A label has a name and a value and is a way of displaying information in ecflowviewecflow_ui. Since the value can be anything (ASCII) it cannot be used in triggers.
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foo is the "name" of the label and the empty string is the default value of the label (the value is shown when the suite begins). After the command begins it looks like:
In an ecFlow job file, you can then modify your task to change the label while the job is running, e.g.
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