Rule that triggers custom action when a slot is filled with an arbitrary value

I want a rule that triggers a custom action when a certain slot is filled with an arbitrary value. Something like this doesn’t trigger the rule

- rule: Trigger custom action
  condition:
  - slot_was_set:
    - some_text_slot
 steps:
  - intent: intent
  - action: custom_action

@yem Hope it will help.

 - rule: Trigger custom action
      condition:
      - slot_was_set:
       - requested_slot: cuisine
     steps:
      - intent: greet
      - action: custom_action

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