How to describe “object” arguments in jsdoc?

// My function does X and Y.
// @params {object} parameters An object containing the parameters
// @params {function} callback The callback function
function(parameters, callback) {
}

But how do I describe how the parameters object should be structured? For example it should be something like:

{
  setting1 : 123, // (required, integer)
  setting2 : 'asdf' // (optional, string)
}