Carrier inbound-SMS callback
SMS Webhooks
Carrier inbound-SMS callback
Unauthenticated carrier callback for inbound SMS on the 844/833 lines. Verifies a Flowroute HMAC (or voip.ms shared-secret) against the raw body BEFORE parsing; invalid/missing signature returns 401. Handles STOP/HELP/START keywords and records the inbound message.
POST
Carrier inbound-SMS callback
Body
application/json
Inbound SMS payload from a carrier callback (Flowroute or voip.ms).
Carrier payloads differ; this schema captures the common fields. Flowroute
posts JSON with to/from/body; voip.ms posts did/from/
message (mapped by the endpoint). Unknown extra keys are ignored.