Maintaining geometric accuracy when converting imported drawings into editable 2D geometry

[indiancad]

I was considering a situation where a mechanical component is imported from another CAD platform as a collection of curves and splines rather than clean lines, arcs, and polylines.

The geometry may look correct, but small deviations can cause problems when creating toolpaths, measuring profiles, or preparing manufacturing drawings. Converting everything into polylines with a fixed tolerance can also distort critical curves.

How do you decide the right curve-fitting tolerance when converting imported geometry? Do you preserve the original splines, approximate them with arcs, or use another approach to maintain manufacturing accuracy?