Here’s the updated color palette with a Rusty Gold color added. The hex code for rusty gold is typically #B86A3E . Here’s the revised palette:

{
  "palette_name": "Sweet and Vibrant",
  "colors": [
    {
      "name": "Vanilla Cream",
      "hex_code": "
          
          #F8E8D6
       "
    },
    {
      "name": "Buttered Biscuit",
      "hex_code": "
          
          #E4C5A6
       "
    },
    {
      "name": "Spiced Cocoa",
      "hex_code": "
          
          #C08A7E
       "
    },
    {
      "name": "Mocha Drizzle",
      "hex_code": "
          
          #8E6253
       "
    },
    {
      "name": "Pistachio Whip",
      "hex_code": "
          
          #A5C49D
       "
    },
    {
      "name": "Berry Coulis",
      "hex_code": "
          
          #DA5C7A
       "
    },
    {
      "name": "Vibrant Teal",
      "hex_code": "
          
          #008080
       "
    },
    {
      "name": "Honeycomb Bliss",
      "hex_code": "
          
          #F4D988
       "
    },
    {
      "name": "Rusty Gold",
      "hex_code": "
          
          #B86A3E
       "
    }
  ]
}

This palette now includes a warm, rustic gold hue that complements the existing colors beautifully. If you have any further adjustments or requests, feel free to let me know!