This value reports which of the four scan modes, full, incremental, tail, or ptail, the agent is using to scan this file. An admin uses this to understand how the agent is reading the file, for example whether it re-scans the whole file each time (full) or only reads newly appended lines (tail), which affects how quickly new content is reflected in the scan results. A file being watched in tail mode is being monitored the way a live-updating log would typically be followed.