# Install Codex Plugin

> Compatibility shim for Codex installs. Use when a developer asks to install, update, enable, reinstall, remove, or verify the Understudy Codex plugin - "install Understudy in Codex", "add the Codex plugin", "make Codex see the skills". Route to install-agent-adapter with platform codex.

- **Type:** Skill
- **Install:** `agentstack add skill-understudylabs-understudy-agent-tools-install-codex-plugin`
- **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior
- **Seller:** [understudylabs](https://agentstack.voostack.com/s/understudylabs)
- **Installs:** 0
- **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills)
- **Latest version:** 0.1.0
- **License:** MIT
- **Upstream author:** [understudylabs](https://github.com/understudylabs)
- **Source:** https://github.com/understudylabs/understudy-agent-tools/tree/main/skills/install-codex-plugin

## Install

```sh
agentstack add skill-understudylabs-understudy-agent-tools-install-codex-plugin
```

Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent.

## About

# Install the Understudy Codex plugin

This skill is a compatibility shim. The consolidated setup surface is
[`install-agent-adapter`](../install-agent-adapter/SKILL.md).

## Procedure

Load `install-agent-adapter` and run it with platform `codex`.

Use its [`reference.md`](../install-agent-adapter/reference.md#codex) for the
current marketplace registration:

```bash
codex plugin marketplace add "$REPO"
```

Activation is in Codex:

```text
/plugins
```

Choose `understudy-skills`, install or enable `understudy`, then ask:

```text
Use the Understudy onboarding skill for this project.
```

## Safety Gates

Local-first and free: registering the Codex marketplace only makes local skills
available. It must not authenticate, upload data, inspect secret values, download
model weights, start hosted jobs, or make provider calls.

- Do not claim the plugin is installed when only the marketplace is registered.
- Do not edit `~/.codex/config.toml` by hand unless the user explicitly asks.
- Do not copy or fork skill content for Codex.

## Resolve CLI

No Understudy CLI command is required. Use `codex plugin marketplace add` when
available; otherwise show the manual `/plugins` activation path from
`install-agent-adapter/reference.md`.

## Output Standard

End with: that this routed through `install-agent-adapter`; whether the Codex
marketplace was registered/refreshed/shown for manual run; the `/plugins` step;
the next onboarding prompt; and the marketplace removal command.

## Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

- **Author:** [understudylabs](https://github.com/understudylabs)
- **Source:** [understudylabs/understudy-agent-tools](https://github.com/understudylabs/understudy-agent-tools)
- **License:** MIT

Install and usage instructions live in the source repository linked above.

## Pricing

- **Free** — Free

## Security capabilities

Automated source analysis of v0.1.0 — what this tool can access:

- **Network access:** no
- **Filesystem access:** no
- **Shell / process execution:** no
- **Environment & secrets:** no
- **Dynamic code execution:** no

*"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.*


## Versions

- **0.1.0** — security scan: passed — Imported from the upstream source.

## Links

- Listing page: https://agentstack.voostack.com/l/skill-understudylabs-understudy-agent-tools-install-codex-plugin
- Seller: https://agentstack.voostack.com/s/understudylabs
- Browse the marketplace: https://agentstack.voostack.com/browse

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Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.