Create an account on Twilio (you'll need to verify a mobile number to proceed)
In order to create a SMS service you have to buy a Twilio phone number (any country is fine).
Twilio sends notification of incoming messages with a callback, use ngrok to expose your development instance of Node-RED to a public address, open a Terminal window and
ngrok http localhost:1880
You should get something like this
The address https://*.nkrok.io is the public URL that points back to your development machine.
First go to the Messaging services section and create a new service and pick up "Chatbot/Interactive 2-way" from the drop down menu.
Associate the Twilio number to this new service
Then check the "Process inbound message" and fill it using the ngrok address from the Terminal window, it should be something like
Now switch to RedBot and create a connection for the
Twilio Sender node: the Accound SID and Auth Token will be requested, you'll find both in the Twilio's Dashboard
Also don't forget to fill the Sender Name (the Twilio number you bought in the first step).
To verify that everything is working fine, try a simple flow to send out an SMS
In the Conversation node set the chatId with the recipient's phone number (complete with the international prefix). Be sure that the international prefix of recipient phone number is included in the Geographic Permissions.