Workflow Object Inbound Configuration
It is possible to set an external identifier directly on a workflow object in place of using an External Trigger object connected to your object.
This not only adds convenience and flexibility, but also provides a way to tweak the behaviour of Alfred's input field for input objects.
The "Inbound Configuration..." is available from the contextual popup menu for the selected object in Alfred's workflow editor.
Objects with an External Identifier set have a small turquoise hint on the input of the object in Alfred's Workflow Editor.
For Input objects, the Inbound Mode option is enabled, and can be set to either Direct or Keyword. This mode affects both input via AppleScript or the External Trigger, and also workflow connected inputs.
This is the default behaviour, and how Alfred operated before 4.1. You'll see the input's icon to the right hand side of Alfred's window, and the input box is directly related to your specific input.
This mode essentially operates the same as if you had manually typed the keyword, selected the result to make it unique, then typed the argument. Alfred's window is in a context where you would be able to delete back past the keyword and return to Alfred's default results.
One advantage of keyword mode is that it will be remembered in Alfred's short term history.