After launching vibe coding app Codex for Mac, Sam Altman says he feels sad and useless

A day after OpenAI rolled out a new standalone Codex app for Apple computers, CEO Sam Altman shared an unusually personal moment about working with his own AI product. In a post on X, Altman said that while building an app using Codex was exciting and fun, the experience also left him feeling “a little useless” and unexpectedly sad.

Altman wrote that he recently used Codex to build an app on his own. Once the basics were in place, he started asking the AI for ideas to improve it. That’s when things took a turn. “At least a couple of them were better than I was thinking of,” he said, adding that the realisation made him pause. “I felt a little useless and it was sad.”

The tweet quickly caught attention, not just because of Altman’s honesty, but also because it came right after OpenAI launched Codex as a dedicated Mac app. The app, which is currently available to all ChatGPT users with Apple computers for a limited time, is designed to make “vibe coding” easier by letting developers work with multiple AI agents from a single place.

OpenAI describes the Codex app as a command centre for developers. Instead of chatting with one assistant at a time, users can run several AI agents in parallel, each working on different tasks or parts of a project. These agents operate in separate threads, organised by project, allowing developers to review changes, collaborate, and keep long-running tasks moving without losing track.

An AI agent, in this context, is more than just a chatbot. It can independently carry out tasks like writing and refining code on behalf of the user. Codex also includes a library of built-in skills, such as image generation, which helps agents handle work that goes beyond plain coding.

AI coding tools have seen massive adoption over the past year, and Codex is no exception. OpenAI said more than one million developers used Codex in the past month alone. The company first introduced Codex in April and made it widely available in October. The new Mac app is the latest step in pushing the product further, especially as competition heats up from rivals like Anthropic and Cursor, which are also targeting developers with similar tools.

Internally, Codex seems to have made a strong impression as well. Altman told reporters that it is “the most loved internal product we’ve ever had.” He added that the team at OpenAI has been using it heavily, calling the experience “totally amazing.” “I’ve been staying up late at night with excitement, building all sorts of things myself,” he said.

Access to Codex is usually tied to ChatGPT subscriptions, including Plus, Pro, Business, Enterprise and Edu plans, with options to buy extra credits. However, with the launch of the app, OpenAI has opened Codex to free users and its lower-cost Go tier for a short period. Existing paid users are also getting a temporary boost, with rate limits doubled across plans.