facile

Short definition from Wiktionary

Adjective

1. 1
   Easy; contemptibly easy.
2. 2
   Amiable, flexible, easy to get along with.
3. 3
   Effortless, fluent (of work, abilities etc.).
4. 4
   Lazy, simplistic, superficial (especially of explanations, discussions etc.).
5. 5
   Of a reaction or other process, taking place readily.