Formerly known as the “AutoCAD I/O API”, the Design Automation API provides the ability to run scripts on your design files, leveraging the scale of the Forge Platform to automate repetitive tasks.
At present, the API provides the ability to run scripts on AutoCAD DWG files, with plans in the works to expand to file types generated by other design software.
Autodesk services are governed by the following Terms of service http://www.autodesk.com/company/legal-notices-trademarks/terms-of-service-autodesk360-web-services/autodesk-web-services-api-beta-terms-of-service
The status of the Autodesk services can be found here https://developer.autodesk.com/en/support/api-status
Authentication is done with a 2-legged token a guide on how to create an application and retrieves the bearer token is available in the Forge Documentation
There is a wealth of tools and libraries available for the forge services on their Github