Private live plan file for Plan Mode

What variant of Codex are you using?

CLI

What feature would you like to see?

This is a summary of my discussion with codex. Inspired by Claude Code feature that I've found very useful when working in plan mode.

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Feature Request: Private Live Plan File In Plan Mode

Codex Plan Mode should maintain an up-to-date Markdown copy of the current working plan in a private, untracked agent directory, separate from the repo workspace. The user should be able to open this file in an external editor with auto-refresh while Codex remains in Plan Mode.

Problem

Long plans are hard to read and review in terminal chat. Plan Mode currently blocks file writes, which is correct for repo safety, but it also prevents a useful read-only review workflow.

Proposed Behavior

• When Plan Mode is active, Codex writes the latest plan draft to a private local path, for example under $CODEX_HOME/plans/ or another agent-owned scratch directory.
• The file is never inside the repo unless explicitly requested after leaving Plan Mode.
• Codex shows the file path to the user.
• Updates happen whenever the plan changes.
• The file is clearly marked as temporary/private and not authoritative until emitted as <proposed_plan>.
• No repo-tracked files are changed, so this does not violate Plan Mode’s no-mutation guarantee.

Acceptance Criteria

• User can open the file in a GUI editor of choice and watch changes live.
• The file persists for the planning session.
• It is excluded from git and normal workspace mutation rules.
• It does not contain secrets unless already present in the plan text.
• The final <proposed_plan> remains the official handoff artifact.

Additional information

_No response_