Azure Function Add Assembly

 #r "Newtonsoft.Json"
 #r "Microsoft.WindowsAzure.Storage"

The following assemblies are automatically added by the Azure Functions hosting environment:

mscorlib
System
System.Core
System.Xml
System.Net.Http
Microsoft.Azure.WebJobs
Microsoft.Azure.WebJobs.Host
Microsoft.Azure.WebJobs.Extensions
System.Web.Http
System.Net.Http.Formatting

The following assemblies may be referenced by simple-name (for example, #r “AssemblyName”):

Newtonsoft.Json
Microsoft.WindowsAzure.Storage
Microsoft.ServiceBus
Microsoft.AspNet.WebHooks.Receivers
Microsoft.AspNet.WebHooks.Common
Microsoft.Azure.NotificationHubs

Sources:

https://docs.microsoft.com/en-us/answers/questions/107470/how-to-add-reference-to-directives-in-azure-functi.html