What problem are you facing?

I want to be able to instruct the function to perform no lookups by providing an empty array.

How could this Function help solve your problem?

Remove the guard for non-empty slices here: https://github.com/upbound/function-msgraph/blob/main/fn.go#L1518-L1520

There are also protections here: https://github.com/upbound/function-msgraph/blob/main/fn.go#L757-L759

In summary, no listed input resulting in a successful no-op should be supported as a normal use for this function. If the input is referenced from the spec of an XRD and that referenced field needs to support an empty list, then the composition will break in the current implementation.