Searching for 10 200 + 30 will show the calculator widget with 2030 as result.

It appears that the widget implicitly converts a space to a multiplication, turning the calculation into 10 * 200 + 30. This is problematic because Kagi uses a space as thousands separator in the calculator widget, so using the output of the calculator results in this implicit multiplication being done.
I expect the space to be treated as a thousands separator, so that 10 200 + 30 results in 10230.