TaskContract [VF AgSDK]

This is a class attribute to mark the task processor of a task.
DisplayName
This mandatory property is used in the Workflow Designer's drop-down list of all tasks to identify a specific task.
Examples:

Send Email
Add Deletion Lock
Transcode with TranscoderS4M

Description
A mandatory property that provides a (short) description of the task's purpose. Shown when the task has been selected in the Workflow Designer's drop-down list.
Guid
The GUID of the task. It is used to uniquely identify the specific task independent of its version.

Uniqueness of the task's Guid

The task's GUID must be uniquely generated when the first version of a task is created and must not change over time or for different versions of the same task.
If you do change the GUID of a task even without changing any other part of the task contract or your implementation, VidiFlow will not be able to execute workflows using the task with the old GUID.

Version
This specifies the mandatory version of the task as a string in the format "<major>.<minor>". It must match the version in the class' namespace (besides the separator).
Categories
This is an optional list of strings that allows to define different (filter) contexts for the task in the Workflow Designer. Typical examples are

Use cases in which the task is used, e.g. "Transcoding"
3^rd party vendors or products that the task connects to, e.g. "Vantage"
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