Codex 0.142.4

If your company network routes everything through a proxy (proxy, a middleman server your network requests get handed off through, common on corporate firewalls) before it can reach the internet, Codex's Windows login flow used to not understand that setup. Now you can opt in to support for PAC (auto-config scripts), WPAD (auto-discovering the proxy), static proxy addresses, and bypass rules for which destinations skip the proxy. It's like a mailbox rule that always required mail to go through the building's security desk first — the system finally understands that rule, so your mail doesn't get stuck halfway.

When you've hooked up a lot of MCP servers (Model Context Protocol, the standard that lets the AI talk to external tools), the AI used to have to memorize every tool's full instruction manual just to know what was available. Now, where supported, the AI uses tool search instead (tool search, looking up the specific tool it needs on demand rather than memorizing the whole catalog), finding tools more accurately, while older models and plugins keep working fine. It's like having to memorize every book title on a whole library floor just to find one useful book — now you just search for what you want and get pointed straight to the shelf.

Plugin (plugin, an add-on package that extends Codex with extra features) developers can now ship a dedicated dark-mode (dark mode, the dark-background display mode meant for low-light use) icon, supplied through the plugin's own manifest or a remote plugin store, which swaps in automatically when you switch to a dark interface — no more glaring light-colored icons sitting on a dark background.

If you point the AI at a remote image link (HTTP/HTTPS image, a picture that lives on a server elsewhere and only loads via its URL), problems with the format or source used to silently stall or fail the whole flow with no clear reason. Now the system produces a clear validation error the AI itself can read and understand — 'here's why this image didn't work' — while inline pasted image data (data URLs) and local files are unaffected and keep working.

The safety classifier (safety classifier, the system that automatically judges whether a command is safe and decides whether to ask your permission first) used to sometimes wave through PowerShell (Windows's scripting language) commands containing executable code regions (AST, abstract syntax tree, a structured breakdown of code that computers can parse) it couldn't actually parse — treating 'can't read it' as 'must be safe.' Now anything the classifier can't read gets stopped for your manual approval instead, closing that 'unreadable so let it through' loophole. It's like customs that used to sometimes wave through suspicious items it couldn't identify; now anything it can't identify gets pulled aside and opened up first.

Code Mode (a mode where the AI calls tools by writing code directly instead of issuing commands one at a time) needs the model to supply specific metadata (metadata, extra information describing which features a model supports) to work properly. Picking an unsupported model used to just fail silently and leave you confused. Now the system proactively warns you up front: 'this model might not work well this way.'