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

# Cursor

> Add the Arcus MCP server to Cursor

Connect [Cursor](https://cursor.com) to the Arcus docs MCP server so its agent and chat panes can answer questions and write code grounded in the live spec.

## Prerequisites

* Cursor 0.45 or newer (MCP support required)

## Setup

<Steps>
  <Step title="Open MCP settings">
    In Cursor, open **Settings → Cursor Settings → MCP** (or run the command palette: *MCP: Add new server*).
  </Step>

  <Step title="Add the Arcus server">
    Add an entry with the following configuration:

    ```json theme={null}
    {
      "mcpServers": {
        "arcus-docs": {
          "url": "https://docs.arcus.xyz/mcp"
        }
      }
    }
    ```

    Save the file. Cursor stores user-level MCP servers in `~/.cursor/mcp.json` and project-level ones in `.cursor/mcp.json` at the repo root — pick whichever scope fits.
  </Step>

  <Step title="Authenticate">
    Cursor will prompt you to authenticate the first time it talks to the server. Click **Sign in**, complete the OAuth flow in your browser, and return to Cursor.
  </Step>

  <Step title="Try it">
    Open the agent or chat pane and ask:

    > *Show me how to subscribe to the orderbook WebSocket channel for `BTC-USD`.*

    Cursor will call the MCP server and ground its answer in the live Arcus reference.
  </Step>
</Steps>

## Notes

* If the OAuth popup never appears, upgrade Cursor — remote MCP with OAuth landed in recent versions.
* For the underlying server details, see the [MCP server overview](/ai-tools/mcp).