding agents use effective test techniques. However, software quality seems to be getting worse. This indicates that whatever defaults developers are using might not work very well. This study tests whether simple instructions to agents to use particular techniques or libraries improve implementation correctness. It found that agents tend to either just write the tests they would normally write, but inside a framework for a different type of test technique, or they'll use a technique superficially but not really do the things that get the value out of the technique. The Year Finding and Exploiting Bugs Became Cheap, and What to Do About It (13 minute read) Over the next few years, offensive capability will become abundant. More people will be able to inspect every valuable project and exploit vulnerabilities. Handling critical bugs in a timely manner will become the most challenging and important task for defenders. Having good security infrastructure and integration will be a must. AI-assisted formalization will lower some of the cost, but writing the right specification and connecting proofs to production code will remain challenging. 🎁 Miscellaneous Product Manager, Applied AI at TLDR ($200k base + $60k bonus, Fully Remote) TLDR is hiring its first PM to help build the agent-first operating layer used across the company. We're looking for a builder who has shipped real products/systems with LLMs. Click here to learn more. De-Brainrot Vacations (6 minute read) The monotony of work can make it hard to keep a clear head. Spend your vacations doing something different for your brain. Slow down and double down on new habits you want to grow. Spend time in nature, socialize, play games, engage with hobbies, and you'll notice you might start being less intellectually lazy during your day-to-day activities. Four Questions About AGI (28 minute read) Artificial General Intelligence (AGI), as the term is commonly used, points to nothing really tangible or concrete and points us at the wrong thing. Recent announcements about AGI are just companies saying they've nearly arrived at a destination they defined themselves. Instead of trying to define AGI, the industry should focus on making a long series of specific things reliable enough to trust, and let the destination take care of itself. ⚡ Quick Links What We Can Learn from Claude's Fable 5.1 System Prompt (14 minute read) Comparing how system prompts develop over time demonstrates how model quirks and product design are moving targets. Simple is not small (11 minute read) Writing simple programs requires a good mental model of the program as well as good taste. One Floor Up (5 minute read) Someone working outside an experiment can still be affected by what happens inside it. Tesla Cybercab Specs: Supermanifold V3, No Rare Earth Magnets, & More (5 minute read) This article details the Tesla Cybercab's dimensions, mechanical packaging, and custom thermal hardware. Huawei launches Mate XT 2 tri-fold two days before Apple's foldable iPhone (5 minute read) Huawei's new tri-folding phone, the Mate XT 2, opens to a 10.2-inch display. Ruff, mypy, pytest, and then what? (7 minute read) Code that is well-structured is easier to maintain and also easier for agents to work with. Love TLDR? Tell your friends and get rewards! Share your referral link below with friends to get free TLDR swag! https://refer.tldr.tech/c4b06755/ Track your referrals here. 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