The IWP faculty line places Halper at Cambridge from 2001: the Centre of International Studies, later POLIS; Director of American Studies; Magdalene College life fellow from 2011. Those are academic titles on a public bio. They are how he had a room in Cambridge when Carter Page later described a July 2016 meeting there.
The Cambridge title does not, by itself, prove an FBI assignment. The Horowitz review said the Bureau did not use a confidential human source in Crossfire Hurricane before 31 July 2016. Treat the July dinner as a meeting that Page and later news reports described. Treat FBI tasking as a later, labeled episode.
No qualifying free-license photograph of Halper was located. None was generated. Prefer the bio over a stock portrait.