Plan Mode with the latest custom prompts capability in Codex CLI

[Meowzz95]

We've all been waiting for Plan Mode but now with the latest custom prompt, we can somehow achieve this. Here's the "custom prompt" file you need to put in your codex folder ~/.codex/prompts/plan.md

---
description: Plan according to the user's request, without starting the implementation.
---

$INSTRUCTIONS

Follow the instructions given by the user. You have to come up with a plan first, User will review the plan and let you know what to change or ok to proceed. You can record the plan using your own way like using the todo tool, but in additional, give user a text version of the plan to read. Only start implementing after getting the approval.

Then just /plan in codex and you get a nice auto completed placeholder

[Meowzz95]

Although there’s no built-in way to prevent Codex from starting implementation, GPT-5’s strong steerability helps ensure it begins only after approval!