Workflow is executed as an asynchronous process so messages cannot be directly displayed in the Reltio UI. You can add a comment to a workflow with the API:
PUT: https://prod-workflow.reltio.com/workflow-adapter/workflow/{{tenantID}}/tasks/{{workflowTaskID}}
{ "processInstanceComment": "my new comment" }
Alternatively, you could get the task assignee or createdBy user and send a message directly to them from API
GET: https://sales-workflow.reltio.com/workflow-adapter/workflow/{{tenantID}}/tasks/{{workflowTaskID}}
If you are launching the workflow from a synchronous beforeSave LCA then a message thrown should be displayed in the Reltio UI.
RDM workflow is currently not customizable so you cannot throw any messages. RDM will publish events to a queue which you could subscribe to, in order to perform some asynchronous activity. That is documented here:
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Dan Gage
Principal Solution Consultant
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