The start time

The start time in any allowable XSD representation of date, time or dateTime. This will normally be a clock time or date.
The start condition

This can describe the condition(s) that has to be met before an action can begin, such as in a recipe. Semantics are unexplored but could be used to control robotic operations.
The duration of the action

Semantics undefined.
The end time

The start time in any allowable XSD representation of date, time or dateTime. This will normally be a clock time or date.

The end condition

At present a human-readable string describing some condition when the ac tion should end. As XML develops it may be possible to add machine-processable semantics in this field.
Number of times the action should be repeated