`model_reasoning_summary=none` no longer works (400 Bad Request)

[maflcko]

What version of Codex is running?

codex-cli 0.23.0

Which model were you using?

Any thinking model

What platform is your computer?

Linux 5.14.x86_64

What steps can reproduce the bug?

$ codex -c model=o4-mini  -c model_reasoning_summary=none --dangerously-bypass-approvals-and-sandbox exec 'Reply with just "hi"'
[2025-08-20T10:12:13] OpenAI Codex v0.23.0 (research preview)
--------
workdir: /home/user_1/git_dir
model: o4-mini
provider: openai
approval: never
sandbox: read-only
reasoning effort: medium
reasoning summaries: none
--------
[2025-08-20T10:12:13] User instructions:
Reply with just "hi"
[2025-08-20T10:12:14] stream error: unexpected status 400 Bad Request: {
  "error": {
    "message": "Invalid value: 'none'. Supported values are: 'concise', 'detailed', and 'auto'.",
    "type": "invalid_request_error",
    "param": "reasoning.summary",
    "code": "invalid_value"
  }
}; retrying 1/5 in 214ms…

What is the expected behavior?

Support None value, like it used to in the past and how it is documented:

codex/codex-rs/protocol/src/config_types.rs

Lines 32 to 33 in ee8c4ad

	/// Option to disable reasoning summaries.
	None,

codex/codex-rs/config.md

Lines 240 to 244 in ee8c4ad

	To disable reasoning summaries, set `model_reasoning_summary` to `"none"` in your config:
	```toml
	model_reasoning_summary = "none" # disable reasoning summaries
	```

codex/codex-rs/core/src/config.rs

Lines 149 to 151 in ee8c4ad

	/// If not "none", the value to use for `reasoning.summary` when making a
	/// request using the Responses API.
	pub model_reasoning_summary: ReasoningSummary,

What do you see instead?

The error above

Additional information

No response

[AdalaceV2]

Yeah, really unfortunate, I hate having my console spammed with the reasoning traces.

[zipkr13]

I've created a sample PR simply removing it from the documentation.

Would love to understand if this option is supposed to be supported or not. If a bug, PR #2517 should be closed in favor of a fix

[zipkr13]

Hi @aibrahim-oai / @pakrym-oai (just tagging top 2 oai related contributors)

I'd really like to get an answer here if possible, is model_reasoning_summary = "none" no longer supported and should be removed from the documentation?

Or is this a bug? FWIW I also appreciated hidden reasoning as my use case necessitated parsing through codex's raw text stdout and stderr. Hiding reasoning summaries made it easier.

Thanks in advance 🙏