Environment variables set for MCP are truncated to 100 characters in Cursor version 0.48

Bug Reports
1

In Windows and Cursor version 0.48, I attempted to retrieve data from MySQL using the MySQL MCP server (GitHub - designcomputer/mysql_mcp_server: A Model Context Protocol (MCP) server that enables secure interaction with MySQL databases) through chat inside Cursor. To do this, I configured mcp.json like this:

{
  "mcpServers": {
    "mysql": {
      "command": "uv",
      "args": [
        "--directory",
        "C:\\Work\\mysql_mcp_server\\src\\mysql_mcp_server",
        "run",
        "mysql_mcp_server"
      ],
      "env": {
        "MYSQL_HOST": "jdbc:mysql://thishost-is-just-an-example.com:3306/anyway?format=true&is=true&like=false&that=Asia/Tokyo",
        "MYSQL_PORT": "3306",
        "MYSQL_USER": "username",
        "MYSQL_PASSWORD": "password",
        "MYSQL_DATABASE": "localhost"
      }
    }
  }
}

Then, in a chat set to agent mode, I typed “Get the data from table 〇〇”, which successfully triggered the MCP tool and executed the query:

{ "query": "SELECT * FROM 〇〇;" }

However, the result returned was:

Error executing query: 2005 (HY000): Unknown MySQL server host ‘jdbc:mysql://thishost-is-just-an-example.com:3306/anyway?format=true&is=true&like=false&that=Asia/T’ (11001)

The host name in the error message appears to be the first 100 characters of the host string I set in mcp.json, with the remaining characters seemingly ignored.

At this point, I’m not sure whether the issue lies with the MCP server or with Cursor itself. Has anyone else experienced a similar issue? (I couldn’t find any related reports in my search.)
Apologies in advance if this turns out not to be a bug on Cursor’s side.