in the struct Retry.Multiplier which is a floatstr.Float32OrString, there's no way to distinguish this field as not defined. In the spec, this is supposed to be an optional field. The default struct of Float32OrString will be Type Float and the zero value of FloatVal will be a 0.0 - which will be value if the workflow json/yaml left this out.

Unless i take Multiplier of 0 to be "not defined"? in which case, the specs need to be updated to say zero value is not allowed or treated as not defined