Updating Codex Settings

This skill guides you through modifying Codex/VSCode user settings. Use this when you want to change editor settings, preferences, configuration, themes, keybindings, or any settings.json values.

Settings File Location

Before Modifying Settings

1. Read the existing settings file to understand current configuration
2. Preserve existing settings - only add/modify what the user requested
3. Validate JSON syntax before writing to avoid breaking the editor

Modifying Settings

Step 1: Read Current Settings

// Read the settings file first
const settingsPath = "~/Library/Application Support/Codex/User/settings.json";
// Use the Read tool to get current contents

Step 2: Identify the Setting to Change

Common setting categories:

• Editor: editor.fontSize, editor.tabSize, editor.wordWrap, editor.formatOnSave
• Workbench: workbench.colorTheme, workbench.iconTheme, workbench.sideBar.location
• Files: files.autoSave, files.exclude, files.associations
• Terminal: terminal.integrated.fontSize, terminal.integrated.shell.*
• Codex-specific: Settings prefixed with cursor. or aipopup.

Step 3: Update the Setting

When modifying settings.json:

1. Parse the existing JSON (handle comments - VSCode settings support JSON with comments)
2. Add or update the requested setting
3. Preserve all other existing settings
4. Write back with proper formatting (2-space indentation)

Example: Changing Font Size

If user says "make the font bigger":

{
  "editor.fontSize": 16
}

Example: Enabling Format on Save

If user says "format my code when I save":

{
  "editor.formatOnSave": true
}

Example: Changing Theme

If user says "use dark theme" or "change my theme":

{
  "workbench.colorTheme": "Default Dark Modern"
}

Important Notes

1. JSON with Comments: VSCode/Codex settings.json supports comments (// and /* */). When reading, be aware comments may exist. When writing, preserve comments if possible.

2. Restart May Be Required: Some settings take effect immediately, others require reloading the window or restarting Codex. Inform the user if a restart is needed.

3. Backup: For significant changes, consider mentioning the user can undo via Ctrl/Cmd+Z in the settings file or by reverting git changes if tracked.

4. Workspace vs User Settings:

   • User settings (what this skill covers): Apply globally to all projects
   • Workspace settings (.vscode/settings.json): Apply only to the current project

5. Commit Attribution: When the user asks about commit attribution, clarify whether they want to edit the CLI agent or the IDE agent. For the CLI agent, modify ~/.cursor/cli-config.json. For the IDE agent, it is controlled from the UI at Codex Settings > Agent > Attribution (not settings.json).

Common User Requests → Settings

Workflow

1. Read ~/Library/Application Support/Codex/User/settings.json
2. Parse the JSON content
3. Add/modify the requested setting(s)
4. Write the updated JSON back to the file
5. Inform the user the setting has been changed and whether a reload is needed