Now, as for the Presentation details - that is available via the REST API -- take a look at https://<your-vco-host>:8281/api/docs -- right from that page, you will see that one of the REST API services is "PRESENTATION SERVICE" - click through there to see details on the Presentation for workflows.
When I browse the REST API for Presentation one of my test workflows, here is what I get back:
<?xml version="1.0" encoding="UTF-8" standalone="yes"?><presentation xmlns="http://www.vmware.com/vco" name="Inspect vCloud vApp" id="8F80808080808080808080808080808034808080012978762916636f5d959cf40" href="https://vco51.vcoteam.lab:8281/api/workflows/8F80808080808080808080808080808034808080012978762916636f5d959cf40/presentation/"> <relations> <link rel="up" href="https://vco51.vcoteam.lab:8281/api/workflows/8F80808080808080808080808080808034808080012978762916636f5d959cf40/"/> <link rel="instances" href="https://vco51.vcoteam.lab:8281/api/workflows/8F80808080808080808080808080808034808080012978762916636f5d959cf40/presentation/instances/"/> <link rel="add" href="https://vco51.vcoteam.lab:8281/api/workflows/8F80808080808080808080808080808034808080012978762916636f5d959cf40/presentation/instances/"/> </relations> <steps> <step hidden="false"> <messages/> <group hidden="false"> <messages/> <fields> <field type="vCloud:VApp" hidden="false" id="vApp"> <display-name>vApp</display-name> <description>vApp</description> <messages/> <constraints/> <decorators> <chooser type="list"> <sdk-object display-value="vCloud Director" href="https://vco51.vcoteam.lab:8281/api/catalog/vCloud/"/> </chooser> </decorators> <fields/> </field> <field type="boolean" hidden="false" id="nested"> <display-name>Use Nested VM Tests?</display-name> <description>Use Nested VM Tests?</description> <messages/> <constraints/> <decorators/> <fields/> <boolean>true</boolean> </field> </fields> </group> </step> </steps> <input-parameters> <parameter name="vApp" type="vCloud:VApp" description="vApp"/> <parameter name="nested" type="boolean" description="Use Nested VM Tests?"/> </input-parameters> <output-parameters> <parameter name="nested" type="boolean"/> <parameter name="vApp" type="vCloud:VApp"/> </output-parameters></presentation>
Hopefully that pasted code comes out ok... We can see in there the "decorators" tags that provide default value and Select as for the two inputs of my workflow.