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Rasa NLU Examples

This repository contains some example components meant for educational and inspirational purposes. These are components that we open source to encourage experimentation but these are components that are not officially supported. There will be some tests and some documentation but this is a community project, not something that is part of core Rasa.


The goal of these tools will be to be compatible with the most recent version of rasa only. You may need to point to an older release of the project if you want it to be compatible with an older version of Rasa.

The following components are implemented.



rasa_nlu_examples.meta.Printer docs

This component will print what each featurizer adds to the NLU message. Very useful for debugging. You can find a tutorial on it here.


StanzaTokenizer docs

We support a tokenizier based on Stanza. This tokenizer offers part of speech tagging as well as lemmatization for many languages that spaCy currently does not support. These features might help your ML pipelines in those situations.

ThaiTokenizer docs

We support a Thai tokenizier based on PyThaiNLP link.

Dense Featurizers


rasa_nlu_examples.featurizers.dense.FastTextFeaturizer docs

These are the pretrained embeddings from FastText, see for more info here. These are available in 157 languages, see here.


rasa_nlu_examples.featurizers.dense.BytePairFeaturizer docs

These BytePair embeddings are specialized subword embeddings that are built to be lightweight. See this link for more information. These are available in 227 languages and you can specify the subword vocabulary size as well as the dimensionality.


rasa_nlu_examples.featurizers.dense.GensimFeaturizer docs

A benefit of the gensim library is that it is very easy to train your own word embeddings. It's typically only about 5 lines of code. That means that you could train your own word-embeddings and then easily use them in a Rasa pipeline. This can be useful if you have reason to believe that standard training corpora (like Wikipedia) are not valid for your use-case.


You can find the contribution guide here.