At the end of the First Interstellar War, the United Vitam State was not satisfied with the results of the war not being in their favor, namely the extinction of the Lykans. The Novus Initium Republic's initiative to reform the former Royal Lykan Kingdom into what would later be the Holy Lykan Republic felt like a betrayal to the State's Executive Council to the point that the State no longer considered the Humans trustworthy allies. The same was felt towards the Camino Star Empire whose objectives were met at the war's conclusion. This made the conflict from the State's point-of-view simmer down into a "cold war" to drive development of new ways to combat the Lykans. However, the introduction of the planetary shield generators by the Novus Initium Republic on Lykan (and later Liberigi Mandate) planets made planning future military strategies difficult as their weapons could not penetrate the shields.

One problem the State had to address during the cold war was the realization of the number of ships they had remaining after decades of conflict with the Lykans. The ships could be replaced but the State was quick to evaluate whether a cheaper and smaller vessel was the route to go as such ships could be built and crewed far more quickly than a destroyer or larger. The development team worked for a couple of months to design a ship, but they were also quick to point out some of the sacrifices made in their new design. The new design could not be deployed for extended journeys like larger ships as much of the cargo capacity was used towards the ammo for the weapons on board, leaving up to a week's worth of supplies for the crew. Also, armor was heavily sacrificed to reduce the mass of the vessel and make room for ammo, reactors, shield generators, engineering, and crew space. The crew space alone was highly spartan in nature, more so than other ships. Even the commanding officer had to share the same accommodations with some of his bridge crew. The ship's only defense is a single shield system with the shield boosters in place.

The resulting vessel, however, was a fast and highly maneuverable vessel that was potentially dangerous in large groups. The ship was equipped with two dual railguns for long-range engagements, two missile launchers for precision strikes, and five blasters for close-range engagements where it is the most dangerous. Between of the speed and the small size, ships from other nations would find it difficult to engage the small vessels without slowing it down or using missile launchers themselves as anti-destroyer guns would have a difficult time tracking them except at long range or  increase their tracking capabilities. It has been shown that several of these ships could be built in a very short time-frame compared to destroyers allowing hundreds to be made within a couple of months.

The Executive Council was quick to approve of the design, deeming the drawbacks as "acceptable," and ordered their production to take priority. The type of ship was simply known as a "Fast Attacker Vessel" and was not given a name by the Council. The name "Harpy" as well as the vessel being labeled as a "frigate" were both terms coined by Supreme Chancellor Drew of the Novus Initium Republic to identify the vessels. The name has been accepted by all of the nations except the State where the Executive Council does not feel the vessel name and class deserve to be named by a "traitorous" Human. However, after the Yintaka Conflict, the Representatives Parliament that ran the State until new Councilors could be selected chose to keep the name and class of vessel as the other nations would start to develop their own frigates.