For a sub, the scope comes from several places. The spec section, the drawings, Division 01 and the general contractor's bid instructions all add to it.
A painter's scope may look like the painting section only. But the drawings may also show exposed ceilings and steel stairs to paint.
Read the spec section and every related section it names. Then read the drawings for your work. Write the scope down in your own words before you price.
Where the documents conflict, send an RFI or state your assumption. Do not guess in silence.