The brain is slowly coming up to speed.
Not certain what the cat sized acid lurgee critter would be useful for, but pretty much the natural animals on this planet have had a rough go at it for several millenia before the arrival of man.
And obviously so consideing the dominant creature is a large fire breathing and spitting lizard that has a hierarchy and honor system.
In my vision, the Dragon planet is one of difficult overland movement, many isolated regions giving rise to microclimates and diverse creatures.
The Dragons claimed all the best locations, feuding for hundreds of years over them. Many less desirable locations offered shelter to juveniles who could only plot and scheme, and attempt to grow more powerful.
Their economy depended on agriculture, and trade consisted of new varieties of grains, new mechanical contrivances, and decorative baubles and trinkets.
The Dragons would have their own versions of stealth assassins, and their own methods of fighting hand-to-hand, (as it were).
The Human entry was through trade and service. They tended fields and gathered in crops. They fashioned trinkets and new inventions. They built ornamentation on to the Dragon Castles and fortifications.
And the slow and venal among them plotted as the juvenile dragons did, planning and hoping for the day when it could all be theirs.
Into this chaotic social scene strode the (retired) starman Talon Starp, destroyer of ships, traveler from beyond the stars, and ... teacher.