Try adding a GeometryValidator before writing data to see if there are any problematic feature that could trigger that error.

Thanks @oscard​ . I already tried but the GeometryValidator is not able to fix the issue unless there are other stuff that should be done for the geometry validator to cath those errors. See for instance this arcticle where it was recommend to use the arcSdeGridSnapper

I would use a VertexCounter followed by TestFilter to find the offending features. Polygons need atleast 3 verts, lines need atleast 2, etc.

Not the same issue, but have had similar.

FME is highly precise, often to fault. What sometimes happens, especially with spatial intersections is your input polygons, whilst visually the same, at the vertex level they are different, this could be to a fraction of a meter.

What happens is FME uses these very precise values to do the clip and often ends up with very very small polygons, or very very short lines. The output format will often have a differnet precision level and during the rounding will round some of the vertices, potentially collapsing the feature on to its self.

Using a line as an example (the same logic holds true for a polygon, a line is simplier to understand)

FME has a precision of 0.1. It creates a line that goes from 0.9 to 1.1

The output format only has a precision of 1, therefore the coordinates are rounded to 1 and 1. This isn't a valid line, so therefore throws an error