Here is a color palette based on your request for a 12 hue pastel palette with high contrast:

json
{
  "palette_name": "High Contrast Pastel",
  "colors": [
    {
      "name": "Pastel Pink",
      "hex_code": "
          
          #FFB3BA
       "
    },
    {
      "name": "Pastel Blue",
      "hex_code": "
          
          #A2C2E9
       "
    },
    {
      "name": "Pastel Green",
      "hex_code": "
          
          #B9FBC0
       "
    },
    {
      "name": "Pastel Yellow",
      "hex_code": "
          
          #FFF6E5
       "
    },
    {
      "name": "Pastel Purple",
      "hex_code": "
          
          #D6C9E7
       "
    },
    {
      "name": "Pastel Orange",
      "hex_code": "
          
          #FFABAB
       "
    },
    {
      "name": "Pastel Teal",
      "hex_code": "
          
          #A1D9D3
       "
    },
    {
      "name": "Pastel Lavender",
      "hex_code": "
          
          #E5C8E5
       "
    },
    {
      "name": "Pastel Peach",
      "hex_code": "
          
          #FFD8C2
       "
    },
    {
      "name": "Pastel Mint",
      "hex_code": "
          
          #C2F9C2
       "
    },
    {
      "name": "Pastel Coral",
      "hex_code": "
          
          #FF6B6B
       "
    },
    {
      "name": "Pastel Gold",
      "hex_code": "
          
          #F9E89D
       "
    }
  ]
}

This palette features soft pastel shades that provide a gentle yet high-contrast visual experience, making them versatile for various design applications.

Would you like any adjustments to this palette, or do you have other color themes in mind?