Entities are Dialogflow's mechanism for identifying and extracting useful data from natural language inputs.
While intents allow your agent to understand the motivation behind a particular user input, entities are used to pick out specific pieces of information that your users mention — anything from street addresses to product names or amounts with units. Any important data you want to get from a user's request will have a corresponding entity.
Dialogflow is equipped with numerous system entities, which allow agents to extract information about a wide range of concepts without any additional configuration. For example, system entities are available for extracting dates, times, and locations from natural language inputs.
If you need to extract information about concepts beyond those covered by Dialogflow's system entities, you can define your own developer entity types. For example, a brand might create an entity type to recognize its unique set of product names.
It is also possible to define entity types that apply only to a specific conversation. For example, you might create an entity type to represent the time-sensitive options available to a particular user when making a booking. These are called session entity types.
The documents in this section describe the various categories of entities and how you can use them.