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Codex Issues / #35148

Unknown model: gpt-5.6-sol on Codex CLI 0.145.0 and ChatGPT desktop

Open 💬 3 comments Opened Jul 24, 2026 by colossusmaoyuid-art
💡 Likely answer: A maintainer (github-actions[bot], contributor) responded on this thread — see the highlighted reply below.

What version of Codex CLI is running?

codex app

What subscription do you have?

plus

Which model were you using?

gpt-5.6

What platform is your computer?

macOS

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

_No response_

Codex doctor report

What issue are you seeing?

  • macOS
  • Codex CLI 0.145.0
  • Logged in using ChatGPT
  • GPT-5.5 works normally
  • GPT-5.6 Sol is displayed in the model picker, but requests fail with:

Unknown model: gpt-5.6-sol

  • The same problem occurs in the ChatGPT desktop app and Codex CLI.

What steps can reproduce the bug?

Uploaded thread: 019f9391-5fea-7e41-b783-855512f7ecdd

What is the expected behavior?

_No response_

Additional information

_No response_

View original on GitHub ↗

3 Comments

github-actions[bot] contributor · 1 month ago

Potential duplicates detected. Please review them and close your issue if it is a duplicate.

  • #34027

Powered by Codex Action

colossusmaoyuid-art · 1 month ago

This appears related to #34027, but the issue is still reproducible on
Codex CLI 0.145.0.

GPT-5.6 Sol works in ChatGPT Work on the web for the same account, while
both the ChatGPT desktop app and Codex CLI return:

Unknown model: gpt-5.6-sol

GPT-5.5 works normally in both local clients.

github-actions[bot] @.***>于2026年7月24日 周五18:06写道：

github-actions[bot] left a comment (openai/codex#35148) <https://github.com/openai/codex/issues/35148#issuecomment-5068608111> Potential duplicates detected. Please review them and close your issue if it is a duplicate. - #34027 <https://github.com/openai/codex/issues/34027> Powered by Codex Action <https://github.com/openai/codex-action> — Reply to this email directly, view it on GitHub <https://github.com/openai/codex/issues/35148?email_source=notifications&email_token=CFVVNZRCDSZCZ4T6XTSDMIT5GMYLJA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMBWHA3DAOBRGEY2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-5068608111>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/CFVVNZT22QKNJHGSHVMNZKL5GMYLJAVCNFSNUABFKJSXA33TNF2G64TZHM4TMNJUGE2TMNBZHNEXG43VMU5TIOJWG4ZTSNRXGEZ2C5QC> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/CFVVNZSFTYGHJD4GQYCZTN35GMYLJA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMBWHA3DAOBRGEY2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KUZTPN52GK4S7NFXXG> and Android <https://github.com/notifications/mobile/android/CFVVNZRY5H2XXR4VRNRQWJL5GMYLJA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMBWHA3DAOBRGEY2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2K4ZTPN52GK4S7MFXGI4TPNFSA>. Download it today! You are receiving this because you authored the thread.Message ID: @.***>
colossusmaoyuid-art · 1 month ago

Additional reproduction results:

Environment:

  • macOS
  • Codex CLI 0.145.0
  • ChatGPT authentication

All three GPT-5.6 variants fail locally:

  • gpt-5.6-sol: 400 model_not_found
  • gpt-5.6-terra: 400 model_not_found
  • gpt-5.6-luna: 400 model_not_found

GPT-5.5 works normally in the same CLI and desktop app. GPT-5.6 Sol also
works normally for the same account in ChatGPT Work on the web.

Therefore, this affects the entire GPT-5.6 family on the local Codex
backend and is not an exact duplicate of #31905, where Terra and Luna
reportedly worked.

毛宇 @.***>于2026年7月24日 周五18:10写道：

This appears related to #34027, but the issue is still reproducible on Codex CLI 0.145.0. GPT-5.6 Sol works in ChatGPT Work on the web for the same account, while both the ChatGPT desktop app and Codex CLI return: Unknown model: gpt-5.6-sol GPT-5.5 works normally in both local clients. github-actions[bot] @.***>于2026年7月24日 周五18:06写道： > github-actions[bot] left a comment (openai/codex#35148) > <https://github.com/openai/codex/issues/35148#issuecomment-5068608111> > > Potential duplicates detected. Please review them and close your issue if > it is a duplicate. > > - #34027 <https://github.com/openai/codex/issues/34027> > > Powered by Codex Action <https://github.com/openai/codex-action> > > — > Reply to this email directly, view it on GitHub > <https://github.com/openai/codex/issues/35148?email_source=notifications&email_token=CFVVNZRCDSZCZ4T6XTSDMIT5GMYLJA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMBWHA3DAOBRGEY2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L#issuecomment-5068608111>, > or unsubscribe > <https://github.com/notifications/unsubscribe-auth/CFVVNZT22QKNJHGSHVMNZKL5GMYLJAVCNFSNUABFKJSXA33TNF2G64TZHM4TMNJUGE2TMNBZHNEXG43VMU5TIOJWG4ZTSNRXGEZ2C5QC> > . > Triage notifications, keep track of coding agent tasks and review pull > requests on the go with GitHub Mobile for iOS > <https://github.com/notifications/mobile/ios/CFVVNZSFTYGHJD4GQYCZTN35GMYLJA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMBWHA3DAOBRGEY2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2KUZTPN52GK4S7NFXXG> > and Android > <https://github.com/notifications/mobile/android/CFVVNZRY5H2XXR4VRNRQWJL5GMYLJA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMBWHA3DAOBRGEY2M4TFMFZW63VGMF2XI2DPOKSWK5TFNZ2K4ZTPN52GK4S7MFXGI4TPNFSA>. > Download it today! > You are receiving this because you authored the thread.Message ID: > @.***> >