stream error: unexpected status 400 Bad Request:
Resolved 💬 6 comments Opened Sep 11, 2025 by stretchcloud Closed Nov 9, 2025
💡 Likely answer: A maintainer (etraut-openai, contributor)
responded on this thread — see the highlighted reply below.
What version of Codex is running?
codex-cli 0.34.0
Which model were you using?
gpt-5
What platform is your computer?
Darwin 24.6.0 arm64 arm
What steps can reproduce the bug?
Upgrade the CLI to the latest one.
Set the ~/.codex/config.toml to authenticate using Azure OpenAI instance
Run codex
What is the expected behavior?
_No response_
What do you see instead?
<img width="638" height="906" alt="Image" src="https://github.com/user-attachments/assets/65cf80a9-d5fa-4ebc-a41d-93e4d6881f60" />
Additional information
_No response_
6 Comments
+1 Hitting this issue after updating to the latest version
Seems like a knows issue. https://github.com/openai/codex/issues/3451
Downgrade the CLI to 0.31.0. Worked for me.
can any one post their config.toml for the azure end point? somehow .31 is not working for me either and .29 was working and now it is not
I met similar issue, it is ' stream error: unexpected status 400 Bad Request: {"error":{"code":"BadRequest","message":"API version not supported"}};', I even downgrade to 0.31.0, it still doesn't work for me ;(
Getting this issue using our LiteLLM endpoint (which is going to azure for gpt-5 calls). Roll back to 0.31.0 does work for me.
I think this has been fixed. If you're seeing a similar error with the most recent version of codex, please open a new issue.