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

# Configuration

> Configure the Semust MCP Server

## Environment Variables

| Variable          | Required | Default                         | Description         |
| ----------------- | -------- | ------------------------------- | ------------------- |
| `SEMUST_API_KEY`  | Yes      | —                               | Your Semust API key |
| `SEMUST_BASE_URL` | No       | `https://api.semust.com/v1/mcp` | API base URL        |

## Getting Your API Key

<Steps>
  <Step title="Sign In">
    Go to [app.semust.com](https://app.semust.com) and sign in to your account.
  </Step>

  <Step title="Navigate to Settings">
    Go to [Settings > API Key](https://app.semust.com/settings) in your Semust account.
  </Step>

  <Step title="Copy Your Key">
    Copy the API key. You'll use this in your `.env` file or client configuration.
  </Step>
</Steps>

## Configuration Methods

You can provide the API key in two ways:

### Option 1: `.env` File

Create a `.env` file in the MCP server directory:

```bash .env theme={null}
SEMUST_API_KEY=your_api_key_here
SEMUST_BASE_URL=https://api.semust.com/v1/mcp
```

### Option 2: Client Configuration

Pass the API key directly in your AI client's MCP configuration (see [Setup Guides](/mcp/setup/claude-desktop)):

```json theme={null}
{
  "env": {
    "SEMUST_API_KEY": "your_api_key_here"
  }
}
```

<Tip>
  When both `.env` and client config provide the key, the client config takes precedence.
</Tip>

## Security Requirements

The server enforces HTTPS for all API communication:

* `SEMUST_BASE_URL` must use `https://`
* The only exception is `localhost` / `127.0.0.1` for local development
* Plaintext HTTP to remote hosts is rejected at startup

<Warning>
  Never share your API key or include it in client-side code. Keep it in environment variables or secure configuration files.
</Warning>