The Set Dictionary Value action (v8+) takes dictionary name and a key name and allows you to set the specified plain text value, by either typing in the text field, or selecting a Token.
The Dictionary name, Key name, and value can all contain text tokens, allowing a wide variety of uses. You can turn off token processing for the value field to make it easier to include backslash or percent characters.
Setting the value to the empty string deletes the key and value from the dictionary. Setting all the values to the empty string deletes the dictionary.