codex/codex-rs/tui/styles.md

Headers, primary, and secondary text

• Headers: Use bold. For markdown with various header levels, leave in the # signs.

• Primary text: Default.

• Secondary text: Use style::secondary_text_style() for shared footer descriptions and status lines. It resolves a readable muted foreground when the terminal palette is known and clears inherited dim/bold modifiers. Other secondary surfaces may still use dim.

• Keyboard hints: Use key_hint span helpers for compact, uniformly bold shortcut labels and readable secondary descriptions. Include +, /, and chord separators in the label's emphasis. The ? shortcut reference uses readable accent-colored keys without bold. Separate composer footer actions with ·.

Foreground colors

• Default: Most of the time, just use the default foreground color. reset can help get it back.
• Active controls and input emphasis: Use style::accent_style() or style::accent_color_on(background) for text on a painted surface.
• Semantic statuses: Use style::status_style(StatusTone); terminal-owned ANSI colors remain the fallback for limited palettes.
• Success and additions: Use ANSI green.
• Errors, failures and deletions: Use ANSI red.
• Codex: Use ANSI magenta.

Avoid

• Avoid unchecked custom foreground colors. Use style::readable_color_on(color, background) for theme-derived text, passing the background actually painted behind it. None means the terminal background; color reduction is included in the contrast check. When the background is unknown, supported theme colors are preserved rather than guessed. Generic code renderers preserve configured syntax foregrounds; diff rendering resolves them against its add/delete fills.
• Avoid ANSI black & white as foreground colors because the default terminal theme color will do a better job. (Use reset if you need to in order to get those.) The exception is if you need contrast rendering over a manually colored background.
• Avoid ANSI blue and yellow because for now the style guide doesn't use them. Prefer a foreground color mentioned above.

(There are some rules to try to catch this in clippy.toml.)

Menu descriptions

• Prefer concise built-in option descriptions and disabled-option explanations without trailing periods.
• When a description needs multiple sentences, keep normal punctuation, including the final period. Do not combine sentences at the expense of clarity.
• Preserve externally supplied descriptions as written.