Is there any SDK for integrating Jira Service Desk with an external website?

[Maheswari]

We want to show the jira service desk agent page inside an iframe in our application. The user is already logged into our application. So we don't want to show the jira login again to access the jira page.  

We don't have any SSO in our organization. So don't want to do it via SSO since it need some change in our existing website.

Is there any other methods to integrate such as any ticket (cookie) authentication(by appending a ticket to the url). Or Is there any SDK that provides an authorised ticket to access the jira?