This article examines the practice of the ambassadors sent by the Italian states to the court of Pope Paul II (1464-1471), focusing in particular on how they have embraced their role as an informant. Since Paul was a pope unstable, often impenetrable and inaccessible, the ambassadors were often obliged to obtain information about the Pope and his intentions indirectly. Relying heavily on the Roman diplomatic correspondence during the pontificate of Paul, this article shows how ambassadors have built networks of contacts within the papal court to ensure a continuous supply of useful information and in time. These networks thus comprised of members of any community evolving around the papacy, including well-placed cardinal, church officials, other ambassadors, political agents, as well as several informants of lower hierarchies. Rome was, indeed, an information market, so that the ambassadors had to use all their skills to take possession of the best information and most valuable.