Metallicity

Whether a material conducts. It is not written into an input file directly — it changes both how dense the mesh must be and whether smearing applies.

Quantity	What it is	Model
is_metal	True when the DFT band gap is zero	CGCNN
band_gap	The gap itself, in eV	none

There are two published CGCNNs here and only one answers a question:

	What you get	Servable?
is_metal/cgcnn	metal or insulator	yes
representation/cgcnn	64 numbers describing a crystal	no

They were fitted on different data for different purposes, so their numbers do not belong side by side.