Hey @Mizuha  Eden from the support engineer team here.

Each Canvas Kit request is signed by Intercom via an X-Body-Signature header. We do this so that you can check that each request is actually sent by Intercom by decoding the signature.

The value is computed by creating a signature using the body of the JSON request and your app's OAuth client_secret value, which you can find on the Basic Info page of your app. You can read more about this in our documentation here.