MARS: Technical Report for the CASTLE Challenge at EgoVis 2026
MARS is a multimodal system for the CASTLE 2026 challenge that reasons over 4 days of activity, 15 synchronized perspectives, transcripts, and auxiliary modalities (photos, videos, gaze, thermal imagery, heartrate). The approach uses DeepSeek for video summaries and a GPT-5.4 agent to select evidence sources. The system achieved second place on the final leaderboard.