Layer Reference Sets Overview A reference set is a named group of files plus a training category. Trained, it produces a LoRA that later runs apply by id, turning an art direction into a parameter instead of a prompt-engineering exercise every time. The mechanics (upload, , , , , , and the four categories) are covered by Layer's published skill, over both REST and MCP. This skill covers the decisions that determine whether the trained result is any good. If a sibling skill named here is missing from your available skills, ask the user to install it ( ); unattended, proceed from tool schemas a…