"The Google Documents List data API allows client applications to upload documents to Google Documents and list them in the form of Google data API ("GData") feeds. Your client application can request a list of a user's documents, and query the content in an existing document.
Here are some of the things you can do with the Documents List data API:
- Upload the word processing documents and spreadsheets on your computer to allow you to back them up or collaborate online when editing.
- Find all of your documents that contain specific keywords.
- Get a list of spreadsheets which can be accessed through the Google Spreadsheets data API.
The contents of Google Documents List Data API includes:
- Single-user "installed" client authentication
- Multiple-user web application client authentication
- Upgrading to a session token
For more read the guide protocol.