Token usage spikes too quickly in Codex CLI sessions

I’m seeing unusually fast token consumption in Codex CLI during normal work(~35% of 5h limit; ~600k tokens shown on /quit).

Symptoms

A few short dialogs consumed ~35% of the 5-hour token limit.
After exiting with /quit, the CLI reported ~600k tokens for the session.
This is markedly higher than my typical rate in comparable projects.

Context
The issue became noticeable after Codex Cloud started counting toward our org rate limit and our limits were reset.
Session purpose: pushing test work to improve branch coverage in a Python backend. I pasted my previously written task summary to Codex to proceed.
No errors surfaced; just unusually high token accounting/consumption and frequent limit hits during normal activity.

Minimal repro (as I experience it)

Start a Codex CLI session in the project.
Ask for guidance to increase branch/line coverage in a Python backend (short prompts/replies; mostly text + small snippets).
After a few turns, observe the 5h limit consumption climbing unexpectedly.
Exit with /quit and note the token tally (~600k in my case).

What I expect

Normal short dialogs should not consume ~600k tokens nor ~35% of the 5h limit.
Environment (for convenience; logs also uploaded via /feedback)

Codex CLI: 0.53
Subscription: team
Model: codex-high
Platform: Darwin 25.0.0 arm64 arm
Thread ID: 019a45a2-fca6-7612-b0e7-f82761d7a8cc

Other notes

No special concurrency configuration.
No clear signs of background indexing/retrieval or other activity during idle moments.
Logs were uploaded via /feedback from the CLI; this issue was opened through that link.