The following are general areas where the API is suitable:
Creating add-ins and macros to automate repetitive tasks in the Autodesk Revit user interface
Enforcing project design standards by checking for errors automatically
Extracting project data for analysis and to generate reports
Importing external data to create new elements or parameter values
Integrating other applications, including analysis applications, into Autodesk Revit products
Creating Autodesk Revit project documentation automatically