"EnableMeshApiQol is not enabled" when using EditableMesh:SetVertexFaceColor()

I’m using different methods of coloring vertices / faces to figure out how they work, and it seems that:

mesh:SetVertexFaceColor(vert1, tri1, colorid1) -- vert, tri, and colorid are arbitrary

continues to throw:

Tried finding anything on this in the dev forum but requiring “EditableMeshApiQol” in google returns an xml dump from a random forum page.

Also I’m currently in the process of learning how to use editable meshes, so I may be using this method completely wrong. (The documentation for EditableMeshes is illegible)