What is a feature?
A feature makes an intent more specific. It is a sub-context in the intent context. Technically it is a semantic representation that allows to augment that of the intent that has been extracted. Keep in mind that features are always part of one specific intent.
Example: the intent customer+service may have a feature called terrible.
Are features always unigrams?
Features don’t have to necessarily be unigrams, as the semantic context that augments the intent may be better represented by many words.
In the previous example terrible is the best representation that uses just one word.
In an another example where we have the intent need+help, a feature send+email shows that the best representation is a bigram.
I’m not getting any feature inside an intent, what may be happening?
It may be possible that there is no way to sub-classify texts from that intent. This can happen in intents that are focused on one specific semantic context without many variations.