Smartcar Webhooks

When to Use This Skill

• How do I receive Smartcar webhooks?
• How do I verify the Smartcar SC-Signature header?
• How do I respond to the Smartcar VERIFY challenge so my webhook activates?
• How do I handle VEHICLE_STATE and VEHICLE_ERROR events?
• Why is my Smartcar webhook signature verification failing?

Verification (core)

Smartcar signs every webhook with a hex-encoded HMAC-SHA256 of the raw request body, keyed with your Application Management Token (AMT, from the Smartcar Dashboard), in the SC-Signature header. On setup Smartcar also POSTs a one-time VERIFY event whose data.challenge you must hash with the same AMT and echo back within 15 seconds — otherwise the webhook never activates. This is Smartcar's own scheme, not the Standard Webhooks spec.