Awesome-omni-skill openai-codex

OpenAI Codex CLI usage patterns, configuration, sandboxing, and best practices for AI-assisted development.

install
source · Clone the upstream repo
git clone https://github.com/diegosouzapw/awesome-omni-skill
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/diegosouzapw/awesome-omni-skill "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/data-ai/openai-codex-majiayu000" ~/.claude/skills/diegosouzapw-awesome-omni-skill-openai-codex && rm -rf "$T"
manifest: skills/data-ai/openai-codex-majiayu000/SKILL.md
source content

OpenAI Codex CLI Development

Source: https://github.com/openai/codex

Codex CLI is OpenAI's AI-powered coding agent that runs locally. This skill provides quick reference for effective usage, configuration, and integration.

Best Practices

Getting Started

  • Install via npm:
    npm install -g @openai/codex
    or
    brew install --cask codex
  • Authenticate with ChatGPT - Sign in with your ChatGPT Plus/Pro/Team account
  • Create an AGENTS.md in project roots with project-specific context
  • Use trusted directories to grant file system access

Effective Usage

  • Be specific with requests - "Refactor Dashboard to React Hooks" beats "fix code"
  • Use resume for long tasks -
    codex resume --last
    continues previous sessions
  • Leverage non-interactive mode -
    codex exec "..."
    for automation

Model Selection

Codex uses GPT-4o by default. Override with

--model
:

codex --model gpt-4o          # Default, balanced
codex --model gpt-4o-mini     # Faster, cheaper
codex --model o1-preview      # Advanced reasoning

Configuration

Configuration lives in

~/.codex/config.toml
:

[model]
name = "gpt-4o"

[sandbox]
enabled = true
permissions = ["read", "write", "execute"]

[mcp_servers]
my-server = { command = "node", args = ["./server.js"] }

AGENTS.md Files

Create project context files:

<!-- AGENTS.md -->
# Project Context

This is a React TypeScript project using:
- Vite for bundling
- Tailwind CSS for styling
- React Query for data fetching

## Conventions
- Use functional components with hooks
- Place components in src/components/
- Run `npm test` before committing

Sandbox & Security

  • Sandbox mode restricts file system and network access
  • Execpolicy defines rules for allowed commands
  • Approval modes:
    suggest
    (default),
    auto-edit
    ,
    full-auto
# Run with auto-approval for safe commands
codex --approval-mode auto-edit

# Strict sandbox mode
codex --sandbox

Non-Interactive Mode

Use

codex exec
for automation and CI/CD:

# Single command
codex exec "fix lint errors in src/"

# With specific model
codex exec -m gpt-4o-mini "add TypeScript types to utils/"

# JSON output for scripting
codex exec --json "list all TODO comments"

Quick Reference

Common Commands

# Interactive session
codex

# With initial prompt
codex "explain this codebase"

# Non-interactive
codex exec "fix the bug in auth.ts"

# Resume previous session
codex resume --last
codex resume <SESSION_ID>

# Show status
codex status

Slash Commands

CommandPurpose
/help
Show available commands
/clear
Clear conversation
/status
Show session info
/compact
Compress context
/model
Change model
/bug
Report a bug

Keyboard Shortcuts

ShortcutAction
Ctrl+C
Cancel operation
Ctrl+D
Exit CLI
Ctrl+L
Clear screen
Enter
Send message
Shift+Enter
New line

Environment Variables

OPENAI_API_KEY         # API key (if using API billing)
CODEX_MODEL            # Default model
CODEX_SANDBOX          # Enable sandbox (true/false)
CODEX_HOME             # Config directory (~/.codex)

Documentation Index

Detailed documentation synced from the official GitHub repository.

Getting Started

ResourceWhen to Consult
readme.mdOverview, installation, quickstart
getting-started.mdCLI usage, tips, example prompts
install.mdInstallation options
authentication.mdAuth methods, API keys, headless login

Configuration

ResourceWhen to Consult
config.mdFull configuration reference
example-config.mdExample configurations
agents-md.mdRoot AGENTS.md file
agents-md-guide.mdWriting effective AGENTS.md

Security & Sandboxing

ResourceWhen to Consult
sandbox.mdSandbox mode, permissions
execpolicy.mdCommand execution policies
platform-sandboxing.mdPlatform-specific sandboxing
windows-sandbox.mdWindows sandbox security
zero-data-retention.mdZDR mode

Features

ResourceWhen to Consult
exec.mdNon-interactive mode
prompts.mdCustom prompts
skills.mdCodex skills
slash-commands.mdSlash commands
advanced.mdMCP, tracing, advanced features

Reference

ResourceWhen to Consult
faq.mdFrequently asked questions
changelog.mdVersion history
contributing.mdContributing guidelines
sdk/typescript.mdTypeScript SDK

Syncing Documentation

Resources are synced from the official OpenAI Codex GitHub repository:

cd skills/openai-codex
bun run scripts/sync-docs.ts