Confispex.get

You're seeing just the function get, go back to Confispex module for more information.
Link to this function

get(variable_name, server \\ Confispex.Server)

Specs

Get a value from store by specified variable name (key) and cast it according to schema.

Example

config :my_app, MyApp.Repo, url: Confispex.get("DATABASE_URL")

In case of any error during casting nil is returned, errors are saved and can be retrieved later using report/1 function.