A developer has released a tool that repurposes existing Codex CLI credentials to access the OpenAI API, potentially offering a lower-cost alternative for developers seeking LLM capabilities.
The project, called ‘llm-openai-via-codex’, was announced by Simon Willison on his blog and follows an earlier post about GPT-5.5. The tool essentially “hijacks” Codex credentials—which are typically used for Microsoft’s coding assistant—to make API calls to OpenAI’s language models.
This approach could be particularly attractive to developers in regions where OpenAI API pricing is high or where access is limited, as it leverages existing infrastructure rather than requiring new subscriptions. The tool is currently at an early release stage (0.1a0) and may require technical expertise to set up.
The development highlights ongoing efforts to optimize access to advanced AI models and explores alternative distribution methods beyond direct API offerings. It also raises questions about credential usage policies and the evolving landscape of LLM accessibility.