For agents, the value is clearer still: structured JSON output, reusable commands and built-in skills that let models interact with Workspace data and actions without a custom integration layer.

The big headlines on this release are efficiency, with OpenAI reporting that GPT-5.4 uses far fewer tokens (47% fewer on some tasks) than its predecessors).

ChatGPT is now using its 5.4 Thinking model for deeper reasoning, and it's even better at handling "professional work." ...