# How to Set Up Codex Skills from Claude Code Commands in ai-berkshire > Easily set up Codex skills from Claude Code commands in ai-berkshire. Clone the repo and run the install script to convert Markdown skills to Codex packages. - Repository: [Xbt Lin/ai-berkshire](https://github.com/xbtlin/ai-berkshire) - Tags: how-to-guide - Published: 2026-07-11 --- **To set up Codex skills from Claude Code commands in ai-berkshire, clone the repository and run [`./scripts/install-codex-skills.sh`](https://github.com/xbtlin/ai-berkshire/blob/main/./scripts/install-codex-skills.sh), which automatically converts the Markdown files in `skills/` into Codex-compatible packages and installs them to `$HOME/.codex/skills`.** The ai-berkshire repository maintains investment-research commands as Claude Code-compatible Markdown files under `skills/`. When you set up Codex skills from these Claude Code commands, the repository's automation scripts generate platform-specific packages and configure your local Codex environment to recognize them. ## Step-by-Step Installation Process ### Clone the Repository Start by cloning the ai-berkshire repository to access the skill definitions and automation scripts. ```bash git clone https://github.com/xbtlin/ai-berkshire.git cd ai-berkshire ``` ### Generate and Install Codex Skills Run the main installation script to convert Claude Code commands into Codex skills. This script calls [`scripts/sync-codex-skills.py`](https://github.com/xbtlin/ai-berkshire/blob/main/scripts/sync-codex-skills.py) internally to parse the Markdown frontmatter and body from `skills/*.md`, then copies the generated packages to your Codex skills directory. ```bash ./scripts/install-codex-skills.sh ``` By default, the script installs skills to `$HOME/.codex/skills`, creating subdirectories like `~/.codex/skills/investment-research/` containing [`SKILL.md`](https://github.com/xbtlin/ai-berkshire/blob/main/SKILL.md) and supporting assets. ### Install Optional Slash-Command Prompts For a Claude Code-like slash command interface (`/prompts:investment-research`), install the optional prompt wrappers. ```bash ./scripts/install-codex-prompts.sh ``` This copies plain-text prompt files from `codex-prompts/` into your Codex configuration, enabling invocation via the `/prompts:` prefix. ### Restart Codex After installation, restart your Codex CLI or reload your IDE's Codex extension to load the newly installed skills. You can then invoke skills by name (e.g., `investment-research`) or via slash prompts. ## Understanding the Sync Architecture The ai-berkshire repository uses a **single source of truth** pattern where `skills/*.md` files serve as the canonical definitions. ### Source Files in `skills/` Each Claude Code command lives as a self-contained Markdown file with YAML frontmatter. For example, [`skills/investment-research.md`](https://github.com/xbtlin/ai-berkshire/blob/main/skills/investment-research.md) contains the command definition, description, and execution logic. ### The Sync Script [`scripts/sync-codex-skills.py`](https://github.com/xbtlin/ai-berkshire/blob/main/scripts/sync-codex-skills.py) traverses the `skills/` directory and generates Codex-compatible structures under `codex-skills//SKILL.md`. The script handles: - Parsing Markdown frontmatter (name, description) - Converting body content to Codex skill format - Copying referenced assets and tool scripts ### Tooling Integration Helper scripts in `tools/` (such as [`financial_rigor.py`](https://github.com/xbtlin/ai-berkshire/blob/main/financial_rigor.py)) support skill execution. The installation script automatically marks these as executable (`chmod +x`) during the install process, ensuring Codex can invoke them without additional setup. ## Adding Custom Commands To create a new command available in both Claude Code and Codex: 1. Create a new Markdown file in `skills/`: ```bash cat > skills/my-analysis.md <<'EOF' --- name: my-analysis description: Runs custom financial analysis --- # My Analysis This skill performs automated SEC filing analysis. **Usage** ```text my-analysis ``` EOF ``` 2. Regenerate and reinstall: ```bash ./scripts/install-codex-skills.sh ``` 3. Invoke in Codex: ```text my-analysis AAPL ``` ## Code Examples ### Full Setup Workflow ```bash # Clone repository git clone https://github.com/xbtlin/ai-berkshire.git cd ai-berkshire # Install Codex skills and prompts ./scripts/install-codex-skills.sh ./scripts/install-codex-prompts.sh # Verify installation ls ~/.codex/skills/ ``` ### Updating Skills After Changes When you modify files in `skills/`, you must rerun the sync process to update Codex: ```bash # Edit the source vim skills/investment-research.md # Sync changes ./scripts/install-codex-skills.sh ``` ### Using Slash Prompts If you installed the optional prompts, access them via: ```text /prompts:investment-research Tesla ``` This forwards to the underlying `investment-research` skill with the provided argument. ## Summary - **Source of truth**: The `skills/` directory contains canonical Claude Code command definitions in Markdown format. - **Generation**: [`scripts/sync-codex-skills.py`](https://github.com/xbtlin/ai-berkshire/blob/main/scripts/sync-codex-skills.py) converts these Markdown files into Codex-compatible skill packages. - **Installation**: [`scripts/install-codex-skills.sh`](https://github.com/xbtlin/ai-berkshire/blob/main/scripts/install-codex-skills.sh) handles both generation and installation to `$HOME/.codex/skills`. - **Optional UI**: [`scripts/install-codex-prompts.sh`](https://github.com/xbtlin/ai-berkshire/blob/main/scripts/install-codex-prompts.sh) enables slash-command syntax similar to Claude Code. - **Synchronization**: Always rerun the install script after editing `skills/*.md` to keep Codex updated. ## Frequently Asked Questions ### What is the difference between Claude Code commands and Codex skills? Claude Code commands are defined as Markdown files in `skills/` with specific frontmatter and instructions. Codex skills are the same logical commands packaged into a directory structure (`codex-skills//SKILL.md`) that the Codex CLI recognizes. The [`scripts/sync-codex-skills.py`](https://github.com/xbtlin/ai-berkshire/blob/main/scripts/sync-codex-skills.py) file bridges these formats automatically. ### Do I need to reinstall Codex skills after editing the Markdown files? Yes. The `skills/` directory is the canonical source, and changes are not automatically synced to Codex. You must run [`./scripts/install-codex-skills.sh`](https://github.com/xbtlin/ai-berkshire/blob/main/./scripts/install-codex-skills.sh) after any modification to `skills/*.md` to regenerate the Codex packages and copy them to `$HOME/.codex/skills`. ### Where are the generated Codex skills stored locally? By default, the installation script copies generated skills to `$HOME/.codex/skills/` (or `$CODEX_HOME/skills` if that environment variable is set). Each skill appears as a subdirectory containing [`SKILL.md`](https://github.com/xbtlin/ai-berkshire/blob/main/SKILL.md) and any supporting tool scripts from the `tools/` directory. ### How do I add a new command to both Claude Code and Codex? Create a new Markdown file in `skills/` with the appropriate frontmatter (name and description) and command body. After saving, run [`./scripts/install-codex-skills.sh`](https://github.com/xbtlin/ai-berkshire/blob/main/./scripts/install-codex-skills.sh). The new command becomes available immediately in Codex after restart, and will work in Claude Code if you have the repository mounted as a project-specific skill.