## Summary
Adds the missing `xhigh` reasoning level everywhere it should have been
documented, and makes clear it only works with `gpt-5.1-codex-max`.
## Changes
* `docs/config.md`
* Add `xhigh` to the official list of reasoning levels with a note that
`xhigh` is exclusive to Codex Max.
* `docs/example-config.md`
* Update the example comment adding `xhigh` as a valid option but only
for Codex Max.
* `docs/faq.md`
* Update the model recommendation to `GPT-5.1 Codex Max`.
* Mention that users can choose `high` or the newly documented `xhigh`
level when using Codex Max.
Update FAQ, improve general structure for config, add more links across
the sections in the documentation, remove out of date and duplicate
content and better explain certain concepts such as approvals and
sandboxing.
Apparently we were not running our `pnpm run prettier` check in CI, so
many files that were covered by the existing Prettier check were not
well-formatted.
This updates CI and formats the files.
This PR cleans up the monolithic README by breaking it into a set
navigable pages under docs/ (install, getting started, configuration,
authentication, sandboxing and approvals, platform details, FAQ, ZDR,
contributing, license). The top‑level README is now more concise and
intuitive, (with corrected screenshots).
It also consolidates overlapping content from codex-rs/README.md into
the top‑level docs and updates links accordingly. The codex-rs README
remains in place for now as a pointer and for continuity.
Finally, added an extensive config reference table at the bottom of
docs/config.md.
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Co-authored-by: easong-openai <easong@openai.com>
