The Gtdagenda API is implemented as a PHP page that accepts GET or POST requests and returns JSON or XML.
API clients must hit the URL http://app.gtdagenda.com/api2.php
All API requests must have a key argument indicating the user, except cmd=login.
|subject (type: string, required: Yes, Subject, choose from: task, project, goal, context, checklist)|
subjectid (type: string, required: Yes, Subject Id)
|id (type: integer, required: Yes, Subscription Id)|