Recently, OpenAI officially announced a major technological integration: ending its dedicated programming model Codex as a separate product line. From now on, the core capabilities of Codex will be fully integrated into the GPT-5.5 main model. This means that after the GPT-5.4 version, there will no longer be a dedicated programming branch in the market, and GPT-5.3 has become the "farewell" of the standalone Codex model.

This move marks a profound shift in OpenAI's R&D approach, evolving from a "specialized plug-in" to an "inherent all-round" model. In the past, developers were accustomed to calling the Codex model, which was specifically optimized for code. However, with the significant performance leap of the general large model foundation, OpenAI believes that embedding programming capabilities as a fundamental attribute in the main model can more effectively integrate resources. In fact, the integrated GPT-5.5 shows significantly improved resource utilization when handling complex programming tasks.

For developers, the most direct change is reflected in usage cost and efficiency. Although the API call price of GPT-5.5 has increased by about 20%, due to the enhanced understanding ability of the model, the number of tokens consumed for executing similar programming tasks has actually decreased. This logic of "higher unit price, lower consumption" reflects the model's more accurate and efficient processing of logical code.

Looking back at Codex's history, it has experienced the ups and downs of being closed and then reintroduced. This time, its complete integration into the main model indicates that AI programming is no longer a "special skill" requiring independent maintenance, but rather a foundational indicator for measuring the intelligence level of general large models. OpenAI's move not only aims to improve product line efficiency, but also sends a signal to the outside world: future AI will no longer rely on fragmented toolkits; a sufficiently powerful general intelligent brain should itself possess top engineering practical capabilities.