Trying to set a custom variable for inbound call in Twilio Studio and pass to Zapier. Zapier does not see custom variables, only one I see could possibly use is "Annotation" however cant find what that is or how to set.
See the reference here, https://www.twilio.com/docs/voice/api/call, but doesn't help with what Annotation variable is or used for.
$call = $twilio->calls
->create("+15558675310", // to
"+15017122661", // from
array("url" => "http://demo.twilio.com/docs/voice.xml")
);
print($call->sid);
OUTPUT
{
"account_sid": "AC3b3775dff0b80a1bc37850e08102db58",
"annotation": null,
"answered_by": null,
Annotation = "12345" or whatever user inputs