Two adjectives that describe the Adams-Onis Treaty are:
Controversial: The Adams-Onis Treaty was a controversial agreement between the United States and Spain, which involved the transfer of Florida to the United States and the establishment of a boundary line between the United States and Spanish territories in the Americas. The treaty was controversial because it involved the cession of territory by Spain and the displacement of indigenous people, which raised ethical and moral concerns.
Definitive: The Adams-Onis Treaty was a definitive agreement that helped to settle longstanding territorial disputes between the United States and Spain. The treaty established a clear boundary line between the two nations, which helped to reduce tensions and prevent future conflicts. The treaty also set a precedent for peaceful negotiations and diplomacy between the United States and other nations in the Americas.