Plan only updates on the first request of a new conversation; never updates on subsequent requests

What version of Codex is running?

codex-cli 0.34.0

Which model were you using?

gpt-5-high

What platform is your computer?

macOS

What steps can reproduce the bug?

1. Start a new Codex CLI conversation.
2. Send an initial request that should require planning, e.g.

“Build a small Python CLI that fetches top GitHub issues for a repo. Show an updated plan first.”

1. Observe Codex CLI displays an “Updated plan.”
2. Send a follow-up request that materially changes scope, e.g.

“Change it to TypeScript and add unit tests. Update the plan before coding.”

1. Observe that no new “Updated plan” appears.
2. Continue sending requests that would require plan changes; the plan never updates.
3. Start a brand-new conversation and repeat; the first turn shows an updated plan again, then never updates afterward.

What is the expected behavior?

The planner recalculates and displays a fresh “Updated plan” whenever a follow-up request changes scope or constraints.

What do you see instead?

Only the first request of a new conversation shows an “Updated plan.” All subsequent requests in that conversation proceed without any plan update, even when explicitly asked to update the plan.

Additional information

In Codex CLI, only the very first user message in a new conversation triggers the model to compute and display an “Updated plan.” From the second message onward in the same conversation, the plan never updates even when the request clearly changes scope. Starting a brand-new conversation restores plan updates for the first turn only.