Rule that checks if slot was set for any value

Im trying to write a rule that checks if a slot was set regardless of the value of the slot. All the examples I see look like this:

- rule: Only say `hello` if the user provided a name
  condition:
  - slot_was_set:
    - user_provided_name: true

But my slot is a text field with many possible values and I dont care about the value, I just want to trigger the rule if the slot was set to any value. How do I write that kind of rule?

Could I write the rule like this?:

- rule: Only say `hello` if the user provided a name
  condition:
  - slot_was_set:
    - some_text_slot

Also is there some developer documentation/reference showing all the possible rules and condition parameters since the docs only give examples but not the full reference?

you can put in the rules whatever you can put in the stories, it essentially the same format

- slot_was_set:
    - some_text_slot

if it works in the stories, it’ll work exactly the same way in the rules