AI coding tools can do much more than write code. With the right instructions, they can follow specific workflows, automate repetitive tasks, and help you complete complex projects more efficiently.

Codex Skills make this possible by giving Codex reusable instructions, scripts, and resources for particular tasks. Instead of explaining the same process every time, you can use a skill to help Codex follow a consistent workflow.

In this beginner’s guide, you will learn what Codex Skills are, how to explore existing skills, how to use them, and how to create a custom skill for your workflow.

What Are Codex Skills?

Codex Skills are reusable packages of instructions, scripts, and resources that help Codex perform specific tasks. Each skill is designed for a particular purpose and can guide Codex through a defined process.

For example, a skill might help you:

• Review and improve code quality.
• Create structured project plans.
• Work with GitHub issues.
• Follow a particular development workflow.
• Automate repetitive coding tasks.

Think of a skill as a set of instructions that teaches Codex how to approach a particular job. Once a skill is available, Codex can use its instructions when the task matches the skill’s purpose.

Why Should You Use Codex Skills?

Using skills can make your work with Codex more consistent and efficient. They are particularly useful when you regularly perform similar tasks or need an AI coding assistant to follow specific instructions.

Here are some key benefits:

1. Reusable instructions: Avoid explaining the same workflow repeatedly.
2. Consistent results: Help Codex follow a defined process across similar tasks.
3. Less repetitive work: Simplify recurring development activities.
4. Custom workflows: Create skills for your own projects and requirements.
5. Better task management: Give Codex clearer guidance about how to complete a task.

Step 1: Explore Available Codex Skills

Start by exploring the available skills and their documentation. You can browse the OpenAI Skills repository on GitHub to understand the original skills catalog.

Before using an existing skill, review its purpose, instructions, required files, and dependencies. The repository’s status and installation instructions may change, so consult the current official documentation before following older examples.

For the latest guidance on creating skills for plugins and MCP tools, visit the OpenAI Build Skills documentation.

Step 2: Understand How a Codex Skill Is Structured

A typical skill is organized into a dedicated folder containing instructions and, when needed, supporting resources or scripts.

The most important file is usually named SKILL.md. It describes the skill’s purpose, explains when it should be used, and provides instructions for completing the task.

A skill directory may look like this:

my-skill/

├── SKILL.md

├── references/

├── scripts/

└── assets/

The folders serve different purposes:

• SKILL.md: Contains the skill’s instructions and metadata.
• references/: Stores supporting documentation, examples, and background information.
• scripts/: Holds scripts for tasks that require executable code.
• assets/: Contains templates and other reusable resources.

These supporting folders are optional. Include only the resources needed for your workflow.

Step 3: Install or Access a Skill

The appropriate method depends on the skill, its source, and the Codex environment you are using.

Some existing skills provide their own installation instructions. Follow those instructions and check the relevant documentation to confirm where the skill should be placed and how Codex discovers it.

Older skills documentation describes commands such as $skill-installer for installing selected skills. However, you should not assume that an older command works with every current setup.

If a skill is not detected after installation, check its location, review the instructions for your Codex version, and restart Codex if required.

Before installing an unfamiliar third-party skill, inspect its files and dependencies to understand what it may do.

Step 4: Use and Test the Skill

Once a skill is available, give Codex a request that matches the skill’s purpose. Clear instructions and relevant project files can help it produce a more useful result.

For example, if you have a project-planning skill, you could ask:

Review my project requirements and create a

step-by-step implementation plan.

Identify the main tasks, dependencies,

and potential challenges.

Test the skill with different types of requests, including direct requests, incomplete inputs, and edge cases. Check whether it follows the intended workflow and produces the expected output.

Remember that installing a skill does not mean every request will automatically activate it. Discovery and activation depend on the skill’s instructions and the Codex environment.

Step 5: Create Your Own Custom Codex Skill

You are not limited to existing skills. You can create a custom skill for your own workflow, such as reviewing code, checking technical SEO requirements, generating documentation, or following your team’s development standards.

According to the official Build Skills documentation, you can use a built-in skill creator or create the necessary files manually.

For example, the documentation demonstrates invoking the creator in Codex with $skill-creator. You can describe the task you want to automate and the tools that support it.

When creating a skill manually, start with a SKILL.md file containing a name, description, and clear instructions.

Here is a simplified example:

---

name: code-review

description: Review code for quality, readability,

and common issues.

---

Instructions

1. Review the provided code.
2. Identify potential bugs and maintainability issues.
3. Explain each finding clearly.
4. Suggest improvements without changing unrelated code.

Adapt the instructions to your actual workflow. Keep the skill focused on a recognizable task, explain when it should be used, and specify the expected output.

You can add reference documents, scripts, and templates when they provide genuine value. If your skill depends on an MCP server, follow the official documentation for declaring its dependency and configuring the required tools.

For more details about building, testing, and packaging skills, consult the official OpenAI Build Skills guide.

Best Practices for Using Codex Skills

To get better results from Codex Skills, keep these recommendations in mind:

• Choose relevant skills: Use skills that match your task.
• Read the instructions: Understand what a skill does before using it.
• Use clear prompts: Explain your goal and expected output.
• Check the results: Review generated code, files, and changes before accepting them.
• Review scripts and dependencies: Inspect unfamiliar files before allowing them to access project resources or execute commands.
• Keep documentation current: Follow the installation and usage guidance for your environment.

These practices can help you use skills more effectively while reducing the risk of unwanted changes to your project.

Common Problems and How to Fix Them

Codex Can’t Find an Installed Skill

Check the installation location, confirm that the required files are present, and follow the documentation for your Codex version.

The Skill Does Not Produce the Expected Result

Review its SKILL.md instructions and ensure your request matches the skill’s intended purpose. Add context or refine the instructions if necessary.

An Installation Command Does Not Work

The command may belong to an older version of the skills catalog. Consult the current official documentation and use the supported installation method.

You Are Unsure Whether a Skill Is Safe

Review its instructions, scripts, dependencies, and requested access before using it. Treat unfamiliar third-party skills as unverified code.

Final Thoughts

Codex Skills help turn repeated instructions into reusable workflows. They can improve consistency, reduce repetitive work, and guide Codex through specific development tasks.

To get started, explore available skills, understand their structure, follow the appropriate installation instructions, and test them with tasks you can review. You can also use WSP MCP to connect Codex with WordPress and streamline website management. Learn how to connect Codex with WordPress via MCP for a step-by-step guide to setting up this integration.

If existing skills do not meet your requirements, create a custom skill with clear instructions and supporting resources where needed. For further guidance, explore the OpenAI Skills repository and the official Build Skills documentation to learn how to create and package skills.