Under the terms of the agreement, they will allow Ukraine to conduct maritime trade out of the Black Sea. It is my understanding that Ukraine typically exports over 30m metric tons of grain via the Black Sea, among other products.
Similarly, Russia will also be permitted to export agricultural products via the Black Sea.
What were you hoping, that a deal would be struck whereby Ukraine can export their products but Russia would still be barred? I cannot see why you would expect Russia to accept that.