Applies to: SharePoint 2016 | SharePoint Foundation 2013 | SharePoint Online | SharePoint Server 2013
Each element manifest that defines a workflow must adhere to the Workflow Definition schema. A workflow definition is an XML file that contains the information that SharePoint Foundation requires to instantiate and run the workflow, such as the following:
The name, GUID, and description of the workflow
The URLs of any custom forms used in this workflow
The names of the workflow assembly, and the class within that assembly to call
Optionally, any custom metadata the workflow requires to run
The structure of the workflow definition schema is as follows.