CLI customization

For the complete documentation index, see llms.txt. Markdown versions of documentation pages are available by appending .md to the page URL.

The Codex CLI provides terminal-specific options for how interactive sessions look and how you enter commands and prompts.

Syntax highlighting and themes

The terminal UI (TUI) syntax-highlights fenced Markdown code blocks and file diffs. Run /theme to open the theme picker, preview themes, and save your selection to tui.theme in $CODEX_HOME/config.toml.

To add a custom theme, place a .tmTheme file in $CODEX_HOME/themes, then select it from the theme picker.

Shell completions

Generate a completion script for Bash, the Z shell, Fish, or PowerShell:

codex completion zsh

Load the script from your shell configuration. For the Z shell, add:

eval "$(codex completion zsh)"

If the Z shell reports command not found: compdef, initialize its completion system before loading the Codex completions:

autoload -Uz compinit && compinit
eval "$(codex completion zsh)"

Restart the shell, type codex, and press Tab to verify completion.

Prompt editor

For longer prompts, press Ctrl+G in the composer to open the editor configured by VISUAL, or EDITOR when VISUAL isn't set. Save and close the editor to return the text to the composer before sending it.

For interactive keyboard controls and the full command and option list, see Commands.