While you can use Dialogflow by making direct REST over HTTP requests, we provide client libraries for several popular languages.
Google Cloud Client Libraries
Dialogflow client libraries are built on Google Cloud Client Libraries. This common infrastructure provides functionality for API-specific library implementations, but it also provides types and methods that you may use directly when using any Cloud API.
The Dialogflow quickstart guides provide basic information on authentication. For more detailed information, see Getting Started with Authentication in the GCP authentication guide.
Dialogflow provides client libraries and guides for the following languages: