Codex CLI 1UP: A Complete Guide for Developers

Codex CLI 1UP is a toolkit designed to enhance the Codex CLI coding agent by equipping it with advanced developer tools and practical templates. This guide provides a full overview of its features, installation process, configuration options, and usage. The content here is based entirely on the official documentation and is intended to help you understand, install, and effectively apply Codex CLI 1UP in your workflow.

1. What Is Codex CLI 1UP?

Codex CLI 1UP is an extension layer for Codex CLI (@openai/codex). Its primary goal is to make the coding agent smarter, safer, and more useful by bundling additional utilities, semantic tools, and configuration presets.

Here is what Codex CLI 1UP includes:

✅ Installs Codex CLI
✅ Adds AST-grep for syntax-aware code refactoring
✅ Adds powerful command-line tools: fd, ripgrep (rg), fzf, jq, yq
✅ Provides AGENTS.md templates (generic, typescript, python, shell)
✅ Provides Codex CLI configuration templates (safe, default, yolo)
✅ Includes difftastic for semantic diffs
✅ Adds shell aliases (cx, cxdiff) for faster workflows

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⚠️ Important Note: This toolkit is designed for advanced users. Incorrect configuration may cause issues on your system. It has been tested on macOS with Homebrew, Node.js 22, and zsh. Other environments are unverified. Backup files are automatically created during overwrites, but use the tool responsibly.

2. Why Use Codex CLI 1UP?

When using Codex CLI, developers often encounter two challenges:

Inaccurate code refactoring: Traditional text search tools (grep) can easily break code by matching the wrong patterns.
Unclear code changes: Standard diff outputs are difficult to interpret when reviewing AI-generated modifications.

Codex CLI 1UP addresses these problems with:

AST-grep: A structure-aware search-and-replace tool that works at the syntax tree level.
difftastic: Human-readable semantic diffs that highlight AI changes more clearly.
AGENTS.md templates: A consistent guide for the agent to correctly use tools like fd, rg, ast-grep, fzf, jq, and yq.
Web search enabled by default: The coding agent can look up information when needed.

In short, Codex CLI 1UP makes the coding agent more reliable and the developer more confident in AI-assisted workflows.

3. Quick Start Guide

To install Codex CLI 1UP:

git clone https://github.com/regenrek/codex-1up
cd codex-1up
./install.sh --yes

# Or use the wrapper:
./bin/codex-1up install --yes

After installation, open a new terminal session to load the updated environment.

4. Common Installation Flags

Codex CLI 1UP installation supports several options:

Flag	Description
`--yes`	Non-interactive mode; accepts default safe options
`--dry-run`	Prints the steps without applying changes
`--skip-confirmation`	Skips interactive prompts (useful in CI)
`–shell auto	zsh	bash	fish`	Defines shell type
`--git-external-diff`	Sets difftastic as Git’s external diff tool
`--vscode EXT_ID`	Installs a VS Code extension (e.g., `openai.codex`)
`--agents-md [PATH]`	Writes an `AGENTS.md` file to a path
`--agents-template T`	Selects an `AGENTS.md` template: default, typescript, python, shell
`--no-vscode`	Skips VS Code extension checks
`–install-node nvm	brew	skip`	Defines how Node.js is installed if missing (default: nvm)

5. What Gets Installed

Codex CLI 1UP equips your environment with the following:

Component	Purpose
@openai/codex	Core coding agent for editing and running code locally
ast-grep	Structure-aware search/replace for safer refactoring
fd	Fast, gitignore-aware file finder
ripgrep (rg)	High-performance text search across codebases
fzf	Fuzzy finder for selecting among multiple matches
jq / yq	JSON and YAML command-line processors
difftastic	Semantic diffs for reviewing AI edits
Shell aliases	`cx` (one-shot Codex), `cxdiff` (semantic diffs)
~/.codex/config.toml	Configuration file with SAFE, DEFAULT, YOLO profiles
AGENTS.md	Per-repository rubric to guide the coding agent

6. Templates and Config Profiles

AGENTS.md Templates

Codex CLI 1UP offers templates tailored to different languages and environments:

Template	Description
default	Generic template suitable for most repositories
typescript	TypeScript/TSX-focused rubric with ast-grep examples
python	Python-focused rubric with notes on ruff, mypy, pytest
shell	Shell scripting rubric with shellcheck, shfmt, bats tips

Configuration Profiles

When installing, you can select a configuration mode:

SAFE: Highly restrictive, prompts on failures, sandboxed environment
DEFAULT: Balanced mode with network access (recommended)
YOLO: Full access, no confirmations, higher risk
NO CHANGES: No ~/.codex/config.toml modifications

7. Next Steps After Installation

Open a new terminal session (or reload your shell rc).
Run codex to sign in and start using the agent.
Inside a repository, try:
```
codex
```
Then enter:
“Plan a refactor for X; then apply and run tests.”

Generate an AGENTS.md file with:

./bin/codex-1up agents --path /path/to/your/repo --template default

8. Global AGENTS.md (Optional)

You can create a global guidance file at ~/.codex/AGENTS.md:

mkdir -p ~/.codex
./bin/codex-1up agents --path ~/.codex

This file will serve as a universal reference across all projects.

9. Git Diff Integration (Optional)

Codex CLI 1UP can configure Git to use difftastic:

git difftool will show syntax-aware diffs.
Falls back to git-delta if difftastic is unavailable.
Skips setup if Git is not installed.

This makes AI-generated code changes easier to review.

10. Upgrade and Uninstall

To upgrade:

cd /path/to/codex-1up
git pull --ff-only
./bin/codex-1up install --yes

To check or uninstall:

./bin/codex-1up doctor
./bin/codex-1up uninstall

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Note: Uninstall does not remove global npm packages. It only cleans up shell aliases and Git configurations.

11. Supported Platforms

macOS (Intel and Apple Silicon, via Homebrew)
Linux (via apt, dnf, pacman, zypper)
Windows (via WSL with Ubuntu)

12. Frequently Asked Questions (FAQ)

{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "What should I do if installation fails?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Check if Node.js 22 is installed and confirm you are using a supported package manager (Homebrew on macOS, apt/dnf on Linux)."
      }
    },
    {
      "@type": "Question",
      "name": "Why is the VS Code extension not installing?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Use the --no-vscode flag to skip extension checks. You can install 'openai.codex' manually from the VS Code marketplace."
      }
    },
    {
      "@type": "Question",
      "name": "How do I fully uninstall Codex CLI 1UP?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "The uninstall command removes aliases and Git config but not global npm packages. To fully uninstall, manually remove @openai/codex and @ast-grep/cli."
      }
    },
    {
      "@type": "Question",
      "name": "Does Codex CLI 1UP support multiple languages?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "Yes. You can choose AGENTS.md templates for TypeScript, Python, Shell, or the default template."
      }
    },
    {
      "@type": "Question",
      "name": "Is YOLO mode safe?",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": "YOLO mode gives full access without confirmations. It carries risks and should only be used in experimental or local environments."
      }
    }
  ]
}

13. Installation Steps (HowTo Schema)

{
  "@context": "https://schema.org",
  "@type": "HowTo",
  "name": "Install Codex CLI 1UP",
  "step": [
    {
      "@type": "HowToStep",
      "text": "Clone the repository",
      "url": "https://github.com/regenrek/codex-1up",
      "image": "./public/banner.png"
    },
    {
      "@type": "HowToStep",
      "text": "Navigate to the directory and run the install script",
      "url": "https://github.com/regenrek/codex-1up"
    },
    {
      "@type": "HowToStep",
      "text": "Open a new terminal session after installation",
      "url": "https://github.com/regenrek/codex-1up"
    },
    {
      "@type": "HowToStep",
      "text": "Run 'codex' and sign in to start using the agent"
    }
  ]
}

14. Summary

Codex CLI 1UP enhances Codex CLI by solving practical developer challenges in code refactoring, semantic diffs, and tool consistency. It gives AI-powered coding assistance a stronger foundation while keeping developers in control.

With structured templates, safer defaults, and advanced utilities, Codex CLI 1UP is not just a toolkit — it is an optimized workflow layer that improves how humans and AI collaborate in coding projects.

Codex CLI 1UP Toolkit: Revolutionizing AI-Assisted Coding with Semantic Refactoring & Workflow Optimization