Agastya commands security at Stratum and pilots the facility's rapid-response craft, known internally as the Doves. When Stratum's defenses are tested for real, it's Agastya's read of the threat — not a committee's — that the facility acts on.
Agastya's role puts them at the center of the mission's most kinetic sequences, and at the sharpest edge of what Stratum is willing to risk to protect what it's guarding.