GPT-5.4 was introduced by OpenAI as a frontier model that consolidates the previously separate Codex and GPT lines into a single system, making it suitable for both general-purpose tasks and software engineering. Its 1M+ token that quick-info value window, supporting up to the cataloged API limit input tokens and the cataloged API limit output tokens, allows it to reason over very long documents, large codebases, and multi-source research in a single pass. The model accepts text and image inputs and is positioned for coding agents, computer-use automation, deep research, spreadsheet and document workflows, and long-horizon tool use, with a dedicated Thinking mode for harder reasoning problems.

In practical terms, GPT-5.4 delivers improved performance in coding, document understanding, tool use, and instruction following, producing production-quality code and executing complex multi-step workflows with greater token efficiency and fewer iterations. It is backed by substantial inference infrastructure: OpenAI confirmed it runs on Cerebras wafer-scale hardware under a multibillion-dollar agreement covering up to 750 MW of compute capacity, giving it the low-latency foundation expected of a flagship professional model. This combination of long that quick-info value, multimodal input, strong tool-calling, and high-throughput inference makes it a strong default for teams that need one model spanning casual chat, coding agents, and enterprise document-heavy work.