Custom Action limitation with application/x-www-form-urlencoded payloads (Twilio WhatsApp case)

Hi,

I’m trying to call the Twilio Messages API (WhatsApp) from a Custom Action.

Twilio requires application/x-www-form-urlencoded POST bodies (To, From, Body in the request body).

However, in Custom Actions, even when the content type is set to application/x-www-form-urlencoded, the payload appears to be sent as JSON or query parameters, not as a true form-encoded body.

This results in Twilio errors like:
21604 – A 'To' phone number is required

The exact same request works via curl and Python (requests.post(data=...)) but fails from AJO.

• Is it a known limitation that Custom Actions don’t support true x-www-form-urlencoded bodies?
• Are there plans to support non-JSON request bodies?

Thanks!