# Custom AI app

> Add Holistics MCP to a custom AI application built with the OpenAI Responses API to query data and run analytics.

If you're building an AI application with the OpenAI API, you can add Holistics as an MCP tool so your app can query data and run analytics as part of its workflow.

Include the Holistics MCP server in your tool list when calling the OpenAI Responses API:

```typescript

const client = new OpenAI({
  apiKey: "<YOUR_OPENAI_KEY>",
});

async function chat(input: ResponseInput) {
  const completion = await client.responses.create({
    model: "gpt-4.1",
    input: input,
    tools: [
      {
        type: "web_search",
      },
      {
        type: "mcp",
        server_label: "holistics_mcp",
        server_url: "<MCP_SERVER_ADDRESS>",
        server_description: "Holistics MCP to access my BI and business data",
        headers: {
          "X-Holistics-Key": "<YOUR_HOLISTICS_API_KEY>",
        },
        require_approval: "never",
      },
    ],
    tool_choice: "auto",
    parallel_tool_calls: true,
  });

  console.log(completion.output_text);
}
```

Replace `<MCP_SERVER_ADDRESS>` with your [connection URL](/docs/ai/mcp-server/setup#oauth) and `<YOUR_HOLISTICS_API_KEY>` with your API key.