Install agent skills and plugins in Claude, Codex, and Cursor

Use plugin marketplaces with coding agents. Upload a skill ZIP when you work in ChatGPT or Claude.ai. This guide covers both paths and how to use what you install.

Choose the installation path for your app

Install a plugin when you use a coding agent. Upload a ZIP when you use Skills in ChatGPT or Claude.ai.

Claude Code, Codex, Cursor, and Gemini CLI

Add the marketplace where supported, or install a local Gemini extension.

Install coding-agent plugins

ChatGPT and Claude.ai

Download one skill as a ZIP, then upload it through the Skills interface.

Upload a skill ZIP

Add this marketplace to Claude Code

Claude Code uses the same configured marketplaces in the terminal and desktop app for local sessions.

From the terminal, add the marketplace once, then install each plugin by name.

claude plugin marketplace add fcakyon/claude-codex-settings
claude plugin install simplify@claude-settings

In Claude Code desktop, select + beside the prompt, then Plugins and Add plugin. Choose a plugin from the configured marketplace.

Run /reload-plugins after an install in an open session. New sessions load installed plugins automatically.

Read the official Claude Code plugin guide

Add this marketplace to OpenAI Codex

Codex supports this marketplace in the terminal and the Codex desktop app. The Codex IDE extension doesn’t support plugins.

From the terminal, add the marketplace once, then install each plugin by name.

codex plugin marketplace add fcakyon/claude-codex-settings
codex plugin add simplify@claude-settings

Enter /plugins in Codex CLI to browse configured marketplaces interactively. Start a new session after installing a plugin.

In the Codex desktop app, open Plugins, find the plugin, and select Install. Start a new task before you use its skills or tools.

Read the official OpenAI plugin guide

Add this marketplace to Cursor

Cursor installs personal plugins interactively. User-scope plugins work in the Cursor app and Cursor Agent CLI.

From the terminal, add the repository and start Cursor Agent. Enter /plugin to choose and install a plugin.

cursor-agent plugin marketplace add https://github.com/fcakyon/claude-codex-settings
cursor-agent

In the Cursor app, open Customize, find the plugin, and select Install. Choose user or project scope when prompted.

The marketplace command only adds the catalog.

Read the official Cursor plugin guide

Install a local extension in Gemini CLI

Gemini CLI installs extensions from local plugin folders. Clone the repository, then run the extension command from its root.

git clone https://github.com/fcakyon/claude-codex-settings.git
cd claude-codex-settings
gemini extensions install --path ./plugins/simplify

Replace simplify with the plugin you want. Start a new Gemini CLI session after installation.

Read the official Gemini CLI extension reference

Use an installed plugin in a new session

Start a new session so the agent loads the plugin. Describe the task or name the skill in your prompt.

Use the simplify skill to review my staged diff.
Use the humanize skill to revise this README.

Some plugins also add slash commands. Open the plugin catalog to see each plugin’s components and install commands.

Choose and review a skill

Open the source before uploading code from any publisher. Check SKILL.md, scripts, references, and external tool requirements.

Browse all skill downloads

Upload a skill to ChatGPT

Personal Skills are available on eligible ChatGPT plans. Workspace administrators can control skill uploads.

Live ChatGPT interface showing the Skills page, upload menu, and ZIP upload screen — Current ChatGPT Skills upload flow, recorded from the live interface.

Open chatgpt.com/skills
Select the Skills tab
Select +, then Upload a skill
Choose the downloaded ZIP and wait for the security check
Run a prompt that matches the skill description

Read the official OpenAI Skills guide

Upload a skill to Claude.ai

Custom skills are available on supported Claude plans with code execution enabled.

Live Claude interface showing the Add menu and ZIP upload screen — Current Claude Skills upload flow, recorded from the live interface.

Open Customize, then Skills
Select Add, then Upload skill
Choose the downloaded ZIP
Select Save and wait for the security scan
Run a prompt that matches the skill description

Read the official Claude Skills guide

Keep the named folder inside the ZIP

Claude requires the archive to contain the named skill directory. Every release asset on this site follows that structure.

skill-name.zip
└── skill-name/
    ├── SKILL.md
    ├── scripts/
    └── references/