There doesn't appear to be a systemic issue with the keys (low 401 rate and I can successfully follow your steps)

Evidence points to your API key being rejected. The thing to focus on here is the cURL request, since that eliminates anything weird Codex could be doing

You will get a 401 if that $V0_API_KEY variable is undefined, in case your export V0_API_KEY command executed in a different environment and the variable didn't carry over to when you ran your curl command, so make sure you test them back to back

1
➜  ~ export V0_API_KEY="v1:……………………………………………………………………………………………O"
2
➜  ~ curl -s -o /dev/null -w "%{http_code}
3
" \                              
4
  -H "Authorization: Bearer $V0_API_KEY" \
5
  -H "Content-Type: application/json" \
6
  -d '{"model":"v0-1.5-md","messages":[{"role":"user","content":"ping"}]}' \
7
  https://api.v0.dev/v1/chat/completions
8
200

I'll check with the v0 team to see if we have any better resources for debugging this

I couldn't get it to work too. I followed the v0 docs and have the provider vercel added in config.json , and then I have V0_API_KEY in env along side OPENAI_API_KEY (which seems to be the cause of the issue)

curl with V0_API_KEY returns 200 as well

I think it is an upstream issue reported in the codex repo: https://github.com/openai/codex/issues/987

GitHub

Can't use other provider model · Issue #987 · openai/codex

What version of Codex is running? 0.1.2505161243 Which model were you using? deepseek-chat What platform is your computer? Darwin 24.4.0 arm64 arm What steps can reproduce the bug? After downloadin...

and the issue seems to be related to being logged in with openai keys and then trying to switch to other providers.