How do I install skills in Codex CLI?

01

What is a Codex skill?

A Codex skill is a reusable set of instructions for one kind of job. Think of it like an office checklist that Codex can keep on hand. A skill may also include reference material, templates, or small scripts, but you do not need to understand those parts to install a curated skill.

A prompt and a skill are related, but they are not the same. A prompt is an instruction you give the AI for a task. A skill packages a workflow so Codex can use it again. On archiPrompt, every listing card says whether the product is a Prompt system, Agent skill, Workflow, Template bundle, or Collection.

• Source: Build skills

02

What do you need before you start?

This guide starts after Codex CLI is installed and open. Codex CLI is the command-line version of Codex, which you use in a terminal window. Once Codex opens, you type messages into the Codex conversation shown in that window.

For your first attempt, use OpenAI's curated Linear example and an empty practice folder. You do not need a drawing, model, project repository, GitHub account, or client file. The goal is simply to learn where the instruction goes and how to check that it worked.

03

How do you install your first skill?

First, open Codex CLI. Wait until you can see the Codex conversation and can type a message. Then enter the line below exactly as shown and press Return or Enter. OpenAI uses Linear as its official curated installation example.

The line begins with a dollar sign because you are asking Codex to use its built-in Skill Installer. Do not enter this line before Codex opens. If your window is showing only a normal computer prompt, start Codex first.

• — Open Codex CLI and wait for the conversation
• — Type `$skill-installer linear`
• — Press Return or Enter
• — Read the confirmation before accepting any requested access
• — Wait for Codex to say the installation is finished

$skill-installer linear

• Source: Build skills

04

How do you check that the skill installed?

After Codex reports that the installation is complete, enter `/skills`. Codex should show a list or selector containing Linear. You can also type `$` in Codex to open the skill selector and look for the same name.

For a low-risk first check, select the skill and ask it to explain what it can help with. Tell it not to open, create, or change files. Seeing the correct skill in the selector is the important installation check; connecting a Linear account is a different task.

• — Linear appears in the `/skills` list or `$` selector
• — Codex can select the skill by name
• — Your first test does not use confidential project information
• — No file or external-service access is approved unless you understand why it is needed

/skills

• Source: Build skills

05

What if the skill does not appear?

If Linear is missing, first make sure the installer said it finished. Then check the spelling and enter `/skills` again. OpenAI says Codex normally detects newly installed skills automatically; if it does not, close Codex, open it again, and repeat the check.

If the skill is still missing after one restart, stop there. Do not start copying folders or running deletion commands from an unfamiliar guide. Manual installation, personal and project skill locations, and deeper troubleshooting need their own step-by-step articles.

• — Confirm the installer completed
• — Check the skill name
• — Enter `/skills` again
• — Restart Codex once
• — Use a dedicated troubleshooting guide if it is still missing

• Source: Build skills

06

Which archiPrompt skills show the AEC use case?

To see what an AEC-focused reusable workflow looks like, open the Drawing Set Coordination Review and BIM Model QA Checklist cards below. Both are published archiPrompt Agent skills. Their listing pages state their inputs, outputs, limitations, supported tools, and human-review steps.

Use them as examples of how skills can support architecture work. Their current listings do not claim Codex compatibility, so do not type their names into Skill Installer. archiPrompt will only describe a listing as Codex-compatible after that exact product and installation route have been tested.

• — Drawing Set Coordination Review — a multidisciplinary PDF review workflow
• — BIM Model QA Checklist — a workflow for checking exported BIM information
• — Read the asset type and compatibility shown on each listing before using it with any AI tool

07

What should you learn next?

You now have the complete beginner route for one curated skill: install it inside Codex, check it with `/skills`, and restart once if it is missing. The older version of this guide also covered custom folders, team sharing, GitHub sources, configuration files, plugins, disabling, and removal. Those topics made the basic task much harder to follow, so they have been separated into focused follow-up guides.

Your next step is to repeat this process only with a skill whose publisher and purpose you understand. Before using any skill on real work, read its listing or source, check what it can access, and test it with non-confidential material.

• — How do I install Codex CLI?
• — How do I install a custom Codex skill from GitHub?
• — Where are personal and project Codex skills stored?
• — Why is my Codex skill not showing?
• — How do I disable or remove one Codex skill safely?