Before Combat Begins
In narrative starship combat, as with standard starship combat, each PC should know which role they’re performing before combat begins (starship roles can be found in the Core Rulebook and Character Operations Manual). In addition, the GM describes the foes (though they need not go into specifics about the stat blocks) and area in which the combat takes place to the players. The GM should also inform the players of any special rules or victory or loss conditions added to this particular combat.
Source
Starfinder Enhanced pg. 177