> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mcp-agent.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Deploy and host a ChatGPT App

> Deploy and host your ChatGPT App (MCP server) so anyone can use it.

In this article, we walk through how to deploy your ChatGPT App to the mcp-agent cloud platform to have it readily available for anyone to use.

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## What are ChatGPT Apps?

OpenAI announced the [support for Apps within ChatGPT](https://openai.com/index/introducing-apps-in-chatgpt/). ChatGPT Apps unlock interactive experiences that live inside ChatGPT conversations, allowing applications to respond to natural language with in-chat interfaces (like maps or playlists).

## Guide for deploying your application

### TL;DR

1. **Create an `MCPApp()`** in your python server code
2. **Install** the `mcp-agent` library
3. **Deploy** with the `mcp-agent` CLI

### 1) Prerequisites

* Python **3.10+**

### 2) Install dependencies

**Using `uv` (recommended):**

```bash theme={null}
uv init
uv sync
```

Or with pip:

```bash theme={null}
pip install mcp-agent
pip install fastapi
```

### 3) Minimal code change: create an MCPApp()

`MCPApp` is the constructor for defining an MCP Application. The `mcp-agent` library looks for the `MCPApp` when configuring the application in the hosted cloud platform.

Make sure your server creates an MCPApp() and wires it to your FastMCP instance.

```python main.py theme={null}
from mcp_agent.app import MCPApp
from fastmcp import FastMCP  # import if your project uses FastMCP

mcp = FastMCP(
    name="your-app-name",
    message_path="/sse/messages",  # important: aligns with your SSE path
    stateless_http=True,           # recommended for cloud hosting
)

# ❗️ Key addition: register your MCP server as an mcp-agent App
app = MCPApp(
    name="your-app-name",
    description="your-app-description",
    mcp=mcp,
)

# ----- Your ChatGPT Application code here -----
```

These are the key changes needed for mcp-agent cloud hosting.

### 4) Add deployment config & secrets

Create two files at the repo root:

```yaml mcp_agent.config.yaml theme={null}
# Execution engine: asyncio or temporal
execution_engine: asyncio

name: "your-app-name"
description: "your-app-description"

logger:
  transports: [console, file]
  level: info
  path: logs/mcp-agent.log
```

```yaml mcp_agent.secrets.yaml theme={null}
# You can leave this blank. This is useful if you want to pass in keys or secrets to your MCP server
```

### 5) Deploy to mcp-agent cloud

With `uv`:

```bash theme={null}
uv run mcp-agent login
uv run mcp-agent deploy --no-auth
```

Or with `venv`:

```bash theme={null}
mcp-agent login
mcp-agent deploy --no-auth
```

<Info>Support for OAuth coming soon!</Info>

After a successful deploy, you'll see a cloud URL like:

```
https://<deployment-id>.deployments.mcp-agent.com/sse
```

### 6) Test in ChatGPT

1. Enable Developer Mode in ChatGPT.
2. Go to Settings → Connectors and add your app's MCP server.
3. Use your cloud URL, making sure it ends with `/sse`.

<Note>ChatGPT connects to the SSE endpoint, so the `/sse` suffix is required.</Note>

![Adding a custom connector to ChatGPT](https://andrew-dev-s3.s3.us-east-1.amazonaws.com/chatgpt.com_\(thumbnails\).png)

***

## Troubleshooting

* **404 / Connection errors in ChatGPT**: Ensure your URL ends with `/sse` and your code's `message_path` is `/sse/messages`.
* **Auth errors**: If you are unable to deploy because of an Auth issue, make sure you run `mcp-agent login`. If you are unable to access your ChatGPT app, make sure you deployed with the `--no-auth` configuration to make sure you can access your application.
* **MCP Inspector**: If you want to test without ChatGPT, you can use [MCP Inspector](https://modelcontextprotocol.io/docs/tools/inspector) (a debugging tool) for MCP servers to validate to make sure your MCP application is properly configured.

## Additional Resources

* [Example ChatGPT Apps](https://github.com/lastmile-ai/openai-apps-sdk)
* [mcp-agent repo](https://github.com/lastmile-ai/mcp-agent)