---
title: Plugin
slug: docs/plugin
description: Install the Back4app plugin to give Claude Code, Cursor, Codex, GitHub Copilot, Gemini CLI, Grok Build, Kimi Code and Antigravity the Back4app MCP server and the Web Deployment skill.
image: https://cdn.images.archbee.com/yD3zCY-NNBBIfd0uqcfR5/cqkKQ-AuNt0EKKv1IVp_x_plugin.png
createdAt: 2026-11-03T17:55:15.220Z
---

The Back4app plugin gives AI agents the [Back4app MCP server](docId\:Hsedc-08kvkSi2ff-aqcr) and the Web Deployment skill in one install. The skill teaches the agent when to deploy to Back4app, how to prepare the code and what to give back to you. The MCP server does the work.

## Supported tools

| Tool                                | Status    |
| ----------------------------------- | --------- |
| Claude Code                         | Supported |
| Claude (claude.ai, desktop, Cowork) | Supported |
| Cursor                              | Supported |
| OpenAI Codex                        | Supported |
| GitHub Copilot CLI and VS Code      | Supported |
| Gemini CLI                          | Supported |
| Grok Build                          | Supported |
| Kimi Code                           | Supported |
| Antigravity                         | Supported |

## Install

```bash
npx plugins add back4app/back4app-plugin
```

That's it. For Gemini CLI:

```bash
gemini extensions install https://github.com/back4app/back4app-plugin
```

To use the MCP server without the plugin, see [Back4app MCP](docId\:Hsedc-08kvkSi2ff-aqcr).

## What it does

Ask your agent to deploy, and it:

1. Sends your folder of code to Back4app, which builds it with its Dockerfile, or detects the language when there is none.
2. Runs it in a container and follows the build until the application is live.
3. Gives you the public HTTPS address.

After that, the agent can read build and runtime logs, deploy new versions, set environment variables and roll back. Changes to a live application are shown to you as a summary first and run only after you agree.

## No account needed to start

With no Back4app account connected, the agent deploys on a temporary account:

- It lasts 24 hours and holds one application on the Free plan.
- The agent gives you a **claim link**. Open it and sign in, or sign up for free, to keep the application. Otherwise it is deleted at the deadline.
- On a temporary account the build uses a buildpack, not a Dockerfile. Once claimed, the application builds from its Dockerfile.

:::hint{type="info"}
To deploy to your own account instead, ask the agent to sign in to Back4app.
:::

## Before you deploy

- The application must answer HTTP on the port in the `PORT` environment variable, or its health check fails. A bot or a worker with no web server needs a small one on `PORT`, for example one that answers `200` on `/`.
- Leave out `.env` files and secrets. Set them as environment variables of the application.
- Leave out dependencies and build output (`node_modules`, `.venv`, `dist`): the build installs them.

## What's inside

| Component  | Name                      | What it does                                                                                                                                                          |
| ---------- | ------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| MCP server | `back4app`                | Connects to `https://mcp.back4app.com/mcp`. See [tools](docId\:eoaptfF1m9oOmZuDw8bgI).                                                                                |
| Skill      | `back4app-web-deployment` | Tells the agent when to use Back4app, how to deploy (through the MCP server, or the Back4app CLI when the server isn't connected) and what to check before and after. |

Source: [github.com/back4app/back4app-plugin](https://github.com/back4app/back4app-plugin) (MIT).

## Privacy

The plugin talks only to Back4app:

- **MCP server** (`https://mcp.back4app.com/mcp`): the code and settings your agent deploys, and requests for logs.
- **Back4app CLI** (`npx @back4app/cli`), used only when the MCP server isn't connected: it sends the folder to Back4app and leaves out `.git`, `node_modules`, `.venv` and `.env` files.

Your code, environment variables and logs stay on Back4app while the application exists. A temporary account and its application are deleted 24 hours after creation unless you claim them. See the [privacy policy](https://www.back4app.com/privacy.pdf) and [terms](https://www.back4app.com/terms-of-service.pdf).

## Troubleshooting

- **The deployment fails with "Health check failed on port …".** The application doesn't answer HTTP on `PORT`. Make it listen on `process.env.PORT` (or your language's equivalent), or add a small web server to a bot or worker.
- **The agent can't reach Back4app.** Some agents run code in a sandbox with no network access. Connect the MCP server and the agent deploys through it instead.
- **The temporary account ended.** Ask the agent to deploy again, or sign in to your Back4app account.