# File lib/new_relic/agent/synthetics_monitor.rb, line 19
      def on_before_call(request) #THREAD_LOCAL_ACCESS
        encoded_header = request[SYNTHETICS_HEADER_KEY]
        return unless encoded_header

        incoming_payload = deserialize_header(encoded_header, SYNTHETICS_HEADER_KEY)

        return unless incoming_payload &&
            is_valid_payload?(incoming_payload) &&
            is_supported_version?(incoming_payload) &&
            is_trusted?(incoming_payload)

        state = NewRelic::Agent::TransactionState.tl_get
        txn = state.current_transaction
        txn.raw_synthetics_header = encoded_header
        txn.synthetics_payload    = incoming_payload
      end