As a frigate, the Massei-class is typically used within fleets as a supporting vessel. With a role dedicated to localized anti-starfighter defense and assault, it is generally spread throughout a fleet. However, the Massei-class may also be used in far smaller formations, or even independantly.
Several Massei-class have been provided to the Alien Cultures Advisory of Ish'Cong for use as escorts for diplomats sent outside Ishii space. These have been modified slightly to better permit them to fulfill their role in these cases, and to support the diplomatic purpose they then serve.
One of the first things taken into consideration when the first frigates were refit was how to permit them to better serve as a courier of diplomats. A small diplomatic shuttle was permanently assigned to each such frigate, carried on one of seven docking points that where added. In addition, a small cluster of rooms were altered and redecorated with appropriately formal decor so as to serve as possible rooms for any negotiations or formal meetings.
The rest of the seven docking points listed above can serve to dock most small craft. However, they are most often occupied by six multi-role fighters, who have their own slight alterations. Typically, they are given better sensors and communications gear, used to scout for any potential dangers rather than fight them off. This permits the frigate and the diplomatic envoy to escape quickly.
In addition to the fighters, the frigates' own complements are supplemented. Some of their anti-fighter weapons are removed, replaced with guns more capable of handling small capital ships, such as other frigates. While their primary mandate is to avoid fighting, in the case that this should prove impossible, it was agreed upon that a greater degree of autonomous power should be provided, as these escorts may be far from any friendly or Ishii forces.
Occasionally, the larger scouting parties sent to patrol the outskirts of Ishii space are not suited to a give task. When a smaller, sublter party is preferred, a recon Massei might be used. Though uncommon, such frigates do have some alterations to their designs to suit that role. The primary change is a more elaborate and expansive sensor suite, geared to locating even hidden enemies at greater ranges than a typical Massei could.