Developer role is Incompatible Locally Deployed Model Interface

Resolved 💬 6 comments Opened Jan 16, 2026 by gzgzgzgz-tt Closed Jan 17, 2026

💡 Likely answer: A maintainer (etraut-openai, contributor) responded on this thread — see the highlighted reply below.

What version of Codex is running?

0.80.1

What subscription do you have?

in 0.80.1 codex introduced a "developer" role message, while this customized role message breaks AI interfaces that have strict role validation.

Which model were you using?

_No response_

What platform is your computer?

_No response_

What terminal emulator and version are you using (if applicable)?

_No response_

What issue are you seeing?

in 0.80.1 codex introduced a "developer" role message, while this customized role message breaks AI interfaces that have strict role validation.

What steps can reproduce the bug?

What is the expected behavior?

_No response_

Additional information

_No response_

View original on GitHub ↗

6 Comments

etraut-openai contributor · 6 months ago

Can you provide more information about your configuration and the model you're ussing?

Are you using the "chat/completions" wire API or the "responses" API for your custom provider?

gzgzgzgz-tt · 6 months ago

Can you provide more information about your configuration and the model you're ussing? Are you using the "chat/completions" wire API or the "responses" API for your custom provider?

Hi @etraut-openai thanks for the question.

Yes I am using deepseek 3.1 with "chat/completions" wire API and the custom provider is from our company's model team. Seems old openai library has strict check on the roles.

ERROR: {"error":{"code":"InvalidParameter","message":"The parameter `messages.role` specified in the request are not valid: invalid value: `developer`, supported values are: `system`, `assistant`, `user`, `tool`. Request id: xxxx","param":"messages.role","type":"BadRequest"}

Here is some similar issue from other project: https://github.com/agno-agi/agno/issues/1747, https://github.com/agno-agi/agno/issues/1757

For backward-compatibility, should we consider this is a bug and find someway to mitigate it?

etraut-openai contributor · 6 months ago

We've announced that we're removing support for the old "chat/completions" API at the end of this month. We don't plan to invest any more time in it at this stage. Please switch to the "responses" API.

gzgzgzgz-tt · 6 months ago

The developer role seems only work for OpenAI official api, but NOT WORK in other OpenAI-like provider api yet

gzgzgzgz-tt · 6 months ago

We've announced that we're removing support for the old "chat/completions" API at the end of this month. We don't plan to invest any more time in it at this stage. Please switch to the "responses" API.

Hi @etraut-openai I don't think this issue has anything to do with the api mode. https://github.com/openai/codex/discussions/7782#discussioncomment-15502684 In this thread you will see the similar role issue with reponses mode. The developer role seems only work for OpenAI official api, but NOT WORK in other OpenAI-like provider api yet. So if codex support other models' usage, this should be a compatibility bug, right?

etraut-openai contributor · 6 months ago

Whose provider API implementation are you using? You mentioned that you're using an old openai library. I presume that's where the error is coming from? Does this library support the "responses" API? Can you find an updated library?