Warning: This document is for an old version of Rasa Core. The latest version is 0.14.5.

Domain Format

The Domain defines the universe in which your bot operates. It specifies the intents, entities, slots, and actions your bot should know about. Optionally, it can also include templates for the things your bot can say.

As an example, the DefaultDomain has the following yaml definition:

# all hashtags are comments :)
 - greet
 - default
 - goodbye
 - affirm
 - thank_you
 - change_bank_details
 - simple
 - hello
 - why
 - next_intent

 - name

    type: text

    - "hey there {name}!"    # variable will be filled by slot with the same name or by custom code
    - "goodbye 😢"
    - "bye bye 😢"              # multiple templates will allow the bot to randomly pick from them
    - "default message"

  - utter_default
  - utter_greet
  - utter_goodbye

What does this mean?

Your NLU model will define the intents and entities that you need to include in the domain.

slots are the things you want to keep track of during a conversation, see Using Slots .

actions are the things your bot can actually do. For example, an action can:

  • respond to a user
  • make an external API call
  • query a database

see Custom Actions

For a more complete example domain, check the Quickstart.

Custom Actions and Slots

To reference custom actions and slots in your domain, you need to reference them by their module path. For example, if you have a module called my_actions containing a class MyAwesomeAction, and module my_slots containing MyAwesomeSlot, you would add these lines to the domain file:

  - my_actions.MyAwesomeAction

  - my_slots.MyAwesomeSlot

Utterance templates

Utterance templates are messages the bot will send back to the user. Either automatically by an action with the same name as the utterance (e.g. in the above example the utter_default template and action) or by an action with custom code.

Images and Buttons

Templates defined in a domains yaml file can contain images and buttons as well:

  - text: "Hey! How are you?"
    - title: "great"
      payload: "great"
    - title: "super sad"
      payload: "super sad"
  - text: "Here is something to cheer you up:"
    image: "https://cdn77.eatliver.com/wp-content/uploads/2017/10/trump-frog.jpg"


Please keep in mind that it is up to the implementation of the output channel on how to display the defined buttons. E.g. the cmdline interface can not display buttons or images, but tries to mimic them in the command line.


You can also use variables in your templates to insert information collected during the dialogue. You can either do that in your custom python code or by using the automatic slot filling mechanism. E.g if you got a template like this:

  - text: "Hey, {name}. How are you?"

Rasa will automatically fill that variable with a value found in a slot called name.

In custom code, you can retrieve a template by using:

class ActionCustom(Action):
   def name(self):
      return "action_custom"

   def run(self, dispatcher, tracker, domain):
      # send utter default template to user
      dispatcher.utter_template("utter_default", tracker)
      # ... other code
      return []

If the template contains variables denoted with {my_variable} you can supply values for the fields by passing them as key word arguments to utter_template:

dispatcher.utter_template("utter_default", tracker, my_variable="my text")


If you want to randomly vary the response sent to the user, you can list multiple responses and Rasa will randomly pick one of them, e.g.:

  - text: "Hey, {name}. How are you?"
  - text: "Hey, {name}. How is your day going?"

Ignoring entities for certain intents

If you want entities to be ignored for certain intents, you can add the use_entities: false parameter to the intent in your domain file like this:

  - greet: {use_entities: false}

This means that entities for those intents will be unfeaturized and therefore will not impact the next action predictions. This is useful when you have an intent where you don’t care about the entities being picked up. If you list your intents as normal without this parameter, the entities will be featurized as normal.


If you really want these entities not to influence action prediction we suggest you make the slots with the same name of type unfeaturized