I created a custom assistant to use my new custom lens that limits searches to a certain set of sites. However, when using this assistant, the sources indicate that its search has returned sites from outside of that lens:

(none of the sites in the sources above are in my lens)
I assume this is a bug? I think the Assistant should use the lens to search and only get results from certain sites.
(to be clear, when using the lens in Search, everything works as expected)