The Trade page lets a player propose an “I provide X for Y” contract to an authorized diplomatic partner. A contract may expire or be cancelled before acceptance. The form only asks for resources: both sides exclusively use Carts and automatically mobilize the minimum number required for the load.
One Cart carries 120 resources with the active definition. The sender must already own their Carts; the recipient’s Carts are checked only when they accept. The live summary displays each convoy’s load, maximum transportable amount, remaining capacity, and required Carts; a game synchronization does not clear a form being edited.
On acceptance, the server checks both bastions’ stocks, Carts, permissions, and routes together: both linked convoys depart, or neither does. Each convoy carries exactly the accepted basket, without a diplomatic delivery modifier or delivery bonus.
Between members of the same alliance, Convoy charters only reduces travel time according to its level and never changes either basket. Carts remain their player’s property and become available again after delivery. Commercial reports remind players of both baskets and open the corresponding contract in history. History remains readable and can recreate an old offer.