# Apply Technique: OpenAI Codex CLI: March 2026 Update with Experimental Code Mode, Plugins, and Streaming I/O
## What This Is
OpenAI's command-line coding assistant, Codex CLI, has been significantly updated to run complex tasks more autonomously. It now operates natively on Windows, features a plugin marketplace for adding new capabilities, and can stream live output from running processes, improving monitoring of tasks like server startups or builds.
Source: https://releasebot.io/updates/openai/codex
## 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://releasebot.io/updates/openai/codex) 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
- Execute `npm i -g @openai/codex@latest` in the terminal to install or update to the latest version of the OpenAI Codex CLI.
- Run `codex plugins --list-remote` to explore the new plugin marketplace and review the metadata for available tools like the web search plugin.
- Test the new streaming I/O and terminal integration by creating a test Express.js server and instructing the agent to start it, then asking '`Is the server running successfully? Check the terminal output for confirmation.`'
## Reference Implementation
```
npm i -g @openai/codex@latest
```
## 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