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BENIBIXCodex/Config Studio for Codex

Config Studio for Codex

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Quick tourHere, on the real controls8 steps, about a minute Full lessonsOpens in a new tab7 lessons, about 23 min

Config Studio for Codex

Configure

0changes0surfaces0files to write

nothing in the plan · nothing written to disk

Include config.toml: model and defaults
Include Sandbox and approvals
Include Permission profiles
Include Rules (.rules files)
Include AGENTS.md
Include Hooks
Include Skills
Include MCP servers
Include Custom agents
Include Subagent defaults
Include Profiles
Include Status line and terminal title
Include Interface and notifications
Include Shell environment
Include Features and memories
Include Model providers and local models
Include History and telemetry
Include Trusted projects
Include requirements.toml (admin)
Include Flags for one run
Include codex exec (scripts and CI)

0 / 21 surfaces0 changes

Include config.toml: model and defaults
Include Sandbox and approvals
Include Permission profiles
Include Rules (.rules files)
Include AGENTS.md
Include Hooks
Include Skills
Include MCP servers
Include Custom agents
Include Subagent defaults
Include Profiles
Include Status line and terminal title
Include Interface and notifications
Include Shell environment
Include Features and memories
Include Model providers and local models
Include History and telemetry
Include Trusted projects
Include requirements.toml (admin)
Include Flags for one run
Include codex exec (scripts and CI)

config.toml: model and defaults

tomlnot in the plandocumented

/

0 set

The main file: which model answers and how hard it thinks, web search, style, instructions from config and the context limits.

Here you set: The defaults every session starts from. Only what you set is written; the rest stays as Codex ships it.

Where it lives · 5 files· highest precedence first

1/etc/codex/requirements.tomlenterprise
2codex -c key=valuesession
3./.codex/config.tomlproject
4~/.codex/<name>.config.tomluser
5~/.codex/config.tomluser

When two of these disagree, the one higher in the list wins, so enterprise beats the rest.

Which config.tomlYours (~/.codex/config.toml) or this repository's (.codex/config.toml). A project file loads only when you trust the project, and its values beat yours for the model and the rest of this panel.

userYou, in every project: ~/.codex/config.toml.projectThis repository, for everyone who trusts it: .codex/config.toml.

Model5

ModelWhich model answers. Left empty, Codex uses its default, which follows your sign-in and plan.

Reasoning effortHow long the model thinks before it answers. Higher is slower and uses more of your limits; which levels exist depends on the model.

lowQuick. For small, clear jobs.mediumThe usual default.highThinks longer: plans and harder bugs.xhighLonger still, on models that offer it.maxDeeper than xhigh, on models that offer it.ultraThe deepest, on models and accounts that offer it.

Reasoning effort in plan modeA separate effort for planning, so a plan can think harder than the edits that follow it.

lowQuick. For small, clear jobs.mediumThe usual default.highThinks longer: plans and harder bugs.xhighLonger still, on models that offer it.maxDeeper than xhigh, on models that offer it.ultraThe deepest, on models and accounts that offer it.

Reasoning summariesWhile it thinks, Codex can show you a summary of its reasoning. This sets how long that summary is.

autoThe model picks the length (default).conciseA line or two for each step.detailedA fuller account of each step.noneNo summary: only the answer and what it ran.

Communication styleThe tone of its replies. Pragmatic is terse; friendly explains more.

pragmaticDirect and to the point.friendlyWarmer, explains more.noneNo personality instructions.

Tools2

Web searchCached is the default: results come from an index OpenAI keeps, which limits what an untrusted live page can inject. Live is the same as --search.

cachedFrom the search cache (default).indexedLive pages only when the index allows the request.liveFetch current pages from the web.disabledNo web search tool at all.

Model for /reviewA different model for code reviews started with /review.

Instructions3

Extra developer instructionsInstructions added to every session from config rather than from AGENTS.md. AGENTS.md is the better home for anything about a repository.

Most bytes of AGENTS.md readThe ceiling on all the AGENTS.md files together, 32 KiB by default. Past it, files further down are dropped.

Also read these as AGENTS.mdOther instruction file names to use in a folder that has no AGENTS.md, one per line.

Interface2

Open cited files inWhich editor a file citation in an answer opens.

vscodeOpens in VS Code (default).vscode-insidersOpens in VS Code Insiders.cursorOpens in Cursor.windsurfOpens in Windsurf.noneShows the path as plain text, no link.

Hide reasoning while it worksLeaves reasoning events out of the output, for a quieter screen or log.

Context2

Compact the context at (tokens)When the conversation reaches this many tokens Codex summarises it to make room. Lower means earlier and more often.

Most tokens one tool result may takeCaps how much of a long command output goes into the context.

Account2

Where your sign-in is keptThe keyring keeps the token out of a plain file in ~/.codex; auto picks the keyring when there is one.

autoKeyring when available, else a file.keyringAlways the system keyring (Keychain, Credential Manager).fileA plain file, ~/.codex/auth.json.ephemeralMemory only, gone when Codex exits.

Check for updates at startOff stops the update check when Codex starts.

config.toml: model and defaultsnot written

Nothing to write yet. The grey text in the fields is only an example: type your own values on the left, and the file they produce appears here.

Changes

0changes0surfaces0files to write

nothing in the plan · nothing written to disk

Changes

0

Nothing is off its default yet. Set something in Configure and every key you move is listed here, with what it was and what you made it.

What it writes

empty

Nothing is in the plan yet. Tick a surface in the rail to add what you have set to it; the plan is every file, across every tool, in one review.

Try it

Engines

Rules (.rules files)

Would Codex run this command?

codex.rules

Put a command to your rules: allowed, asked about or refused, checked command by command the way Codex splits a chain.

Your input

RulesOne a line: allow, prompt or forbidden, the command prefix, then -- and why. a|b at one position means either.
allow git add allow npm test prompt git push -- Pushing leaves this machine forbidden rm -rf -- Delete with a narrower path
CommandAs Codex would run it. A chain of plain words with &&, ||, ; or | is checked command by command.

Answer

Refused

rm -rf build matches a forbidden rule (rm -rf): Delete with a narrower path.

git add .: allow
rm -rf build: forbidden

Computed by codex.rules, the same function the tool pages are built on. Nothing you type here leaves the page.