Rock Eater
The Rock Eater formula perfected by the Lifebringers and used in terraforming looks a lot like sourdough starter. There is a gel or liquid medium that sustains the microbes during transit. The microbe mixture is stored in tanks. The microbes convert the nutrients in the medium to oxygen, just like they do during the actual process of terraforming. This oxygen has to be removed as soon as possible to avoid killing the anaerobic microbes used in the early phases of the terraforming process. Prior to the invention of force projectors, the oxygen was used as extra reaction mass in the delivery vehicle. Afterward it is vented into space.
When it comes time to deliver the payload, there are a number of strategies used throughout history and depending on the local conditions. Sometimes, the mixture used has a low enough viscosity to be sprayed as an aerosol. The delivery vehicle enters the atmosphere and, upon getting close to the ground, sprays the rock eater in long streaks on the ground below.
Another method uses a more viscous mixture. This mixture is stored in tanks until the vehicle enters low orbit around the body to be terraformed. The vehicle injects small amounts of the mixture into what are basically paint balls, and fires the balls at the ground as it orbits.
Whatever the dispersal method used, the goal is to cover as wide an area as possible. Without pre-existing life on the planet, the microbes spread virulently, nomming the lifeless rock and turning it into breathable air.