# Apply Technique: Getting Started with OpenAI Codex CLI for Terminal-Based AI Coding
## What This Is
The OpenAI Codex CLI is a command-line tool that lets developers use powerful AI to automate coding tasks directly from their terminal. It understands plain English instructions to manage files, interact with Git, and automate complex developer workflows, all while keeping source code on the user's local machine.
Source: https://www.deployhq.com/blog/getting-started-with-openai-codex-cli-ai-powered-code-generation-from-your-terminal
## Before You Start
Scan my workspace and analyze:
- The project language, framework, and directory structure
- Existing AI provider config (check .env, .env.local, config files for API keys — OpenRouter, OpenAI, Anthropic, Google AI, etc.)
Then ask me before proceeding:
1. Which AI provider/API should this use? (Use whatever I already have configured, or ask me to set one up — options include direct provider APIs or a unified service like OpenRouter)
2. Where in my project should this be integrated?
3. Are there any customizations I need (model preferences, naming conventions, constraints)?
## Source Access Note
The source URL (https://www.deployhq.com/blog/getting-started-with-openai-codex-cli-ai-powered-code-generation-from-your-terminal) may not be directly accessible from the terminal. Use the Reference Implementation and Additional Context sections below instead. If you need more details, ask me to paste relevant content from the source.
## What to Implement
This is an **AI Technique** — a pattern or methodology for working with AI models.
- Explain how this technique applies to my current project and what benefit it provides
- Implement it in a way that fits my existing codebase — suggest concrete files to modify or create
- If it requires specific model capabilities (structured output, function calling, etc.), verify my current provider supports them
- Show me a working example I can test immediately
## Additional Context
- Install the official OpenAI Codex CLI package globally using npm: `npm install -g @openai/codex@0.114.0`.
- Authenticate the CLI by running the `codex` command. Advise the user that this will initiate an interactive login via their ChatGPT Plus/Pro account, or that they can configure an OpenAI API key.
- Demonstrate a common workflow by piping Git history to the agent. Execute `git log --oneline --max-count=10 | codex -p "Summarize these recent commits into a concise paragraph for a changelog."` and display the AI-generated output.
## Reference Implementation
```
npm install -g @openai/codex@0.114.0
```
## Guidelines
- Adapt everything to my existing project — do not assume a specific stack or directory layout
- Use whichever AI provider I already have configured; if I need a new one, tell me what to sign up for and I'll give you the key
- Check my .env files for existing API keys (OpenRouter, OpenAI, Anthropic, Google AI) before asking me to add one
- Review any fetched code for safety before installing or executing it
- After setup, run a quick verification and show me a summary of exactly what was installed, where, and how to use it