What is gpt-relay-codex-plugin-?

GPT Relay is a plugin for Codex, OpenAI's coding agent, that lets Codex send prompts to ChatGPT through your existing Chrome browser session instead of through an API. The idea is to give Codex access to ChatGPT features that are only available to logged-in users in the web interface, such as specific model versions, Deep Research mode, web search, and image generation. Because it works through the visible browser, it can use your actual account settings and plan rather than a generic API connection. Setting it up involves two parts. First, you install the plugin into Codex from its plugin marketplace using a simple command or the Codex UI. Second, you install the official Codex Chrome extension and make sure you are already logged into ChatGPT in that browser. Once both are in place, when Codex calls GPT Relay, the extension opens ChatGPT in the background, selects whatever model or mode you requested, sends your prompt, and then returns the response back to Codex. The plugin can return text replies in Markdown, pass along image files that ChatGPT generates, and export Deep Research reports as Markdown documents. It also handles file uploads if you turn on the file URL access permission in Chrome. If ChatGPT shows a login prompt, CAPTCHA, or a feature your account does not have, the plugin stops rather than silently substituting a different model. This is a community-built tool, not an official OpenAI product. It works by reading and clicking elements in the ChatGPT web interface, which means a ChatGPT design change could break it. The README is clear about this limitation and notes that the plugin only reports what is visible in the browser, not any hidden server-side state.