Read this first: New zero code install Universal Co-browsing which allows you to Co-browse without any installation or integration required.
Installation and first session
How to install Upscope
Troubleshooting installation e.g. when not seeing CSS on your test environment
Integrating Upscope with your live chat system
Starting a session
Highlighting, spotlighting, making a call
Creating and managing teams
Understanding key features
The request agent button
Personal co-browsing link and proxy
How to use the console
Seeing Screenshots within Intercom, Zendesk, LiveChat
Typically, REST API is for enterprise plans or for white labelling and needs to be requested in advance as part of a special plan.