Dear all, I was thinking about how to improve some of my tools and wondered if there is any way to have dynamic default values for parameters (depending on other parameters). Obviously this won't make sense in all cases, but as a specific example, consider my Venn Diagram tool: https://bitbucket.org/peterjc/galaxy-central/src/9f66c5d1fca8/tools/plotting... I have separate parameters for each dataset (file input) and its caption (text input). Like so: <param name="set" type="data" format="tabular,fasta,fastq,sff" label="Members of set" help="Tabular file (uses column one), FASTA, FASTQ or SFF file."/> <param name="lab" size="30" type="text" value="Group" label="Caption for set"/> Is something like this possible (or generally useful?) <param name="set" type="data" format="tabular,fasta,fastq,sff" label="Members of set" help="Tabular file (uses column one), FASTA, FASTQ or SFF file."/> <param name="lab" size="30" type="text" value="$set.name" label="Caption for set"/> i.e. The default value of the label text parameter "lab" would be the human friendly name of the associated data file parameter "set". I'd expect changing the file to also change the text box. I have thought of a workaround, but not yet tried it: Use the empty string as the default, and use an if statement in the Cheetah template for constructing the command line string. Thanks, Peter