The Imputative Transfer is often upheld as an example of first contact gone too polite.
The gradual development of Jolibrii Worldships is well documented.
Evolved from something more similar to a plant than an animal, the Jolibrii never gained the efficiency, speed, or aggressiveness of other evolved sapient species. Instead, they formed into coalitions of unmoving life forms, with new growth and partial die-off being their primary method of change.
And the self-modifications of the Transition Protectorate is similarly well understood.
The Protectorate studied other species as best they could. According to their own records, they only attempted to blend in with locals once before realizing they were hopelessly incapable of passing as something they did not understand. But they understood plants and rocks well enough, so they were frequently and literally underfoot as they studied these species.
The initial Transition study of the stationary world ship Ponderous Vision assumed that it was an ecosystem devoid of intelligent life, and observed the gently changing environment as adapted stones until the day the Vision provided a friendly stone to sit next to the Transition ones.
This has made a lot of people very angry, but was arguably a positive move.
The Vision was forming itself to be the kind of environment it assumed the Transition agents desired…while the Transition agents were molding themselves to fit the newfound environment, each imputing preferences to the other based on evolving form. The result was a complex stream of cycles wherein each participant tried to be more accommodating for the other. This worked its way through five distinct gaseous atmospheres, upwards of twelve circadian temperature cycles all bounded by the range from -40 C to 200 C, and eighty-three calligraphic fonts that were eventually used on a new language evolved by the interplay of agent and ship.
The Transition agents utilized a subluminal communication technology modulated onto pulsar frequencies to report home. Much of the Nebula is young enough that pulsars have not developed, making Duowave Pulses safe in most circumstances.
The gradually accelerating courtesy competition could not last forever. In time the Transition agents collapsed from exhaustion at the same time that the Vision ceased growing and began focusing on rebuilding its weary interior. The ultimate result was a cordial treaty which both agents took home to their governments in exchange for permanent, less arduous assignments.