To add your own tool service to your workflow:
- Expand Service templates under Available services in the Service Panel.
- Select Tool
- Drag and drop the Tool to the Workflow Diagram.
- In a dialog that pops up, configure the Tool service.
- Start by typing the commands that you want to run into the Command tab.
Note that you can add a Tool service from the Insert menu as well.
The above has only added an "empty" Tool service to the workflow. You need to enter details of the actual Tool to be executed in order for this service to make any sense.