Twilio Sms

Webhook for inbound SMS received through Twilio.

Body MUST have a default. Twilio sends Body= (empty) for a media-only MMS — a patient texting a photo of their insurance card with no caption — and FastAPI treats an empty form value as absent, so a required Body fails validation with a 422 and the message is never recorded. Twilio does not retry inbound webhooks on 4xx, so those messages were lost outright (VM-10490). The legacy Flask route read request.values["Body"], which returned the empty string, hence the regression on migration.

To/From/MessageSid stay required: Twilio always sends them, so a request without them is malformed rather than media-only.