Which video conferencing api could help us with this?

We are looking for a video conferencing/desktop sharing tool which api would allow us to generate a link which we could send to the person who we would like to connect to our desktop and view our screen. What video conferencing/desktop sharing tool would you suggest for us in this situation? Besides being able to show my desktop to the person I have sent out the link to, I would also like to be able to have two way audio. It is important to note that we are not talking about a stand alone tool like GoToMeeting or Google Hangouts, but would like to create a web app that would generate this link via the video conferencing tools api which we then could send out via our own web app.