fun trackingId(trackingId: String): RoutingOptions.Builder

Specifies an identifier for the request. The value should be unique for each request. The value must match the regular expression '^a-zA-Z0-9-{1,100}$'. If specified, the same value is sent back in the similar-named response header. Otherwise, a generated value may be sent back.

Important: This is a Public Preview API. It may be changed or removed at any time.