Skip to main content
Plan mode is a read-only mode for research. While it’s on, the model can read, search, and fetch, but it can’t edit files, write files, or run shell commands. Use it when you want the model to study the code and propose an approach before anything changes.

​
Turn plan mode on and off

There are three ways in and out:
  • Press Shift+Tab in the prompt to toggle plan mode.
  • Type /plan to turn it on. The model can call exit_plan_mode to turn it off when it’s ready to implement.
  • The model can turn it on itself by calling the enter_plan_mode tool.
/plan isn’t listed in /help, but it works. To move the toggle to another key, bind the toggle_plan_mode action in [keybindings]. While plan mode is on, PLAN appears on the left of the second row below the prompt box. Each time the mode changes, o4 tells the model which tools it gained or lost. A typical flow:
  1. Press Shift+Tab.
  2. Ask for a plan, for example:
  3. Read the plan, ask questions, and ask for changes.
  4. Press Shift+Tab again, or tell the model to go ahead. The model calls exit_plan_mode and gets its full tool set back.

​
What the model can use in plan mode

Plan mode limits the model to this fixed list of tools: Every other tool is hidden from the model, and a call to one fails with “Tool ’…’ is blocked in plan mode”. That covers write, edit, bash, the agent and campaign tools, MCP tools, and the plan_* tools described below.
Plan mode is separate from your approval mode. Approvals still apply to the tools that plan mode allows, and switching plan mode on or off doesn’t change your approval mode.

​
The Plan approval mode

o4 also has an approval mode named Plan. It’s one of the options for --permission-mode (ask, accept-edits, plan, review, auto, bypass), and Alt+A cycles through the approval modes in a session. In the Plan approval mode, o4 denies every tool call that would normally need your approval: edits, writes, shell commands, web fetches, and so on. Tools that never ask, such as read, grep, and glob, still run. Unlike plan mode, the model still sees its full tool list. It finds out a tool is off limits only when a call is denied. Start a read-only session from the command line:
For the full list of approval modes, see permissions.

​
Structured plans

Outside plan mode, the model has tools for keeping a multi-step plan on disk: Plans are JSON files in .o4/plans/ in your project. A plan’s status is one of draft, approved, executing, completed, or failed. A step’s status is one of pending, in_progress, completed, failed, or skipped. plan_create and plan_modify ask for approval once per session in the default approval mode. plan_status never asks. checkpoint_create asks once, and checkpoint_restore asks every time. The checkpoint tools need a git repository. checkpoint_restore overwrites tracked files with their content at the tag. It refuses to run while you have uncommitted changes, including untracked files, unless the model passes force, which discards those changes.
Read the approval prompt before you allow checkpoint_restore, and check whether it uses force. To undo the model’s file edits, you can also use undo and rewind.

​
Approving a plan

When the model creates a plan, the tool result ends with “Plan saved. Awaiting user approval.” and the model waits for your answer. There’s no approval dialog: you approve by replying, for example Looks good, go ahead or Do step 2 before step 1. Replying doesn’t change the plan’s status on disk. The plan stays a draft, and its steps stay pending: in o4 0.2.74, none of the model’s tools or your commands mark a plan approved, executing, or completed, or mark a step done. plan_status shows the steps, but its progress doesn’t move. Track the model’s progress with its todo list instead.

​
The plan status row

o4 can show a plan’s progress in the status row while the model is idle, for example Plan 2/5 · Add the refresh endpoint: the number of steps done, the total, and the current step. After each turn, o4 reloads the row from .o4/plans/ and shows only the newest plan marked approved or executing, so a draft plan leaves the row after the next turn. To hide the row, run:
/plan dismiss and /plan close do the same. They only hide the row; the plan file stays as it is.

​
Plans across sessions

Each plan is linked to the session that created it. When you resume that session with o4 resume, o4 restores its linked plan, shows it in the status row, and asks Continue or Abandon. Abandon marks the plan as failed and clears the row. While the plan isn’t completed, o4 also gives the model a short summary of the plan and its steps on every turn of the resumed session. When you start a new session, o4 asks the same question only for a plan marked approved or executing. Because plans the model creates stay drafts, this doesn’t happen for them in 0.2.74. To keep a restored plan without being asked, set auto_approve_plans in .o4/config.toml or ~/.o4/config.toml:
  • Subagents: the built-in Plan subagent designs a plan in its own context.
  • Todos and background tasks: a lighter checklist the model keeps while it works.
  • Goals: keep the model working toward one objective.