Paths/Codex Engineer/Planning with Codex / Plan Decomposition
Break a Request Into Steps
A big request handed to an agent in one go produces a big diff nobody reviewed. Write the plan that breaks it into steps you can check.
Validator
IDLE — checks run live as you type commands; submit when done
01Requirements
live checks- Directory ~/codex/plans exists○
- File ~/codex/plans/plan.yaml exists○
- The plan states the goal and the steps○
- The plan states how each step is verified○
02Walkthrough
4 steps- 01
Create the plans directory
Every plan for a repository lives in the repository.
mkdir -p ~/codex/plans - 02
Write the goal and the scope
One sentence for the goal, and an explicit list of what the change does not touch. The out of scope list is what stops the agent wandering.
echo 'goal: add pagination to the orders list endpoint\nout_of_scope:\n - the export endpoint\n - the database schema' > ~/codex/plans/plan.yaml - 03
Write the steps and the verification
Each step names the files it touches and how you know it worked. A step nobody can verify is a step nobody can review.
echo '\nsteps:\n - name: add the limit and cursor parameters\n files: [src/server/orders/routes.ts]\n verify: the request with a limit returns fewer rows\n - name: add the cursor encoding\n files: [src/server/orders/cursor.ts]\n verify: a unit test round trips a cursor' >> ~/codex/plans/plan.yaml - 04
Verify and submit
cat the plan, then submit for validation.
cat ~/codex/plans/plan.yaml
03Stuck?
0 of 3 revealedTake a hint without losing the lab — each one points at the thing to look at, not at the answer.
04AI Tutor
guides, never solvesTell me what you're stuck on — I'll nudge, not solve. Which requirement are you looking at?
04Notebook
saved locally in this browserlearner@lab — ubuntu:24.04
Session is disposable
↑/↓ recalls commands · Ctrl+Enter submits · type help for the command list