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The parameter_meta component is an optional property of a task. It is intended to store descriptions of input arguments and parameters used in the task command, which is particularly helpful if your variable names are not descriptive enough. Any item (i.e. input_file) in this section MUST be present in the command line.
Usage example
parameter_meta {
input_file: "the BAM file to process"
sample_id: "the name of a sample"
}