Work Cloud runs sandboxed tasks with Sol, Luna, and Terra, while Work Local automates files and programs on your computer.
OpenAI announced ChatGPT Work on July 9th and has iterated rapidly since. The product splits into two distinct offerings: Work Cloud, which runs in the browser and mobile apps, and Work Local, which is the desktop app formerly known as Codex. The analysis centers on Work Cloud and its differences from standard Chat.
Work Cloud lives at chatgpt.com and inside the ChatGPT mobile apps. A tab selector presents Work as an alternative to Chat. The biggest additions over Chat include a code execution environment with internet access, a headless Chrome browser, a persistent filesystem shared between sessions, the ability to publish ChatGPT Sites, and the option to run sub-agent sessions.
For builders and operators, the practical difference is task completion. OpenAI says to use Chat for answers and explanations, and Work for deliverables such as briefs, decks, analyses, and recurring updates. Work also introduces model choices: GPT-5.6 Sol, Luna, and Terra with reasoning levels from Light to Ultra, plus GPT-5.5 options, whereas Chat offers a different model selection.
Operators should watch for Ultra reasoning mode, which appears to delegate more eagerly to sub-agents. Scheduled prompt automations may arrive in both Work and Chat. Because Work sessions bill against your Codex allowance, heavy users should monitor usage. OpenAI continues to iterate on ChatGPT Work, so expect the feature set to shift.
What matters
- OpenAI launched ChatGPT Work on July 9th as a tabbed alternative to standard Chat.
- Builders get code execution, a headless Chrome browser, and a persistent filesystem across sessions.
- Watch for Ultra reasoning to delegate more eagerly to sub-agents with Sol, Luna, and Terra.
Why it matters
Watch for Ultra reasoning to delegate more eagerly to sub-agents with Sol, Luna, and Terra.
This GenAI News article was prepared in original wording using reporting and materials published by Simon Willison’s Weblog. Source reference: https://simonwillison.net/2026/Aug/30/understanding-chatgpt-work/.
Drafted by the GenAI News review pipeline.