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

# Testing

> Testing your MCP server

## Unit testing

When initializing your MCP server, the CLI will also scaffold the necessary files to perform unit testing with Vitest.

The tests are located in the `test` directory and should be named using the pattern `[name].test.ts`.

To run the tests, you can use the following command:

```bash theme={null}
npm run test
```

Or, if you prefer using the @vitest/ui interface like we do:

```bash theme={null}
npm run test:ui
```

## Using a MCP host

When running the dev command, the Vite plugin will create a `.cursor/mcp.json` file in the root of your project. This file will connect Cursor to your MCP server using the `@mcplug/client` package.

You can also use this same JSON file to connect your MCP server to other AI clients like Claude.

<Info>
  If you have configured constants in your tools, you will need to set them in the `mcp.json` file inside the `env`
  property.

  For example, if your tool has a constant called `_API_KEY`, you would set it in the `env` property like this:

  ```json theme={null}
  {
    "env": {
      "API_KEY": "your_api_key"
    }
  }
  ```
</Info>