Calling Global Custom Action Using Java Script

Hi,

I have created a HTML page which is having a Button, which calls a custom action with input parameters & that custom action again fire's a plugin & returns some value which we have to parse & update in HTML.

I tried with - https://deepakexploring.wordpress.com/2013/10/23/actions-in-crm-2013/ this approach & it is working fine but in this approach i have to pass EntityId & EntityName.

Please suggest some approach where we do not have to use Entity related details.

Regards,

Anand