Rasa2.0.0: Warning for nlu_fallback-Intent

While training a model with rasa2.0.0 I get the following warning:

UserWarning: Intent 'nlu_fallback' has only 1 training examples! Minimum is 2, training may fail.

Am I supposed to use the nlu_fallback intent? I doubt so, because it is used for low severity predictions…

Did you add the intent to your nlu.yml? You shouldn’t need to.


i have the same issue. I didn’t add Intent nlu_fallback to my nlu.yml

@tebot we’ve got an open issue for that here, we’ll work on fixing it!

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I noticed that the Fallback don’t really works by me.

When I type in some random letters like “sdfasdf” or “blablabla” it recognise them as names with a confidence around 0.91

Is this because of my configurations or because the nul_fallback has only 1 training examples?

(or are this common names anywhere in the world? :sweat_smile:)

my config.yml looks like this:

language: de_core_news_md

   - name: SpacyNLP
   - name: SpacyTokenizer
   - name: SpacyFeaturizer   
   - name: RegexFeaturizer 
   - name: LexicalSyntacticFeaturizer
   - name: CountVectorsFeaturizer
   - name: CountVectorsFeaturizer
     analyzer: char_wb
     min_ngram: 1
     max_ngram: 4
   - name: DIETClassifier
     epochs: 300
   - name: EntitySynonymMapper
   - name: ResponseSelector
     epochs: 100
   - name: FallbackClassifier
     threshold: 0.3
     ambiguity_threshold: 0.1

  - name: MemoizationPolicy
  - name: TEDPolicy
    max_history: 12
    epochs: 100
  - name: RulePolicy
    core_fallback_threshold: 0.3
    core_fallback_action_name: "action_default_fallback"

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Hello, I got the same issue but with more intents than mentioned before.

I think the first two “EXTERNAL_reminder” and “nlu_fallback” are clear. For the last two I had the idea to create intents, that are only triggered by using “/reconnect” or “/welcome”. My frontend generates an session id. The first time a user visits the page and the socket connection is established, a “/welcome” message is send. If the session id already exists, “/reconnect” is send to Rasa. So I don’t need any examples for this intents, they should only be triggered by using a “/”.