You can retrieve the text you've copied into Telltail from this. It gives back you the result in plain text.
POST /set
You can store a text into Telltail with this. The request body needs to be JSON, and should have the form:
{"text":"text to store","device":"unknown"}
If you are making this request from a device which has Sync installed in it, then pass the same device name here what you passed to while installing Sync. Otherwise, leave it as unknown.