Coveo for Sitecore 5 is now available!

Adding Custom Parameters Using the Coveo for Sitecore Legacy Search UI Framework

Coveo for Sitecore 4.1 (November 2018)

Coveo already provides a list of parameters for the Search, Facet, and Sort components. However, if you need to specify your own parameters, you can easily do so. The following sections describe how to add custom parameters by using the Additional Parameters field or by creating a new parameters template.