termdeck
Codex CLI fix: Codex refuses a model as not supported for the account
The response is a 400 carrying an invalid_request_error. The model exists, your login does not cover it, and the CLI passed the name through without checking it against anything.
is not supported when using Codex with a ChatGPT account
Printed by Codex CLI.
Diagnosis
Which models an account can use depends on how it authenticated. A ChatGPT sign-in and an API key reach different lists, and so do different plan tiers, which is why a model a colleague picks without trouble is refused on your machine.
A model named on the command line or in config.toml is sent as written. Nothing local compares it against the list your account can see, so the first thing to know the name is wrong is the backend, and it answers 400.
The app-server has a model/list call and it answers for the login in use. Termdeck asks that rather than shipping a hardcoded catalog, because a static list is exactly what hides a new model from a picker while every other layer is already correct.
Check
| Run this | What a good answer looks like |
|---|---|
codex login status | Names the auth mode. ChatGPT and API key reach different lists, so this decides which set of models the next question is even about. |
grep -n model ~/.codex/config.toml | Finds a pinned model you may have forgotten. A model set here applies to every session and long outlives the one you were running when it broke. |
Every command here has been run on a real machine. Termdeck answers the same questions for every machine you have connected, without opening a terminal on any of them.
Fix
Let the CLI use the default your login carries. If that works, the name you pinned is the problem rather than the account.
A stale model line survives every update, and it is the usual reason this appears out of nowhere weeks after somebody set it.
Where the model is one an API key covers and a ChatGPT sign-in does not, signing in the other way is shorter than hunting for an equivalent.
Not this
The refusal came from the backend, and a newer CLI sends the same name to the same account. An update helps only when the model is so new that your CLI cannot name it at all, which fails differently.
FAQ
No. It means your login does not cover it. The same name can work on another account on the same machine.
A plan change, a switched login, or a model moving out of preview all change the list without anything on your machine changing.
Codex reads a default from its config, so a model line set once applies to every session afterwards.
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