From docs
The
Dgraph.Authorizationobject uses the following syntax:{"Header":"", "Namespace":"", "Algo":"", >"VerificationKey":"", "JWKURL":"", "Audience":[], >"ClosedByDefault": false}This object contains the following values:
Headeris the header that requests use to store the signed JWT.
So whatever the string you put in that value in the schema is the name of the header it looks for.