Codex CLI Theme Not Applying? Fix It in 5 Steps

/theme returns nothing, the colors don’t change, or the palette looks wrong? Codex CLI theme problems are almost always one of five causes. Here’s how to diagnose and fix each one in order.

1. The theme isn’t installed (most common)

/theme only lists themes that exist in Codex CLI’s theme directory. If you never ran an install script, the list is empty or only shows the default.

Fix: install a palette first:

curl -fsSL https://raw.githubusercontent.com/vufly/bearded-theme-ports/master/scripts/install-codex.sh | sh

Then reopen the prompt and run /theme again — the new palette should appear under its exact name.

2. Stale color cache at startup

Some ports cache colors when Codex CLI starts. After applying a theme, the palette can look wrong until the next launch.

Fix: restart Codex CLI after applying the theme, then re-run /theme with the same name. If the correct palette appears, the cache was the culprit.

3. The theme name doesn’t match

/theme matches theme names exactly. Tokyo Night is not the same as tokyo-night or TokyoNight.

Fix: run /theme with no arguments and copy the exact name from the list, then apply it verbatim.

4. Wrong or partial palette file

A palette copied from a porting script can be incomplete — missing background, foreground or syntax keys. This shows up as mostly-default colors with one or two changes.

Fix: re-run the install script to fetch the complete theme, or use a manager to validate the file:

# Codex Themes CLI validates the palette before applying:
codex-theme validate <name>
codex-theme apply <name>

5. Terminal and CLI out of sync

If the terminal matches but Codex CLI doesn’t (or vice-versa), the two are reading different configs. CLI themes are just palettes — they don’t change your terminal profile.

Fix: export the same palette to both. Codex Themes CLI can write the identical colors to your terminal profile, so one apply syncs both surfaces:

codex-theme export <name> --to-terminal

Still stuck?

Reset to a clean state: uninstall the palette, restart, reinstall, and apply with the exact name. If a specific skin has an issue, browse the Mono & Terminal category for the latest palette variants, or check the CLI themes guide for the full install workflow.